Chapter 14: Monteggia Fracture-Dislocation in Children

Apurva S. Shah, Peter M. Waters

Chapter Outline

Introduction to Monteggia Fracture-Dislocations

Monteggia fracture-dislocations are a rare but complex injury usually involving a fracture of the ulna associated with proximal radioulnar joint dissociation and radiocapitellar dislocation. These injuries comprise less than 1% of all pediatric forearm fractures and typically affect patients between 4 and 10 years of age.77,156 The annual incidence of Monteggia fracture-dislocations in children is less than 1 in 100,000.77 In 1814, Giovanni Battista Monteggia, a surgical pathologist and public health official in Milan, Italy, first described a variation of the injury that now bears his name as “a traumatic lesion distinguished by a fracture of the proximal third of the ulna and an anterior dislocation of the proximal epiphysis of the radius.”91,107,114 In 1967, Jose Luis Bado,8,10 while director of the Orthopedic and Traumatology Institute in Montevideo, Uruguay, published his classic monograph on the classification of Monteggia lesions. Bado8,10 described a Monteggia lesion as a radial head fracture or dislocation in association with a fracture of the middle or proximal ulna. Over the last century, numerous authors have made significant contributions on pathoanatomy, classification, diagnosis, treatment, and complications.7,21,3234,37,38,48,52,55,65,70,81,83,88,89,99,106,116,119,127,131,160 
Despite the increased understanding of Monteggia lesions, the injury continues to represent a challenge for the orthopedic surgeon. In 1943, Sir Watson-Jones wrote that “no fracture presents so many problems; no injury is beset with greater difficulty; no treatment characterized by more general failure.”158 Unfortunately, despite the increased awareness and understanding of Monteggia lesions, the initial diagnosis is still missed by qualified radiologists, emergency room physicians, and orthopedic surgeons amongst others.18,42,43,48,50,60,81,84,108,119,121,127,131,151,160,163 In addition, less than optimal treatment of recognized but unstable injuries has also resulted in chronic Monteggia lesions.34,38,48,57,62,70,74,116,118,119,161 A chronic Monteggia lesion can result in substantial morbidity, and is far more complex in terms of surgical decision making and management than an acute injury.18,29,33,43,50,60,66,84,121,125 

Assessment of Monteggia Fracture-Dislocations

Classification of Monteggia Fracture-Dislocations

Bado Classification

Bado's8,10 original classification has stood the test of time with minimal modifications except for the addition of various equivalent lesions (Fig. 14-1). The classification system is based upon the direction of the radial head dislocation and the apex of the associated ulna fracture. Bado's8,10 four true Monteggia types are as follows: 
Figure 14-1
Bado classification.
 
A: Type I (anterior dislocation): The radial head is dislocated anteriorly and the ulna has a short oblique or greenstick fracture in the diaphyseal or proximal metaphyseal area. B: Type II (posterior dislocation): The radial head is posteriorly or posterolaterally dislocated; the ulna is usually fractured in the metaphysis in children. C: Type III (lateral dislocation): There is lateral dislocation of the radial head with a greenstick metaphyseal fracture of the ulna. D: Type IV (anterior dislocation with radial shaft fracture): The pattern of injury is the same as with a type I injury, with the inclusion of a radial shaft fracture distal to the level of the ulnar fracture.
A: Type I (anterior dislocation): The radial head is dislocated anteriorly and the ulna has a short oblique or greenstick fracture in the diaphyseal or proximal metaphyseal area. B: Type II (posterior dislocation): The radial head is posteriorly or posterolaterally dislocated; the ulna is usually fractured in the metaphysis in children. C: Type III (lateral dislocation): There is lateral dislocation of the radial head with a greenstick metaphyseal fracture of the ulna. D: Type IV (anterior dislocation with radial shaft fracture): The pattern of injury is the same as with a type I injury, with the inclusion of a radial shaft fracture distal to the level of the ulnar fracture.
View Original | Slide (.ppt)
Figure 14-1
Bado classification.
A: Type I (anterior dislocation): The radial head is dislocated anteriorly and the ulna has a short oblique or greenstick fracture in the diaphyseal or proximal metaphyseal area. B: Type II (posterior dislocation): The radial head is posteriorly or posterolaterally dislocated; the ulna is usually fractured in the metaphysis in children. C: Type III (lateral dislocation): There is lateral dislocation of the radial head with a greenstick metaphyseal fracture of the ulna. D: Type IV (anterior dislocation with radial shaft fracture): The pattern of injury is the same as with a type I injury, with the inclusion of a radial shaft fracture distal to the level of the ulnar fracture.
A: Type I (anterior dislocation): The radial head is dislocated anteriorly and the ulna has a short oblique or greenstick fracture in the diaphyseal or proximal metaphyseal area. B: Type II (posterior dislocation): The radial head is posteriorly or posterolaterally dislocated; the ulna is usually fractured in the metaphysis in children. C: Type III (lateral dislocation): There is lateral dislocation of the radial head with a greenstick metaphyseal fracture of the ulna. D: Type IV (anterior dislocation with radial shaft fracture): The pattern of injury is the same as with a type I injury, with the inclusion of a radial shaft fracture distal to the level of the ulnar fracture.
View Original | Slide (.ppt)
X

Bado Type I

A Bado type I lesion is an anterior dislocation of the radial head associated with an apex anterior ulnar diaphyseal fracture at any level. This is the most common Monteggia lesion in children and represents approximately 70% to 75% of all injuries.38,53,81,119,156 

Bado Type II

A Bado type II lesion is a posterior or posterolateral dislocation of the radial head associated with an apex posterior ulnar diaphyseal or metaphyseal fracture. This pattern is the most common Monteggia lesion in adults, but is relatively rare in children.105,106,119 Type II lesions account for 6% of Monteggia lesions in children,77 and are usually found in older patients105 who have sustained significant trauma.41,116,117 

Bado Type III

A Bado type III lesion is a lateral dislocation of the radial head associated with a varus (apex lateral) fracture of the proximal ulna. This is the second most common pediatric Monteggia lesion.13,48,98,103,160 When an injury is characterized by an olecranon fracture and a lateral or anterolateral radiocapitellar dislocation but no radioulnar dissociation, the injury is not a true Monteggia lesion.63,118,146 

Bado Type IV

A Bado type IV lesion is an anterior dislocation of the radial head associated with fractures of both the ulna and the radius. The original description was of a radial fracture at the same level or distal to the ulna fracture. Type IV lesions are relatively rare in children. 

Expansion of the Bado Classification: Monteggia Equivalent Lesions

Bado8,10 classified certain injuries as equivalents to true Monteggia lesions because of their similar mechanisms of injury, radiographic appearance, or treatment methods. Since his original publication, the list of equivalent lesions has expanded case report by case report. 

Type I Equivalents

Bado type I equivalents (Fig. 14-2) include isolated anterior dislocations of the radial head without ulnar fracture. This subclassification includes a “pulled elbow” or “nursemaid's elbow” because the mechanism of longitudinal traction, pronation, and hyperextension is similar to a true type I lesion. In nursemaid's elbow cases, the radiographs are normal. In type I equivalent lesions, the radial head is malaligned in its relationship to the capitellum and proximal ulna. However, the ulnar bow sign (Fig. 14-3) is normal as opposed to subtle plastic deformation of the ulna which will have a concave ulnar bow and can be misdiagnosed as a type I equivalent when the injury is really a Bado I lesion. This distinction can be critical in terms of operative decision making in that the type I equivalent lesion requires only open repair of the displaced ligament while the Bado type I lesion with plastic deformation requires correction of the ulnar deformity. Other type I equivalents (Fig. 14-2) include anterior dislocation of the radial head with ulnar metaphyseal or diaphyseal fracture and radial neck fracture; anterior dislocation of the radial head with radial diaphyseal fracture more proximal to ulnar diaphyseal fracture; anterior radial head dislocation with ulnotrochlear dislocation (Fig. 14-4)119; and anterior dislocation of the radial head with segmental ulna fracture.2,53,63,110,123,146 More case reports will probably expand this subclassification over time. The type I equivalents have been shown to have poorer outcomes and require more frequent operative intervention than true Monteggia lesions.53,98 Poor outcomes may relate to intra-articular injury, coronoid fracture, comminution of the ulna fracture, and comminution of the radial head fracture.126 
Figure 14-2
Type I equivalents.
 
A: Isolated anterior radial head dislocation. B: Ulnar fracture with fracture of the radial neck. C: Isolated radial neck fractures. D: Elbow (ulnohumeral) dislocation with or without fracture of the proximal radius.
A: Isolated anterior radial head dislocation. B: Ulnar fracture with fracture of the radial neck. C: Isolated radial neck fractures. D: Elbow (ulnohumeral) dislocation with or without fracture of the proximal radius.
View Original | Slide (.ppt)
Figure 14-2
Type I equivalents.
A: Isolated anterior radial head dislocation. B: Ulnar fracture with fracture of the radial neck. C: Isolated radial neck fractures. D: Elbow (ulnohumeral) dislocation with or without fracture of the proximal radius.
A: Isolated anterior radial head dislocation. B: Ulnar fracture with fracture of the radial neck. C: Isolated radial neck fractures. D: Elbow (ulnohumeral) dislocation with or without fracture of the proximal radius.
View Original | Slide (.ppt)
X
Figure 14-3
The ulnar bow line.
 
This line, drawn between the distal ulna and the olecranon, defines the ulnar bow. The ulnar bow sign is deviation of the ulnar border from the reference line by more than 1 mm.
This line, drawn between the distal ulna and the olecranon, defines the ulnar bow. The ulnar bow sign is deviation of the ulnar border from the reference line by more than 1 mm.
View Original | Slide (.ppt)
Figure 14-3
The ulnar bow line.
This line, drawn between the distal ulna and the olecranon, defines the ulnar bow. The ulnar bow sign is deviation of the ulnar border from the reference line by more than 1 mm.
This line, drawn between the distal ulna and the olecranon, defines the ulnar bow. The ulnar bow sign is deviation of the ulnar border from the reference line by more than 1 mm.
View Original | Slide (.ppt)
X
Figure 14-4
Type I equivalent that includes elbow subluxation in addition to the radioulnar dislocation.
Flynn-ch014-image004.png
View Original | Slide (.ppt)
X

Type II Equivalents

Bado8,10 described type II equivalents to include posterior radial head dislocations associated with fractures of the proximal radial epiphysis or radial neck. 

Type III and Type IV Equivalents

Bado8,10 did not have equivalent lesions for the true type III and type IV lesions. Because mechanism of injury allows for this subclassification, case reports have emerged over time to include fractures of the distal humerus (supracondylar, lateral condylar) in association with proximal forearm fractures (Fig. 14-5).5,16,17,36,46,51,53,54,86,95,110,115,120,123,129 
Figure 14-5
Type III equivalent described by Ravessoud115: An oblique fracture of the ulna with varus alignment and a displaced lateral condylar fracture.
 
Type IV equivalent described by Arazi5: Fractures of the distal humerus, ulnar diaphysis, and radial neck.
Type IV equivalent described by Arazi5: Fractures of the distal humerus, ulnar diaphysis, and radial neck.
View Original | Slide (.ppt)
Figure 14-5
Type III equivalent described by Ravessoud115: An oblique fracture of the ulna with varus alignment and a displaced lateral condylar fracture.
Type IV equivalent described by Arazi5: Fractures of the distal humerus, ulnar diaphysis, and radial neck.
Type IV equivalent described by Arazi5: Fractures of the distal humerus, ulnar diaphysis, and radial neck.
View Original | Slide (.ppt)
X

Letts Classification

Letts et al.81 have described an alternate classification schedule for pediatric Monteggia fracture-dislocations based both on direction of radial head dislocation and the type of ulnar fracture (Fig. 14-6). Letts types A, B, and C are analogous to Bado type I lesions and are characterized by anterior dislocation of the radial head with an associated ulnar fracture. In a type A lesion there is plastic deformation of the ulna; in a type B lesion there is an incomplete or greenstick ulnar fracture, and in a type C lesion there is a complete ulnar fracture. Letts type D lesions are equivalent to Bado type II injuries and are characterized by posterior radial head dislocation. Letts type E lesions are equivalent to Bado type III injuries and are characterized by lateral radial head dislocation. 
Figure 14-6
Pediatric Monteggia fracture-dislocation classification by Letts et al.81
 
A: Anterior dislocation of the radial head with plastic deformation of the ulna. B: Anterior dislocation of the radial head with greenstick fracture of the ulna. C: Anterior dislocation of the radial head with complete fracture of the ulna. D: Posterior dislocation of the radial head with fracture of the ulnar metaphysis. E: Lateral dislocation of the radial head and metaphyseal greenstick fracture of the ulna.
A: Anterior dislocation of the radial head with plastic deformation of the ulna. B: Anterior dislocation of the radial head with greenstick fracture of the ulna. C: Anterior dislocation of the radial head with complete fracture of the ulna. D: Posterior dislocation of the radial head with fracture of the ulnar metaphysis. E: Lateral dislocation of the radial head and metaphyseal greenstick fracture of the ulna.
View Original | Slide (.ppt)
Figure 14-6
Pediatric Monteggia fracture-dislocation classification by Letts et al.81
A: Anterior dislocation of the radial head with plastic deformation of the ulna. B: Anterior dislocation of the radial head with greenstick fracture of the ulna. C: Anterior dislocation of the radial head with complete fracture of the ulna. D: Posterior dislocation of the radial head with fracture of the ulnar metaphysis. E: Lateral dislocation of the radial head and metaphyseal greenstick fracture of the ulna.
A: Anterior dislocation of the radial head with plastic deformation of the ulna. B: Anterior dislocation of the radial head with greenstick fracture of the ulna. C: Anterior dislocation of the radial head with complete fracture of the ulna. D: Posterior dislocation of the radial head with fracture of the ulnar metaphysis. E: Lateral dislocation of the radial head and metaphyseal greenstick fracture of the ulna.
View Original | Slide (.ppt)
X

Author's Preferred Classification

Ring, Jupiter, and Waters118,119 defined a Monteggia lesion as a proximal radioulnar joint dislocation in association with a forearm fracture. In this classification system, it is the character of the ulnar fracture, more so than the direction of the radial head dislocation, that is most useful in determining the optimal treatment of Monteggia fracture-dislocations in both adults and children. Stable anatomic reduction of the ulnar fracture almost always results in anatomic, stable reduction of the radial head, proximal radioulnar joint, and radiocapitellar joint in the acute setting. The ulnar fracture is defined similarly to all pediatric forearm fractures: Plastic deformation, incomplete or greenstick fractures, and complete fractures. Complete fractures are further subdivided into transverse, short oblique, long oblique, and comminuted fractures. Treatment directly relates to the fracture type: Closed reduction for plastic deformation and greenstick fractures; intramedullary fixation for transverse and short oblique fractures; and open reduction and internal fixation with plate and screws for long oblique and comminuted fractures (Table 14-1). 
 
Table 14-1
Author's Classification of Monteggia Fracture-dislocations
Type Dislocation Fracture
True lesions
I Anterior Metaphysis–diaphysis
II Posterior Metaphysis–diaphysis
III Lateral Metaphysis
IV Anterior Radial diaphysis, ulnar diaphysis
Hybrid lesion Anterior, posterior, or lateral Metaphysis or olecranon
Type Description
Equivalent lesions
I Isolated dislocation of radial head
Radial neck fracture (isolated)
Radial neck fracture in combination with a fracture of the ulnar diaphysis
Radial and ulnar fractures with the radial fracture above the junction of the middle and proximal thirds
Fracture of ulnar diaphysis with anterior dislocation of radial head and an olecranon fracture
II Posterior dislocation of the elbow
III Ulnar fracture with displaced fracture of the lateral condyle
IV None described
X

Mechanisms of Injury for Monteggia-Fracture Dislocations

Type I Mechanism of Injury

Three separate mechanisms of type I lesions have been described: direct trauma,10,22,27,42,96,113,116,131,151 hyperpronation, and hyperextension.22,116 

Direct Blow Theory

The first theory proposed in English literature was the direct blow mechanism described by Speed and Boyd131 and endorsed by Smith (Fig. 14-7).127 This theory was actually proposed by Monteggia,91 who noted that the fracture occurs when a direct blow on the posterior aspect of the forearm first produces a fracture through the ulna. Then, either by continued deformation or direct pressure, the radial head is forced anteriorly with respect to the capitellum, causing the radial head to dislocate. Monteggia91 explained that these injuries sometimes resulted from a blow by a staff or cudgel on the forearm raised to protect the head. 
Figure 14-7
Mechanism of injury for type I Monteggia lesions: Direct blow theory.
 
The fracture-dislocation is sustained by direct contact on the posterior aspect of the forearm, either by falling onto an object or by an object striking the forearm. The continued motion of the object forward dislocates the radial head after fracturing the ulna.
The fracture-dislocation is sustained by direct contact on the posterior aspect of the forearm, either by falling onto an object or by an object striking the forearm. The continued motion of the object forward dislocates the radial head after fracturing the ulna.
View Original | Slide (.ppt)
Figure 14-7
Mechanism of injury for type I Monteggia lesions: Direct blow theory.
The fracture-dislocation is sustained by direct contact on the posterior aspect of the forearm, either by falling onto an object or by an object striking the forearm. The continued motion of the object forward dislocates the radial head after fracturing the ulna.
The fracture-dislocation is sustained by direct contact on the posterior aspect of the forearm, either by falling onto an object or by an object striking the forearm. The continued motion of the object forward dislocates the radial head after fracturing the ulna.
View Original | Slide (.ppt)
X
The parry fracture, another term for the Monteggia fracture-dislocation, has been mentioned in the literature. During the American Civil War, Monteggia fractures were frequent because of direct blows on the forearm received while attempting to parry the butt of a rifle during hand-to-hand combat. The major argument against this theory as the mechanism is that in the usual clinical situation, there rarely is evidence of a direct blow to the posterior aspect of the forearm, such as a contusion or laceration.42,151 

Hyperpronation Theory

In 1949, Evans42 published his observations regarding anterior Monteggia fracture-dislocations. Previous investigators had based their direct blow theory on hypothesis and clinical observation, but Evans used cadaveric investigation to support his hyperpronation theory. He demonstrated that hyperpronation of the forearm produced a fracture of the ulna with a subsequent dislocation of the radial head. He postulated that during a fall, the outstretched hand, initially in pronation, is forced into further pronation as the body twists above the planted hand and forearm (Fig. 14-8). This hyperpronation forcibly rotates the radius over the middle of the ulna, resulting in either anterior dislocation of the radial head or fracture of the proximal third of the radius, along with fracture of the ulna. In actual patients reported on by Evans, the ulnar fractures demonstrated a pattern consistent with anterior tension and shear or longitudinal compression. His cadaveric investigation, however, showed the ulnar fracture pattern to be consistent with a spiral or rotational force. The hyperpronation theory was also supported by Bado.9 
Figure 14-8
Mechanism of injury for type I Monteggia lesions: Hyperpronation theory (Evans).42
 
Rotation of the body externally forces the forearm into pronation. The ulnar shaft fractures with further rotation, forcibly dislocating the radial head.
Rotation of the body externally forces the forearm into pronation. The ulnar shaft fractures with further rotation, forcibly dislocating the radial head.
View Original | Slide (.ppt)
Figure 14-8
Mechanism of injury for type I Monteggia lesions: Hyperpronation theory (Evans).42
Rotation of the body externally forces the forearm into pronation. The ulnar shaft fractures with further rotation, forcibly dislocating the radial head.
Rotation of the body externally forces the forearm into pronation. The ulnar shaft fractures with further rotation, forcibly dislocating the radial head.
View Original | Slide (.ppt)
X
Two arguments have been used to dispute the hyperpronation mechanism.151 First, the ulnar fracture rarely presents clinically in a spiral pattern; it is often oblique, indicating an initial force in tension with propagation in shear rather than rotational. Second, the Evans experiments, which were performed on totally dissected forearms,42 did not take into consideration the dynamic muscle forces at play during a fall on an outstretched hand. 

Hyperextension Theory

In 1971, Tompkins151 analyzed both theories and presented good clinical evidence that type I Monteggia fracture-dislocations were caused by a combination of dynamic and static forces. His study postulated three steps in the fracture mechanism: Hyperextension, radial head dislocation, and ulnar fracture (Fig. 14-9). The patient falls on an outstretched arm with forward momentum, forcing the elbow joint into hyperextension. The radius is first dislocated anteriorly by the violent reflexive contracture of the biceps, forcing the radius away from the capitellum. Once the proximal radius dislocates, the weight of the body is transferred to the ulna. Because the radius is usually the main load-bearing bone in the forearm, the ulna cannot handle the transmitted longitudinal force and, subsequently, fails in tension. This tension force produces an oblique fracture line or a greenstick fracture in the ulnar diaphysis or at the diaphyseal–metaphyseal junction. In addition to the momentum of the injury, the anterior angulation of the ulna results from the pull of the intact interosseous membrane on the distal fragment, causing it to follow the radius. The brachialis muscle causes the proximal ulnar fragment to flex. 
Figure 14-9
Mechanism of injury for type I Monteggia lesions: Hyperextension theory (Tompkins).151
 
A: Forward momentum caused by a fall on an outstretched hand forces the elbow into hyperextension. B: The biceps contracts, forcibly dislocating the radial head. C: Continued forward momentum causes the ulna to fracture because of tension on the anterior surface.
A: Forward momentum caused by a fall on an outstretched hand forces the elbow into hyperextension. B: The biceps contracts, forcibly dislocating the radial head. C: Continued forward momentum causes the ulna to fracture because of tension on the anterior surface.
View Original | Slide (.ppt)
Figure 14-9
Mechanism of injury for type I Monteggia lesions: Hyperextension theory (Tompkins).151
A: Forward momentum caused by a fall on an outstretched hand forces the elbow into hyperextension. B: The biceps contracts, forcibly dislocating the radial head. C: Continued forward momentum causes the ulna to fracture because of tension on the anterior surface.
A: Forward momentum caused by a fall on an outstretched hand forces the elbow into hyperextension. B: The biceps contracts, forcibly dislocating the radial head. C: Continued forward momentum causes the ulna to fracture because of tension on the anterior surface.
View Original | Slide (.ppt)
X

Summary of Type I Mechanism of Injury

The type I lesion can probably be caused by any of the three proposed mechanisms, but the most common mechanism is a fall on an outstretched hand that forces the elbow into complete extension, locking the olecranon into the humerus. The forearm is in a rotational position of neutral to midpronation. As the proximal ulna locks into the distal humerus, the bending force stresses the proximal radioulnar joint. Because of the relatively pronated position of the joint, the ligamentous restraints are lax, providing only tenuous stability for the radial head. The anterior bending force, combined with a reflexive contraction of the biceps, violently dislocates the radial head anteriorly. The radioulnar joint and its ligamentous complex are at risk because of the ligamentous laxity and the decreased contact area between the proximal radius and ulna created by the rotation of the forearm. At midrotation, the short axis of the elliptical radial head is perpendicular to the ulna, causing the annular ligament and the dense anterior portion of the quadrate ligament to be relaxed. The contact area of the proximal radioulnar joint, because of the shape of the radial head, is also decreased, further reducing the stability of the joint. The ulna, now the main weight-bearing structure of the forearm, is loaded by a continued bending moment, causing tension on the anterior cortex and producing failure. The force at the site of failure is propagated in shear at approximately 45 degrees to the long axis of the ulna. This mechanism may produce plastic deformation with an anterior bow, a greenstick fracture, or an oblique fracture pattern, all of which are observed clinically. As the anterior bending movement continues, the vector of the biceps changes and acts as a tether and resists any further advance of the proximal radius. The distal fragment of the ulna continues to advance, acting as a fulcrum against the radial shaft. The anteriorly directed force of the distal ulnar fragment, combined with the retrograde resistance of the biceps, may create a fracture of the radius, or a type IV lesion. 

Type II Mechanism of Injury for Monteggia-Fracture Dislocations

The cause of the type II Monteggia lesion is subject to debate. Bado10 thought the lesion was caused by direct force and sudden supination. Penrose108 analyzed seven fractures in adults and noted that a proximal ulnar fracture was the typical pattern. He postulated that the injury occurred by longitudinal loading rather than by direct trauma.131 Olney and Menelaus98 reported four type II lesions in their series of pediatric Monteggia fractures. Three of these patients had proximal ulnar fractures and one had an oblique midshaft fracture, suggesting two different mechanisms of injury. 
The mechanism proposed and experimentally demonstrated by Penrose108 was that type II lesions occur when the forearm is suddenly loaded in a longitudinal direction with the elbow in approximately 60 degrees of flexion. This investigation demonstrated that a type II lesion occurred consistently if the ulna fractured; otherwise, a posterior elbow dislocation was produced (Fig. 14-10). The difference in bone strength of the ulna may explain the reason for the high incidence of type II Monteggia lesions in older adults and their rarity in children. Penrose108 further noted that the rotational position of the forearm did not seem to affect the type of fracture produced. 
Figure 14-10
Mechanism of injury for type II Monteggia lesions.
 
A: With the elbow flexed approximately 60 degrees; a longitudinal force is applied, parallel to the long axis of the forearm. B: This force may result in a posterior elbow dislocation. C: If the integrity of the anterior cortex of the ulna is compromised, a type II fracture-dislocation occurs.
A: With the elbow flexed approximately 60 degrees; a longitudinal force is applied, parallel to the long axis of the forearm. B: This force may result in a posterior elbow dislocation. C: If the integrity of the anterior cortex of the ulna is compromised, a type II fracture-dislocation occurs.
View Original | Slide (.ppt)
Figure 14-10
Mechanism of injury for type II Monteggia lesions.
A: With the elbow flexed approximately 60 degrees; a longitudinal force is applied, parallel to the long axis of the forearm. B: This force may result in a posterior elbow dislocation. C: If the integrity of the anterior cortex of the ulna is compromised, a type II fracture-dislocation occurs.
A: With the elbow flexed approximately 60 degrees; a longitudinal force is applied, parallel to the long axis of the forearm. B: This force may result in a posterior elbow dislocation. C: If the integrity of the anterior cortex of the ulna is compromised, a type II fracture-dislocation occurs.
View Original | Slide (.ppt)
X
Haddad et al.58 described type II injuries caused by low-velocity injuries in six adults, five of whom were on long-term corticosteroid therapy. They suggested that this supports the theory that the type II Monteggia injury is a variant of posterior elbow dislocation, in that it occurs when the ulna is weaker than the ligaments surrounding the elbow joint, resulting in an ulnar fracture before the ligament disruption required for dislocation. 

Type III Mechanism of Injury for Monteggia-Fracture Dislocations

Wright163 studied fractures of the proximal ulna with lateral and anterolateral dislocations of the radial head and concluded that the mechanism of injury was varus stress at the level of the elbow, in combination with an outstretched hand planted firmly against a fixed surface (Fig. 14-11). This usually produces a greenstick ulnar fracture with tension failure radially and compression medially. The radial head dislocates laterally, rupturing the annular ligament. Hume63 suggested that type III lesions may be the result of hyperextension of the elbow combined with pronation of the forearm. Other authors confirmed the mechanism of varus force at the elbow as the cause of type III injuries.10,38,93,106,146 The direction of the radial head dislocation is probably determined by the rotational and angular force applied simultaneously to the varus moment at the elbow.93 
Figure 14-11
Mechanism of injury for type III Monteggia lesions.
 
A forced varus stress causes a greenstick fracture of the proximal ulna and a true lateral or anterolateral radial head dislocation.
A forced varus stress causes a greenstick fracture of the proximal ulna and a true lateral or anterolateral radial head dislocation.
View Original | Slide (.ppt)
Figure 14-11
Mechanism of injury for type III Monteggia lesions.
A forced varus stress causes a greenstick fracture of the proximal ulna and a true lateral or anterolateral radial head dislocation.
A forced varus stress causes a greenstick fracture of the proximal ulna and a true lateral or anterolateral radial head dislocation.
View Original | Slide (.ppt)
X

Type IV Mechanism of Injury for Monteggia-Fracture Dislocations

Bado8 proposed that a type IV lesion is caused by hyperpronation. Of the case reports discussing the mechanism of injury, both hyperpronation48 and a direct blow120 have been postulated. Olney and Menelaus98 reported a single type IV lesion in their series but did not discuss the mechanism. Type IV lesions appear to be caused by the mechanism described for type I lesions. 

Associated Injuries with Monteggia Fracture-dislocations

Monteggia lesions have been associated with fractures of the wrist and the distal forearm,10 including distal radial and ulnar metaphyseal and diaphyseal fractures.10,64,66,120 Galeazzi fractures may also occur with Monteggia lesions.10,27,28,80 Radial head and neck fractures are commonly associated with type II fractures10,77 but may occur with other types.1,45,49,141 With a type II lesion, the radial head fracture is usually at the anterior rim.41,105 Strong et al.140 reported two type I equivalent lesions consisting of a fractured radial neck and midshaft ulnar fracture. This injury pattern is notable because of significant medial displacement of the distal radial fragment. Obtaining and maintaining reduction of the radius proved difficult with a closed technique. 
Fractures of the distal humerus lateral condyle have also been associated with Monteggia fractures.31,106 Ravessoud115 reported an ipsilateral ulnar shaft lesion and a lateral condylar fracture without loss of the radiocapitellar relation, suggesting a type II equivalent (Fig. 14-5). Kloen et al.72 reported a bilateral Monteggia fracture-dislocation and described the operative technique for its treatment. Despite surgical and rehabilitative challenges, excellent results were obtained in both elbows. In essence, any fracture about the elbow and forearm should be inspected for an associated Monteggia lesion. 

Signs and Symptoms of Monteggia Fracture-dislocations

Type I Clinical Findings

Bado,8,10 in his original description, provided an accurate clinical picture of Monteggia fracture-dislocations. In general, there is fusiform swelling about the elbow. The child has significant pain and has limitations in elbow flexion and extension as well as forearm pronation and supination. Usually, an angular change in the forearm itself is evident, with the apex shifted anteriorly and mild valgus apparent. There may be tenting of the skin or an area of ecchymosis on the volar aspect of the forearm. It is imperative to check for an open fracture wound. The child may not be able to extend the fingers at the metacarpophalangeal joints or retropulse the thumb secondary to a posterior interosseous nerve palsy. Later, as the swelling subsides, anterior fullness may remain in the cubital fossa for the typical type I lesion. However, this finding may be subtle because children will usually have an elbow flexion posture following injury. If the injury is seen late, there will be a loss of full flexion at the elbow and a palpable anterior dislocation of the radial head. The radial head–distal humerus impingement that occurs may be a source of pain with activities. There is usually loss of forearm rotation with late presentation. Progressive valgus may occur if the anterior radial head dislocation worsens. 

Type II Clinical Findings

Similar to type I lesions, the elbow region is swollen but exhibits posterior angulation of the proximal forearm and a marked prominence in the area posterolateral to the normal location of the radial head. The entire upper extremity should be examined because of the frequency of associated injuries.74,105 

Type III Clinical Findings

Lateral swelling, varus deformity of the elbow, and significant limitation of motion (especially supination) are the hallmarks of type III Monteggia fracture-dislocations. Again, these signs can be subtle and missed by harried clinicians. Injuries to the radial nerve, particularly the posterior interosseous branch, occur more frequently with type III lesions than other Monteggia fracture-dislocations.13,119,134 

Type IV Clinical Findings

The appearance of the limb with a type IV lesion is similar to that of a type I lesion. However, more swelling and pain can be present because of the magnitude of force required to create this complex injury. Particular attention should be given to the neurovascular status of the limb, anticipating the possible increased risk for a compartment syndrome. 

Clinical Findings in Monteggia Equivalents and Associated Injuries

In a Monteggia equivalent injury, clinical findings are similar to those for the corresponding Bado lesion, with the common triad of pain, swelling, and deformity. Given the frequency of associated skeletal injuries, a careful examination of the entire upper extremity should be performed. This involves careful inspection of the skin and palpation of the distal humerus lateral condyle, the distal radius, and the distal radioulnar joint. Given the high frequency of radial nerve injuries with Monteggia fracture-dislocations,13,14,63,96,119,127,134 a careful examination of neurologic examination should be performed. Because the posterior interosseous branch is most commonly injured, the clinician should routinely examine motor function of the extensor digitorum comminus and the extensor pollicis longus. Failure to extend the fingers at the metacarpophalangeal joints or retropulse the thumb are concerning for a posterior interosseous nerve palsy. 

Imaging and Other Diagnostic Studies for Monteggia-Fracture Dislocations

The standard evaluation of a Monteggia fracture-dislocation includes anteroposterior (AP) and lateral radiographs of the forearm and elbow. Any disruption of the ulna, including subtle changes in ulnar bowing, should alert the clinician to look for disruption of the proximal radioulnar joint.30,32,68,70,83 Unfortunately, the dislocated radial head is all too often missed in the acute setting. It must be stressed that every forearm and elbow injury requires close scrutiny of the radial head–capitellar relationship. In cases where plain radiographs are concerning but equivocal, fluoroscopic imaging or cross-sectional imaging such as magnetic resonance imaging (MRI) or ultrasound scan should be strongly considered. The goal for every radiologist, orthopedist, and emergency department physician should be to never miss a Monteggia lesion in the acute setting. 

Type I Radiographic Evaluation

The radiographic alignment of the radial head and capitellum is particularly important and is best defined by a true lateral view of the elbow. In a type I Monteggia fracture-dislocation, the radiocapitellar relationship may appear normal on an AP radiograph despite obvious disruption on the lateral view (Fig. 14-12). If there is any doubt regarding the radiocapitellar alignment, further radiographic evaluation must be obtained. Smith127 and later Storen138 noted that a line drawn through the center of the radial neck and head should extend directly through the center of the capitellum. This alignment should remain intact regardless of the degree of flexion or extension of the elbow (Fig. 14-13). In some instances, there is disruption of the radiocapitellar line in a normal elbow. Miles and Finlay90 pointed out that the radiocapitellar line passes through the center of the capitellum only on a true lateral projection. They reported five patients in whom the elbow was clinically normal but the radiocapitellar line appeared disrupted. In analyzing the radiographs, they found that the radiographic projection of the elbow was usually an oblique view or that the forearm was pronated in the radiograph. If this disruption appears on radiographs in a child with an acute injury, however, it is the treating surgeon's responsibility to ensure that it is an insignificant finding. 
Figure 14-12
Type I lesion.
 
A: The AP forearm radiograph demonstrates an ulnar fracture and an apparently located radial head. B: However, the lateral view reveals anterior dislocation of the radial head. Note the disruption of the radiocapitellar line.
A: The AP forearm radiograph demonstrates an ulnar fracture and an apparently located radial head. B: However, the lateral view reveals anterior dislocation of the radial head. Note the disruption of the radiocapitellar line.
View Original | Slide (.ppt)
Figure 14-12
Type I lesion.
A: The AP forearm radiograph demonstrates an ulnar fracture and an apparently located radial head. B: However, the lateral view reveals anterior dislocation of the radial head. Note the disruption of the radiocapitellar line.
A: The AP forearm radiograph demonstrates an ulnar fracture and an apparently located radial head. B: However, the lateral view reveals anterior dislocation of the radial head. Note the disruption of the radiocapitellar line.
View Original | Slide (.ppt)
X
Figure 14-13
Radiocapitellar line.
 
A composite drawing with the elbow in various degrees of flexion. A line drawn down the long axis of the radius bisects the capitellum of the humerus regardless of the degree of flexion or extension of the elbow.
A composite drawing with the elbow in various degrees of flexion. A line drawn down the long axis of the radius bisects the capitellum of the humerus regardless of the degree of flexion or extension of the elbow.
View Original | Slide (.ppt)
Figure 14-13
Radiocapitellar line.
A composite drawing with the elbow in various degrees of flexion. A line drawn down the long axis of the radius bisects the capitellum of the humerus regardless of the degree of flexion or extension of the elbow.
A composite drawing with the elbow in various degrees of flexion. A line drawn down the long axis of the radius bisects the capitellum of the humerus regardless of the degree of flexion or extension of the elbow.
View Original | Slide (.ppt)
X
As John Hall often said, “Monteggia lesions are not like throwing horse shoes; being close does not count.” It is still too frequent an occurrence that a highly qualified, distraught, orthopedic surgeon will call for referral of a chronic Monteggia lesion that was missed acutely. With late presentation of a chronic Monteggia injury, an MRI scan may be useful to determine the congruency of the radial head and capitellum. If the radial head is no longer centrally concave or the capitellum is no longer symmetrically convex, surgical reduction may fail to improve pain or restore motion. 

Type II Radiographic Evaluation

Standard AP and lateral radiographs of the forearm demonstrate the pertinent features for classifying type II Monteggia fracture-dislocations. The typical findings include a proximal metaphyseal fracture of the ulna, with possible extension into the olecranon (Fig. 14-14).41,98,147 Oblique diaphyseal ulnar fractures can also result in a type II Monteggia lesion.8,41,98 The radial head is dislocated posteriorly or posterolaterally10 and should be carefully examined for other injuries. Accompanying fractures of the anterior margin of the radial head have been noted.41,105 Initially, these rim fractures are subtle in children but can lead to progressive subluxation and make late reconstruction difficult. Cross-sectional imaging, such as an MRI or ultrasound scan, should be obtained if further characterization of the injury pattern is deemed warranted. 
Figure 14-14
Type II lesion.
 
The typical radiographic findings include A: A posterior dislocation of the radial head (arrows) and (B) A proximal metaphyseal fracture, which may extend into the olecranon (arrows). C: The radial head dislocation also may be posterolateral (arrows).
The typical radiographic findings include A: A posterior dislocation of the radial head (arrows) and (B) A proximal metaphyseal fracture, which may extend into the olecranon (arrows). C: The radial head dislocation also may be posterolateral (arrows).
View Original | Slide (.ppt)
Figure 14-14
Type II lesion.
The typical radiographic findings include A: A posterior dislocation of the radial head (arrows) and (B) A proximal metaphyseal fracture, which may extend into the olecranon (arrows). C: The radial head dislocation also may be posterolateral (arrows).
The typical radiographic findings include A: A posterior dislocation of the radial head (arrows) and (B) A proximal metaphyseal fracture, which may extend into the olecranon (arrows). C: The radial head dislocation also may be posterolateral (arrows).
View Original | Slide (.ppt)
X

Type III Radiographic Evaluation

In type III lesions, the radial head is displaced laterally or anterolaterally,104,106 which is best visualized on the AP radiograph (Fig. 14-15). The ulnar fracture often is in the metaphyseal region,10,13,63,69,92,119,163 but it can also occur more distally.10,11,47,162 Varus deformity is common to all ulna fractures, regardless of the level. Radiographs of the entire forearm should be obtained because of the association of distal radial and ulnar fractures with this complex elbow injury.147 As with all Monteggia injuries, the acute lesion can be missed if proper radiographs are not obtained and careful evaluation of the studies is not performed. 
Figure 14-15
Type III lesion.
 
A: AP radiographs of the bilateral forearms demonstrate residual bow of the proximal ulna after an incompletely reduced type III lesion (persistent varus deformity). B: The persistent bow resulted in symptomatic lateral subluxation of the radial head.
A: AP radiographs of the bilateral forearms demonstrate residual bow of the proximal ulna after an incompletely reduced type III lesion (persistent varus deformity). B: The persistent bow resulted in symptomatic lateral subluxation of the radial head.
View Original | Slide (.ppt)
Figure 14-15
Type III lesion.
A: AP radiographs of the bilateral forearms demonstrate residual bow of the proximal ulna after an incompletely reduced type III lesion (persistent varus deformity). B: The persistent bow resulted in symptomatic lateral subluxation of the radial head.
A: AP radiographs of the bilateral forearms demonstrate residual bow of the proximal ulna after an incompletely reduced type III lesion (persistent varus deformity). B: The persistent bow resulted in symptomatic lateral subluxation of the radial head.
View Original | Slide (.ppt)
X

Type IV Radiographic Evaluation

In a type IV Monteggia fracture-dislocation, the anterior radial head dislocation is similar to that in a type I lesion (Fig. 14-16). The radial and ulnar fractures generally are in the middle third of the shaft,39 with the radial fracture typically distal to the ulnar fracture. The fractures may be incomplete or complete. Although this injury pattern is uncommon in adults and rare in children, the radiocapitellar joint should be examined in all midshaft forearm fractures to avoid missing the proximal radioulnar joint disruption (Fig. 14-17). Failure to recognize the radial head dislocation is the major complication of this fracture.12 
Figure 14-16
Type IV lesion.
 
There is an anterior dislocation of the radial head. The radial and ulnar fractures are usually in the middle third of the shaft, with the radial fracture distal to the ulnar fracture.
There is an anterior dislocation of the radial head. The radial and ulnar fractures are usually in the middle third of the shaft, with the radial fracture distal to the ulnar fracture.
View Original | Slide (.ppt)
Figure 14-16
Type IV lesion.
There is an anterior dislocation of the radial head. The radial and ulnar fractures are usually in the middle third of the shaft, with the radial fracture distal to the ulnar fracture.
There is an anterior dislocation of the radial head. The radial and ulnar fractures are usually in the middle third of the shaft, with the radial fracture distal to the ulnar fracture.
View Original | Slide (.ppt)
X
Figure 14-17
Type IV lesion.
 
A: Anterior dislocation of the radial head with fracture of the proximal third of the radial shaft and an apex anterior ulnar fracture. The dislocation of the radial head was not recognized. B: Five years later, the radial head remained dislocated and was visibly misshapen and prominent. Full range of motion was present, with the exception of a loss of 10 degrees of full supination. The patient had no pain, but generalized weakness was noted in the extremity, especially during throwing motions.
A: Anterior dislocation of the radial head with fracture of the proximal third of the radial shaft and an apex anterior ulnar fracture. The dislocation of the radial head was not recognized. B: Five years later, the radial head remained dislocated and was visibly misshapen and prominent. Full range of motion was present, with the exception of a loss of 10 degrees of full supination. The patient had no pain, but generalized weakness was noted in the extremity, especially during throwing motions.
View Original | Slide (.ppt)
Figure 14-17
Type IV lesion.
A: Anterior dislocation of the radial head with fracture of the proximal third of the radial shaft and an apex anterior ulnar fracture. The dislocation of the radial head was not recognized. B: Five years later, the radial head remained dislocated and was visibly misshapen and prominent. Full range of motion was present, with the exception of a loss of 10 degrees of full supination. The patient had no pain, but generalized weakness was noted in the extremity, especially during throwing motions.
A: Anterior dislocation of the radial head with fracture of the proximal third of the radial shaft and an apex anterior ulnar fracture. The dislocation of the radial head was not recognized. B: Five years later, the radial head remained dislocated and was visibly misshapen and prominent. Full range of motion was present, with the exception of a loss of 10 degrees of full supination. The patient had no pain, but generalized weakness was noted in the extremity, especially during throwing motions.
View Original | Slide (.ppt)
X

Radiographic Evaluation of Monteggia Equivalents

As with the true Bado types, careful radiographic study should be made with at least two orthogonal views of the elbow in addition to standard views of the forearm. Special views such as obliques should be obtained to clearly delineate the associated injuries (e.g., radial head or neck fracture, distal humerus lateral condyle fracture) and allow adequate pretreatment planning. Cross-sectional imaging, such as an MRI or ultrasound scan, should be obtained as needed if further characterization of the injury is required. 

Traumatic Versus Congenital Dislocation

Distinguishing between traumatic and congenital radial head dislocations can be challenging. When radiocapitellar alignment is disrupted radiographically, evaluation of the shape of the radial head and capitellum can help determine the cause of the disruption, especially if there is no history of trauma or the significance of the trauma is questioned. The presence of a hypoplastic capitellum and a convex deformed radial head suggests a congenital etiology (Fig. 14-18).87 True congenital radial head dislocations are usually (but not always) posterior, may be bilateral, and can be associated with various syndromes such as Ehlers–Danlos and nail–patella.3,84 To avoid missing the diagnosis of an acute Monteggia fracture-dislocation, all anterior radial head dislocations should be at least suspected of having a traumatic origin.3,26,84 
Figure 14-18
Congenital versus traumatic dislocation.
 
A: AP elbow radiograph of a 7-year old who presented with limited forearm rotation. B: Lateral elbow radiograph of the elbow of the same child. Note dysplastic radial head, anterior dislocation, and a hypoplastic capitellum. All of these findings are consistent with congenital radial head dislocation. C: AP elbow radiograph of a child with radioulnar synostosis. D: Lateral elbow radiograph of radioulnar synostosis and posterior radial head dislocation. Note posterior bow of the ulna and hypoplasia of the capitellum. This is a case of congenital radioulnar synostosis.
A: AP elbow radiograph of a 7-year old who presented with limited forearm rotation. B: Lateral elbow radiograph of the elbow of the same child. Note dysplastic radial head, anterior dislocation, and a hypoplastic capitellum. All of these findings are consistent with congenital radial head dislocation. C: AP elbow radiograph of a child with radioulnar synostosis. D: Lateral elbow radiograph of radioulnar synostosis and posterior radial head dislocation. Note posterior bow of the ulna and hypoplasia of the capitellum. This is a case of congenital radioulnar synostosis.
View Original | Slide (.ppt)
Figure 14-18
Congenital versus traumatic dislocation.
A: AP elbow radiograph of a 7-year old who presented with limited forearm rotation. B: Lateral elbow radiograph of the elbow of the same child. Note dysplastic radial head, anterior dislocation, and a hypoplastic capitellum. All of these findings are consistent with congenital radial head dislocation. C: AP elbow radiograph of a child with radioulnar synostosis. D: Lateral elbow radiograph of radioulnar synostosis and posterior radial head dislocation. Note posterior bow of the ulna and hypoplasia of the capitellum. This is a case of congenital radioulnar synostosis.
A: AP elbow radiograph of a 7-year old who presented with limited forearm rotation. B: Lateral elbow radiograph of the elbow of the same child. Note dysplastic radial head, anterior dislocation, and a hypoplastic capitellum. All of these findings are consistent with congenital radial head dislocation. C: AP elbow radiograph of a child with radioulnar synostosis. D: Lateral elbow radiograph of radioulnar synostosis and posterior radial head dislocation. Note posterior bow of the ulna and hypoplasia of the capitellum. This is a case of congenital radioulnar synostosis.
View Original | Slide (.ppt)
X

Outcome Measures for Monteggia-Fracture Dislocations

To assess recovery and patient outcome following closed or open treatment of Monteggia lesions, the clinician should carefully measure union rate, time to union, pain, patient satisfaction, elbow flexion and extension, and forearm rotation. Common treatment complications must be accurately recorded, especially because acute Monteggia injuries continue to be missed or inadequately treated, resulting in the development of chronic Monteggia lesions. An improved understanding of return to sports and functional outcomes is critical. The disabilities of the arm, shoulder, and hand (DASH) score can be used to measure the disability following Monteggia fracture-dislocations, but has not been validated in children. Joint-specific outcome measures have been developed for the elbow, but many of these measures would benefit from further research into their validity, reliability, and applicability in children.128 For pediatric patients, the pediatric outcomes data collection instrument (PODCI) offers a validated tool, but its upper limb disability measurement is broad and not joint or disease specific. The development and validation of pediatric upper limb outcome measures is needed. 

Pathoanatomy and Applied Anatomy Relating to Monteggia Fracture-Dislocations

Understanding the anatomy of the proximal radioulnar joint, radiocapitellar joint, and proximal forearm is critical to understanding the treatment of acute and chronic Monteggia lesions. The bony architecture, joint contour, and periarticular ligaments provide stability to the proximal forearm and elbow. The muscle insertions and origins affect stability and determine surgical exposure along with the neighboring neurovascular structures. 

Ligaments

Annular Ligament

The annular (or orbicular) ligament (Fig. 14-19) is one of the prime stabilizers of the proximal radioulnar joint during forearm rotation. The annular ligament encircles the radial neck from its origin and insertion on the proximal ulna. Because of the shape of the radial head, the annular ligament tightens in supination. The annular ligament is confluent with the remainder of the lateral collateral ligamentous complex which provides stability to the radiocapitellar and proximal radioulnar joints and resists varus stress. Displacement of the annular ligament occurs in a Monteggia lesion.144 
Figure 14-19
Ligamentous anatomy of the proximal radioulnar joint.
Flynn-ch014-image019.png
View Original | Slide (.ppt)
X

Quadrate Ligament

The quadrate ligament35,67,153 is just distal to the annular ligament and connects the proximal radius and ulna (Fig. 14-19). It has a dense anterior portion, thinner posterior portion, and even thinner central portion. The quadrate ligament also provides stability to the proximal radioulnar joint during forearm rotation. The anterior and posterior borders become taut at the extremes of supination and pronation, respectively. 

Oblique Cord

The oblique cord (Fig. 14-20), also known as the Weitbrecht ligament, extends at a 45-degree angle from the ulna proximally to the radius distally and is present in approximately 53% of forearms.152 The oblique cord originates just distal to the radial notch of the ulna and inserts just distal to the bicipital tuberosity of the radius. With supination, the oblique cord tightens and may provide a marginal increase in stability to the proximal radioulnar joint. The clinical relevance of this structure is uncertain. 
Figure 14-20
Ligaments of the forearm.
 
In supination, the annular ligament, quadrate ligament, Weitbrecht ligament (oblique cord), and interosseous membrane are taut, providing increased stability to the proximal radioulnar joint.
In supination, the annular ligament, quadrate ligament, Weitbrecht ligament (oblique cord), and interosseous membrane are taut, providing increased stability to the proximal radioulnar joint.
View Original | Slide (.ppt)
Figure 14-20
Ligaments of the forearm.
In supination, the annular ligament, quadrate ligament, Weitbrecht ligament (oblique cord), and interosseous membrane are taut, providing increased stability to the proximal radioulnar joint.
In supination, the annular ligament, quadrate ligament, Weitbrecht ligament (oblique cord), and interosseous membrane are taut, providing increased stability to the proximal radioulnar joint.
View Original | Slide (.ppt)
X

Interosseous Ligament

The interosseous ligament (Fig. 14-20) is distal to the oblique ligament with its primary fibers running in the opposite direction (from radius proximally to ulna distally) to the oblique cord. However, similar to the oblique cord, it tightens in supination and provides further stability to the proximal radioulnar joint. The central band of the interosseous ligament is the stiffest stabilizing structure of the forearm.159 

Bony Architecture

The bony architecture of the elbow creates a relatively constrained hinge. The concave surface of the radial head matches the convex surface of the capitellum and provides stability to the radiocapitellar joint. In contrast, the bony geometry of the proximal radioulnar joint provides minimal inherent stability. 

Radius

The shape of the radial head is generally elliptical in cross section (Fig. 14-21).25 In supination, the long axis of the ellipse is perpendicular to the proximal ulna, causing the annular ligament and the anterior portion of the quadrate ligament to tighten and stabilize the proximal radioulnar joint. In addition, the contact area between the radius and the radial notch of the ulna increases in supination because of the broadened surface of the elliptical radial head proximal to distal in that position. This may provide some additional stability. 
Figure 14-21
The radial head is an elliptical structure secured by the annular ligament, which allows movement while providing stability.
 
Because of the shape of the radial head, the stability provided by the annular ligament is maximized in supination.
Because of the shape of the radial head, the stability provided by the annular ligament is maximized in supination.
View Original | Slide (.ppt)
Figure 14-21
The radial head is an elliptical structure secured by the annular ligament, which allows movement while providing stability.
Because of the shape of the radial head, the stability provided by the annular ligament is maximized in supination.
Because of the shape of the radial head, the stability provided by the annular ligament is maximized in supination.
View Original | Slide (.ppt)
X
The radius “radiates” around the ulna. For this reason, the radius must have an anatomic bow to achieve full forearm rotation while maintaining stability at the proximal and distal radioulnar joints (Fig. 14-21). With the radius in supination, the bow tightens the oblique cord and interosseous ligament, thereby increasing stability of the proximal radioulnar joint. 

Musculature

Biceps Brachii

The biceps brachii inserts into the bicipital tuberosity of the radius and acts as both flexor of the elbow and supinator of the forearm. The biceps acts as a deforming force in anterior Monteggia fracture-dislocations, pulling the radius anteriorly as the elbow is forcibly extended (Fig. 14-9).151 During treatment of type I and type IV lesions, care is taken to maintain the elbow in flexion to prevent recurrent anterior subluxation of the radial head while the soft tissues heal. 

Anconeus

The anconeus may act as a dynamic stabilizer of the elbow joint by providing a valgus moment at the joint during extension and pronation.11,151 It may also act as a deforming force, along with the forearm flexors, on complete fractures of the ulna in a Monteggia lesion. Surgical exposure of the proximal radioulnar and radiocapitellar joints is usually performed through the anconeus–extensor carpi ulnaris interval. 

Nerves

Posterior Interosseous Branch of the Radial Nerve

The radial nerve (Fig. 14-22) passes the distal humerus in the brachialis–brachioradialis interval. As the nerve descends into the forearm, it divides into the superficial radial sensory branch and the posterior interosseous motor branch. The posterior interosseous nerve passes under the Arcade of Frohse (Fig. 14-22) and between the two heads of the supinator, when present, or beneath the supinator when there is only one head. The nerve's close proximity to the radial head and neck makes it susceptible to injury with Monteggia fracture-dislocations.70 Injuries to the posterior interosseous nerve occur more frequently with type III lesions than other types of Monteggia fracture-dislocations.13,119,134 In chronic Monteggia lesions, the posterior interosseous nerve can be adherent to the dislocated radial head or, less commonly, entrapped in the radiocapitellar joint.121 Care must be taken to avoid injury to the radial nerve in surgical reconstructions of the chronic anterior dislocation. 
Figure 14-22
Dissection of the anterior elbow.
 
Note the course of the radial nerve which emerges from the biceps–brachioradialis interval and then divides into the superficial radial sensory branch and the posterior interosseous branch. The posterior interosseous nerve then passes under the Arcade of Frohse.
Note the course of the radial nerve which emerges from the biceps–brachioradialis interval and then divides into the superficial radial sensory branch and the posterior interosseous branch. The posterior interosseous nerve then passes under the Arcade of Frohse.
View Original | Slide (.ppt)
Figure 14-22
Dissection of the anterior elbow.
Note the course of the radial nerve which emerges from the biceps–brachioradialis interval and then divides into the superficial radial sensory branch and the posterior interosseous branch. The posterior interosseous nerve then passes under the Arcade of Frohse.
Note the course of the radial nerve which emerges from the biceps–brachioradialis interval and then divides into the superficial radial sensory branch and the posterior interosseous branch. The posterior interosseous nerve then passes under the Arcade of Frohse.
View Original | Slide (.ppt)
X

Ulnar Nerve

The ulnar nerve passes posterior to the medial intermuscular septum of the arm, through the cubital tunnel behind the medial epicondyle of the distal humerus, and then between both heads of the flexor carpi ulnaris into the forearm. The ulnar nerve is at risk for injury with type II Monteggia lesions because of the stretch associated with varus deformity and also with ulnar lengthening in chronic Monteggia reconstructions. 

General Treatment Principles for Monteggia-Fracture Dislocations

Although most treatment algorithms for Monteggia fracture-dislocations are based on the Bado classification, Ring and Waters119 recommended that treatment choices be based on the type of ulnar fracture rather than on the Bado type. They recommended plastic deformation of the ulna be treated with closed reduction of the ulnar bow to obtain stable reduction of the radiocapitellar joint. Incomplete (greenstick or buckle) fractures of the ulna are similarly treated with closed reduction and casting. In children, most type I Monteggia injuries with plastic deformation of the ulna or incomplete ulnar fractures are stable when immobilized in 100 to 110 degrees of elbow flexion and full forearm supination. 
However, any Monteggia lesion with a complete fracture of the ulna can be unstable after closed reduction. Therefore, with complete transverse or short oblique ulnar fractures or Monteggia lesions associated with a radial fracture (type IV lesions), intramedullary fixation is recommended. Long oblique or comminuted ulnar fractures, which can develop shortening and malalignment even with intramedullary fixation, are best stabilized with plate and screw fixation. Using this treatment protocol, Ring and Waters119 reported excellent results in all 28 patients treated within 24 hours of injury. 
As noted, successful treatment is dependent on three goals: Anatomical correction of the ulnar deformity, achieving a stable congruent reduction of the radiocapitellar joint, and maintenance of ulnar length and fracture stability. For plastic deformation and incomplete fractures, these goals can usually be achieved with closed reduction and cast immobilization. For complete fractures, fracture instability after closed reduction may lead to loss of anatomic ulnar length and redislocation of the radial head. These injuries are generally treated with internal fixation. 

Treatment Options for Type I Monteggia-Fracture Dislocations

Nonoperative Treatment of Type I Monteggia Fracture-dislocations

Indications/Contraindications

Closed reduction and cast immobilization is recommended as an initial treatment strategy for all type I Monteggia fracture-dislocations in which the ulna is plastically deformed or there is an incomplete fracture (greenstick or buckle). Operative intervention is recommended if there is a failure to obtain and maintain ulnar fracture reduction or a failure to obtain and maintain a congruent reduction of the radiocapitellar joint. In patients with complete transverse or oblique fractures of the ulna, closed reduction alone risks loss of reduction in a cast and development of a chronic Monteggia lesion. In these fractures, operative intervention is recommended to facilitate maintenance of ulnar alignment and the radiocapitellar reduction (Table 14-2). 
 
Table 14-2
Monteggia Fracture-dislocations
View Large
Table 14-2
Monteggia Fracture-dislocations
Nonoperative Treatment
Indications Relative Contraindications
Plastic deformation of the ulna Open fracture
Incomplete (greenstick or buckle) ulnar fracture Unstable ulnar fracture pattern
Transverse or short oblique ulnar fracture
Long oblique or comminuted ulnar fracture
Residual or recurrent loss of congruency at radiocapitellar joint
X

Closed Reduction and Immobilization in Type I Monteggia Fracture-Dislocations

Reduction of the Ulnar Fracture

The first step of the closed reduction is to reestablish the length of the ulna by longitudinal traction and manual correction of any angular deformity. The forearm is held in relaxed supination as longitudinal traction is applied with manual pressure directed over the apex of the deformity until the angulation is corrected clinically and radiographically (Figs. 14-23 and 14-24). With plastic deformation fractures, this may necessitate significant force that usually requires general anesthesia. With incomplete fractures, the correction of the ulnar deformity and radial head reduction can often be achieved with conscious sedation in the emergency room. Some papers have cited successful treatment of acute Monteggia lesions (defined as maintenance of the radiocapitellar reduction) with nonanatomic alignment of the ulnar fracture (Fig. 14-25).48,111,113 However, anatomic reduction and healing of the ulna fracture is strongly advocated. 
Figure 14-23
Reduction technique for a type I Monteggia fracture-dislocation.
Flynn-ch014-image023.png
View Original | Slide (.ppt)
X
Figure 14-24
Closed reduction for type I lesion.
 
A: Typical type I lesion in a 7-year old. B: Correction of plastic deformation. Plastic deformation of the ulna must be corrected to prevent recurrence of the angular deformity. C: This allows reduction of the radial head and prevents its late subluxation. (From Wilkins KE, ed. Operative Management of Upper Extremity Fractures in Children. Rosemont, IL: American Academy of Orthopaedic Surgeons; 1994, with permission.) D: The deformity of the ulna is corrected first, and then the elbow is hyperflexed. However, the radial head is still anteriorly subluxed (arrows), and the ulna still has some anterior plastic deformation. This is not acceptable.
A: Typical type I lesion in a 7-year old. B: Correction of plastic deformation. Plastic deformation of the ulna must be corrected to prevent recurrence of the angular deformity. C: This allows reduction of the radial head and prevents its late subluxation. (From Wilkins KE, ed. Operative Management of Upper Extremity Fractures in Children. Rosemont, IL: American Academy of Orthopaedic Surgeons; 1994, with permission.) D: The deformity of the ulna is corrected first, and then the elbow is hyperflexed. However, the radial head is still anteriorly subluxed (arrows), and the ulna still has some anterior plastic deformation. This is not acceptable.
View Original | Slide (.ppt)
Figure 14-24
Closed reduction for type I lesion.
A: Typical type I lesion in a 7-year old. B: Correction of plastic deformation. Plastic deformation of the ulna must be corrected to prevent recurrence of the angular deformity. C: This allows reduction of the radial head and prevents its late subluxation. (From Wilkins KE, ed. Operative Management of Upper Extremity Fractures in Children. Rosemont, IL: American Academy of Orthopaedic Surgeons; 1994, with permission.) D: The deformity of the ulna is corrected first, and then the elbow is hyperflexed. However, the radial head is still anteriorly subluxed (arrows), and the ulna still has some anterior plastic deformation. This is not acceptable.
A: Typical type I lesion in a 7-year old. B: Correction of plastic deformation. Plastic deformation of the ulna must be corrected to prevent recurrence of the angular deformity. C: This allows reduction of the radial head and prevents its late subluxation. (From Wilkins KE, ed. Operative Management of Upper Extremity Fractures in Children. Rosemont, IL: American Academy of Orthopaedic Surgeons; 1994, with permission.) D: The deformity of the ulna is corrected first, and then the elbow is hyperflexed. However, the radial head is still anteriorly subluxed (arrows), and the ulna still has some anterior plastic deformation. This is not acceptable.
View Original | Slide (.ppt)
X
Figure 14-25
 
A: Malaligned ulnar fracture with radial head reduced. B: Subsequent apex posterior angulation healing of ulna fracture while maintaining radial head reduction.
A: Malaligned ulnar fracture with radial head reduced. B: Subsequent apex posterior angulation healing of ulna fracture while maintaining radial head reduction.
View Original | Slide (.ppt)
Figure 14-25
A: Malaligned ulnar fracture with radial head reduced. B: Subsequent apex posterior angulation healing of ulna fracture while maintaining radial head reduction.
A: Malaligned ulnar fracture with radial head reduced. B: Subsequent apex posterior angulation healing of ulna fracture while maintaining radial head reduction.
View Original | Slide (.ppt)
X

Reduction of the Radial Head

Once ulnar length and alignment have been reestablished, the radial head can be relocated. This is often accomplished by simply flexing the elbow to 90 degrees or more, thus producing spontaneous reduction (Fig. 14-26). Occasionally, posteriorly directed pressure over the anterior aspect of the radial head is necessary for reduction of the radial head. Flexion of the elbow to 110 to 120 degrees stabilizes the reduction. Once the radial head position is established, it should be scrutinized radiographically in numerous views to ensure a concentric reduction. With a type I lesion, the optimal radiographic view is a true lateral of the elbow with the forearm held in supination. The longitudinal axis of the radius should pass directly through the center of the capitellum (Fig. 14-26). 
Figure 14-26
Schematic reduction maneuvers for type I lesion.
 
Flexing the elbow spontaneously reduces the radial head. Occasionally, manual pressure is required in combination with flexion.
Flexing the elbow spontaneously reduces the radial head. Occasionally, manual pressure is required in combination with flexion.
View Original | Slide (.ppt)
Figure 14-26
Schematic reduction maneuvers for type I lesion.
Flexing the elbow spontaneously reduces the radial head. Occasionally, manual pressure is required in combination with flexion.
Flexing the elbow spontaneously reduces the radial head. Occasionally, manual pressure is required in combination with flexion.
View Original | Slide (.ppt)
X

Radiographic Evaluation and Immobilization

Once the concentric reduction of the radial head is confirmed, the elbow should be placed in approximately 110 to 120 degrees of flexion to alleviate the force of the biceps, which could redislocate the radial head. The forearm is placed in a position of midsupination to neutral rotation to alleviate the forces of the biceps, supinator muscle and the anconeus, as well as the forearm flexors, which tend to produce radial angulation of the ulna. After the fracture is reduced and the position of stability is established, a molded long arm splint or cast is applied to hold the elbow joint in the appropriate amount of flexion, usually 110 to 120 degrees. Once the casting is completed, careful radiographic assessment should establish the concentric reduction of the radial head with respect to the capitellum, as well as satisfactory alignment of the ulna (Fig. 14-27). 
Figure 14-27
 
Once the close reduction is complete, radiographs should be analyzed for reestablishment of the radiocapitellar line (arrows) and ulnar alignment on both the lateral (A) and Jones (B) views.
Once the close reduction is complete, radiographs should be analyzed for reestablishment of the radiocapitellar line (arrows) and ulnar alignment on both the lateral (A) and Jones (B) views.
View Original | Slide (.ppt)
Figure 14-27
Once the close reduction is complete, radiographs should be analyzed for reestablishment of the radiocapitellar line (arrows) and ulnar alignment on both the lateral (A) and Jones (B) views.
Once the close reduction is complete, radiographs should be analyzed for reestablishment of the radiocapitellar line (arrows) and ulnar alignment on both the lateral (A) and Jones (B) views.
View Original | Slide (.ppt)
X

Postreduction Care

The patient is followed at 1- to 2-week intervals to confirm continued satisfactory reduction by radiography. At 4 to 6 weeks after the initial reduction, if there is radiographic evidence of consolidation of the ulnar fracture and stability of the radial head, the long-arm cast can be removed with progressive guarded return to full activity. A final set radiographs should be obtained when the patient has achieved full motion to be certain the radiocapitellar and proximal radioulnar joints remain anatomically aligned. 

Outcomes of Nonoperative Treatment

In all series,4,10,21,22,38,48,81,98,116,119,127,160 type I Monteggia lesions in children have uniformly good results when treated by manipulative closed reduction, if the radial head is properly aligned and the ulnar fracture is reduced with length preserved. These results most clearly apply to plastic deformation and incomplete fractures, which make up the majority of type I Monteggia lesions. No deterioration of results appears to occur at long-term.79,101 

Operative Treatment of Type I Monteggia Fracture-dislocations

Indications

There are two principal indications for operative treatment of type I fracture-dislocations: Failure to obtain and maintain ulnar fracture reduction or a failure to obtain and maintain a congruent reduction of the radiocapitellar joint. The fractures most at risk for loss of reduction with nonoperative management are complete ulnar fractures. In these fractures, operative fixation of the ulna is recommended to facilitate maintenance of ulnar alignment and radiocapitellar reduction. In some cases, closed reduction of the radiocapitellar joint cannot be achieved, even after intramedullary or plate fixation of the ulna. It is important not to accept a nonanatomic reduction as an imperfect reduction which can result in further joint malalignment and the development of a chronic Monteggia lesion. In these cases, the annular ligament is almost always avulsed or entrapped.144 There is a high likelihood that annular ligament and/or periosteal interposition is preventing congruent reduction of the radiocapitellar joint. In these situations, an open reduction of the radiocapitellar joint should be performed with restoration of the annular ligament to its normal position.144,151 Routine preoperative planning is required before embarking on any of the operative treatment pathways described below (Table 14-3). 
 
Table 14-3
Operative Treatment of Monteggia Fracture-dislocations
View Large
Table 14-3
Operative Treatment of Monteggia Fracture-dislocations
Preoperative Planning Checklist
  •  
    Standard OR table with radiolucent arm board, table turned 90 degrees with operative limb pointing toward operating room
  •  
    Position: Patient supine with adequate padding of heels and other bony prominences
  •  
    Fluoroscopy location: Generally from below arm (medial to lateral)
  •  
    Equipment: Standard operating instruments, drill, K-wire or flexible titanium nail set, small fragment set, nonabsorbable 2–0 and 3–0 suture, splinting or casting supplies
  •  
    Tourniquet (sterile/nonsterile): Surgeon's preference, nonsterile tourniquet generally sufficient
  •  
    Standard preoperative verification
X

Intramedullary Fixation of Transverse or Short Oblique Ulnar Fractures

In patients with complete transverse or short oblique fractures, closed reduction alone can result in loss of reduction in a cast. In these cases, closed reduction and intramedullary fixation of the ulna is recommended to facilitate maintenance of ulnar alignment and length along with reduction of the radiocapitellar joint. The quality of the ulnar reduction affects the ability to reduce the radial head, which is of primary importance. If an ulnar fracture can be reduced but not maintained because of the obliquity of the fracture, internal fixation is also indicated.48,98 Intramedullary fixation is standard in most series of Monteggia fracture-dislocations in children (Fig. 14-28).8,10,38,47,48,76,78,85,98,112,119,122,138,160 Percutaneous intramedullary fixation reliably maintains alignment and preserves length without the additional concerns of open surgery or implant retention. This method of fixation can be accomplished using image intensification and with a Kirschner wire (K-wire) or a flexible titanium nail (Synthes, West Chester, PA). K-wires have the advantage of being universally available and inexpensive. Their stainless steel composition and smooth tip also permit easy removal in the office without need for additional anesthesia. Note that K-wires may not be of sufficient length for use in older children with longer forearms. Entry can be through the apophysis or proximal metaphysis of the ulna, depending on the level of the fracture and surgeon's preference. For type I lesions, a closed reduction maneuver is performed as described above. At times, an intramedullary K-wire or nail in the proximal fragment can be used to joystick the reduction. Intraoperative fluoroscopy is utilized to confirm appropriate ulnar and radiocapitellar reduction, as well as proper interosseous placement of the intramedullary device. Because ulnar fractures heal rapidly in children, the intramedullary device can generally be bent and cut outside of the skin to facilitate subsequent office removal. Some surgeons prefer to leave the intramedullary rod in a long time and therefore bury it beneath the skin. A long arm splint or bivalved cast is then applied with the elbow in 90 to 110 degrees of flexion and forearm supination, which provides additional stability to the radiocapitellar joint (Table 14-4). 
Figure 14-28
 
A: Short oblique ulna fracture on AP view. B: Lateral view reveals anterior radial head dislocation (Bado I). C: Closed reduction of ulna fracture in OR with radial head reduction. D: Entry site via olecranon apophysis for longitudinal pin. E: Stable reduction of ulna fracture with anatomic reduction radial head on lateral and (F) AP views. G: Healed ulna diaphyseal fracture after smooth pin removal and maintenance of radial head reduction.
 
(From Bae DS, Waters P M. Pediatric Hand and Upper Limb Surgery: A Practical Guide. Philadelphia, PA: Lippincott Williams & Wilkins; 2012, with permission).
A: Short oblique ulna fracture on AP view. B: Lateral view reveals anterior radial head dislocation (Bado I). C: Closed reduction of ulna fracture in OR with radial head reduction. D: Entry site via olecranon apophysis for longitudinal pin. E: Stable reduction of ulna fracture with anatomic reduction radial head on lateral and (F) AP views. G: Healed ulna diaphyseal fracture after smooth pin removal and maintenance of radial head reduction.
View Original | Slide (.ppt)
A: Short oblique ulna fracture on AP view. B: Lateral view reveals anterior radial head dislocation (Bado I). C: Closed reduction of ulna fracture in OR with radial head reduction. D: Entry site via olecranon apophysis for longitudinal pin. E: Stable reduction of ulna fracture with anatomic reduction radial head on lateral and (F) AP views. G: Healed ulna diaphyseal fracture after smooth pin removal and maintenance of radial head reduction.
View Original | Slide (.ppt)
Figure 14-28
A: Short oblique ulna fracture on AP view. B: Lateral view reveals anterior radial head dislocation (Bado I). C: Closed reduction of ulna fracture in OR with radial head reduction. D: Entry site via olecranon apophysis for longitudinal pin. E: Stable reduction of ulna fracture with anatomic reduction radial head on lateral and (F) AP views. G: Healed ulna diaphyseal fracture after smooth pin removal and maintenance of radial head reduction.
(From Bae DS, Waters P M. Pediatric Hand and Upper Limb Surgery: A Practical Guide. Philadelphia, PA: Lippincott Williams & Wilkins; 2012, with permission).
A: Short oblique ulna fracture on AP view. B: Lateral view reveals anterior radial head dislocation (Bado I). C: Closed reduction of ulna fracture in OR with radial head reduction. D: Entry site via olecranon apophysis for longitudinal pin. E: Stable reduction of ulna fracture with anatomic reduction radial head on lateral and (F) AP views. G: Healed ulna diaphyseal fracture after smooth pin removal and maintenance of radial head reduction.
View Original | Slide (.ppt)
A: Short oblique ulna fracture on AP view. B: Lateral view reveals anterior radial head dislocation (Bado I). C: Closed reduction of ulna fracture in OR with radial head reduction. D: Entry site via olecranon apophysis for longitudinal pin. E: Stable reduction of ulna fracture with anatomic reduction radial head on lateral and (F) AP views. G: Healed ulna diaphyseal fracture after smooth pin removal and maintenance of radial head reduction.
View Original | Slide (.ppt)
X
Table 14-4
Intramedullary Fixation of Transverse or Short Oblique Ulnar Fractures
Surgical Steps
  •  
    Cortical entry through the apophysis or proximal metaphysis of the ulna
  •  
    Introduce appropriately sized intramedullary device (K-wire or flexible titanium nail)
  •  
    Perform closed reduction based on mechanism of injury
    •  
      Intramedullary device can be used in the proximal fragment to joystick the reduction
  •  
    Stabilize fracture with the intramedullary device, utilize fluoroscopy to confirm appropriate ulnar and radiocapitellar reduction, as well as proper placement of the intramedullary device
  •  
    Bend and cut intramedullary K-wire outside of skin to facilitate subsequent removal in the office; titanium nails or buried wires need to be removed in day surgery unit
  •  
    Apply long arm splint or bivalved cast in a position of elbow flexion and supination appropriate for the specific Bado type
X

Open Reduction and Plate Fixation of Long Oblique or Comminuted Ulnar Fractures

Although intramedullary fixation is preferred for transverse and short oblique fractures, long oblique and comminuted fractures may redisplace even with intramedullary fixation.119 Plate and screw fixation (Fig. 14-29) is preferred with these rarer fractures.78,104,109,119,148,154,162 A longitudinal incision, centered at the apex of the fracture, is made along the subcutaneous border of the ulna, at the extensor carpi ulnaris–flexor carpi ulnaris interval. An open reduction is performed, and a double-stacked one-third tubular plate or 3.5-mm dynamic compression plate (Synthes, West Chester, PA) is applied utilizing standard AO techniques. Four to six cortices of fixation is generally required both proximal and distal to the fracture. Intraoperative fluoroscopy is used to confirm appropriate ulnar and radiocapitellar reduction. The periosteum is repaired over the fracture site and implant. Again, a long arm splint or bivalved cast is then applied with the elbow in 90 to 110 degrees of flexion and forearm supination, which provides additional stability to the radiocapitellar joint (Table 14-5). 
Figure 14-29
ORIF of Monteggia lesion in a 4-year-old male associated with a comminuted ulna fracture.
 
A, B: Injury radiographs demonstrating the dislocated radial head and ulnar fracture pattern. C, D: Radiographs taken 3 months postoperatively, demonstrating a healed fracture and stable joint alignment.
 
(From Bae DS, Waters PM. Pediatric Hand and Upper Limb Surgery: A Practical Guide. Philadelphia, PA: Lippincott Williams & Wilkins; 2012, with permission).
A, B: Injury radiographs demonstrating the dislocated radial head and ulnar fracture pattern. C, D: Radiographs taken 3 months postoperatively, demonstrating a healed fracture and stable joint alignment.
View Original | Slide (.ppt)
Figure 14-29
ORIF of Monteggia lesion in a 4-year-old male associated with a comminuted ulna fracture.
A, B: Injury radiographs demonstrating the dislocated radial head and ulnar fracture pattern. C, D: Radiographs taken 3 months postoperatively, demonstrating a healed fracture and stable joint alignment.
(From Bae DS, Waters PM. Pediatric Hand and Upper Limb Surgery: A Practical Guide. Philadelphia, PA: Lippincott Williams & Wilkins; 2012, with permission).
A, B: Injury radiographs demonstrating the dislocated radial head and ulnar fracture pattern. C, D: Radiographs taken 3 months postoperatively, demonstrating a healed fracture and stable joint alignment.
View Original | Slide (.ppt)
X
Table 14-5
Open Reduction and Plate Fixation of Long Oblique or Comminuted Ulnar Fractures
Surgical Steps
  •  
    Longitudinal incision over subcutaneous border of the ulna
  •  
    Develop interval between extensor carpi ulnaris and flexor carpi ulnaris
  •  
    Carefully incise periosteum and preserve for subsequent repair
  •  
    Perform open reduction
  •  
    Apply double-stacked one-third tubular plate or 3.5-mm dynamic compression plate
    •  
      Four to six cortices of fixation both proximal and distal to the fracture
  •  
    Utilize fluoroscopy to confirm appropriate ulnar and radiocapitellar reduction, as well as proper placement of the plate and screws
  •  
    Repair periosteum over the fracture site and implant
  •  
    Layered wound closure
  •  
    Apply long arm splint or bivalved cast in a position of elbow flexion and supination appropriate for the specific Bado type
X

Open Reduction of the Annular Ligament

On occasion, a congruent closed reduction of the radiocapitellar joint cannot be achieved, even after intramedullary fixation or plate fixation of the ulna. In these situations, the position of the radial head may be improved, but the reduction remains imperfect. The surgeon may not feel a definitive clunk associated with an anatomic reduction, and instead may feel a soft or rubbery resistance during manipulation. This suggests soft tissue interposition of either the annular ligament and/or periosteum.151,162 An open reduction of the radiocapitellar joint with restoration of the annular ligament to its normal position is recommended (Fig. 14-30). Soft tissue interposition more commonly occurs in type III lesions, but can also occur in type I lesions. Interposed cartilaginous or osteochondral fractures in the radiocapitellar joint or proximal radioulnar joint may also prevent complete reduction of the radial head.151 Morris92 described a patient in whom reduction of the radial head was obstructed by radial nerve entrapment between the radial head and ulna. 
Figure 14-30
Open reduction of the radial head.
 
A: Intraoperative photograph of a left elbow, depicting a dislocated radial head identified via a posterolateral approach. B: A Freer elevator has been placed into the middle of the annular ligament, which can then be reduced over the radial head and neck.
 
(From Bae DS, Waters PM. Pediatric Hand and Upper Limb Surgery: A Practical Guide. Philadelphia, PA: Lippincott Williams & Wilkins; 2012, with permission)
A: Intraoperative photograph of a left elbow, depicting a dislocated radial head identified via a posterolateral approach. B: A Freer elevator has been placed into the middle of the annular ligament, which can then be reduced over the radial head and neck.
View Original | Slide (.ppt)
Figure 14-30
Open reduction of the radial head.
A: Intraoperative photograph of a left elbow, depicting a dislocated radial head identified via a posterolateral approach. B: A Freer elevator has been placed into the middle of the annular ligament, which can then be reduced over the radial head and neck.
(From Bae DS, Waters PM. Pediatric Hand and Upper Limb Surgery: A Practical Guide. Philadelphia, PA: Lippincott Williams & Wilkins; 2012, with permission)
A: Intraoperative photograph of a left elbow, depicting a dislocated radial head identified via a posterolateral approach. B: A Freer elevator has been placed into the middle of the annular ligament, which can then be reduced over the radial head and neck.
View Original | Slide (.ppt)
X
The most direct approach to the radiocapitellar joint is from the posterolateral aspect of the elbow. The interval between the anconeus and the extensor carpi ulnaris, using the distal portion of a Kocher incision, provides sufficient exposure of the radial head and the interposed structures.56,139 This approach protects the posterior interosseous nerve when the forearm is pronated. A more extensile approach was described by Boyd (Fig. 14-31).20 This exposure is begun by making an incision following the lateral border of the triceps posteriorly to the lateral condyle and extending it along the radial side of the ulna. The incision is carried under the anconeus and extensor carpi ulnaris in an extraperiosteal manner, elevating the fibers of the supinator from the ulna. This carries the approach down to the interosseous membrane, allowing exposure of the radiocapitellar joint, excellent visualization of the annular ligament, access to the proximal fourth of the entire radius, and approach to the ulnar fracture all through the same incision.20,21,131 In addition, elevation of the extensor–supinator mass from the lateral epicondyle allows more proximal exposure of the dislocated radial head if entrapped behind the displaced capsule and annular ligament. 
Figure 14-31
Boyd approach.
 
A: The incision is carried under the anconeus and extensor carpi ulnaris to expose the radial head and annular ligament. B: The incision can be extended distally to allow exposure of the ulnar fracture and proximally to facilitate harvesting of a fascial strip for annular ligament reconstruction, if necessary.
A: The incision is carried under the anconeus and extensor carpi ulnaris to expose the radial head and annular ligament. B: The incision can be extended distally to allow exposure of the ulnar fracture and proximally to facilitate harvesting of a fascial strip for annular ligament reconstruction, if necessary.
View Original | Slide (.ppt)
Figure 14-31
Boyd approach.
A: The incision is carried under the anconeus and extensor carpi ulnaris to expose the radial head and annular ligament. B: The incision can be extended distally to allow exposure of the ulnar fracture and proximally to facilitate harvesting of a fascial strip for annular ligament reconstruction, if necessary.
A: The incision is carried under the anconeus and extensor carpi ulnaris to expose the radial head and annular ligament. B: The incision can be extended distally to allow exposure of the ulnar fracture and proximally to facilitate harvesting of a fascial strip for annular ligament reconstruction, if necessary.
View Original | Slide (.ppt)
X
After obtaining adequate surgical exposure through either approach, a capsulotomy is performed and the elbow joint is inspected. Careful exploration is required to identify the annular ligament. The ligament is not typically torn in its midsubstance, but rather remains in continuity and tears of the ulna with a periosteal sleeve. Once the opening in the annular ligament is identified, a Freer elevator, forceps, soft tissue probe, or a small curette is used to reduce the annular ligament over the radial head. If a repair is required, 2-0 or 3-0 nonabsorbable sutures can be utilized. The congruency of the radiocapitellar reduction should be confirmed under direct visualization. Stability can then be confirmed by rotating the forearm under careful fluoroscopic imaging. If the radial head is still unstable, look for missed plastic deformation of the ulna. If present, closed reduction of the ulna, or at times opening wedge osteotomy of the ulna, is required to anatomically and stably reduce the radial head. A layered wound closure is performed, followed by application of a long arm splint or bivalved cast with the forearm in supination (Table 14-6). 
 
Table 14-6
Open Reduction of Annular Ligament
View Large
Table 14-6
Open Reduction of Annular Ligament
Surgical Steps
  •  
    Posterolateral (Kocher) approach to the elbow under tourniquet control
  •  
    Develop interval between extensor carpi ulnaris and anconeus, maintain forearm in pronation to protect radial nerve from iatrogenic injury
  •  
    Perform elbow capsulotomy
  •  
    Identify annular ligament
    •  
      Ligament typically in continuity, usually torn off the ulna with a periosteal sleeve (generally not torn midsubstance)
  •  
    Reduce annular ligament over the radius, repair as needed with 2–0 and/or 3–0 nonabsorbable suture
  •  
    Layered wound closure
  •  
    Apply long arm splint or bivalved cast in a position of elbow flexion and supination appropriate for the specific Bado type
X

Author's Preferred Treatment for Type I Monteggia-Fracture Dislocations

An anatomic, stable reduction of the ulnar fracture almost always leads to a stable reduction of the radiocapitellar joint (Fig. 14-32). This in turn leads to an excellent long-term outcome. Failure to obtain and maintain ulnar fracture and radiocapitellar reduction will lead to a chronic Monteggia lesion, which is a complex clinical and surgical problem with risk of a suboptimum outcome. Therefore, we are very aggressive in treatment of acute Monteggia fracture-dislocations. Percutaneous intramedullary fixation of complete transverse and short oblique ulna fractures is standard. Open reduction and internal fixation with plate and screws of the rarer long oblique and comminuted fracture is also standard. Any irreducible or unstable radial head after fracture reduction and stabilization is approached surgically to define and correct the cause. This usually involves reducing an interposed annular ligament. This aggressive approach avoids late complications.119 
Flynn-ch014-image032.png
View Original | Slide (.ppt)
Figure 14-32
Author's preferred treatment algorithm.
Flynn-ch014-image032.png
View Original | Slide (.ppt)
X
After closed or open reduction of the ulna fracture and closed or open reduction of the radial head, a bivalved long-arm cast is used for 4 to 6 weeks with the forearm in slight supination and the elbow flexed 90 to 110 degrees depending on the degree of swelling. Radiographs are obtained every 1 to 2 weeks until fracture healing. Intramedullary hardware is removed with fracture healing. Plate and screw fixation is removed after 6 to 12 months, only if resulting in discomfort. Home rehabilitation is begun at 6 weeks and return to sports is dependent on restoration of motion and strength (Table 14-7). 
 
Table 14-7
Monteggia Fracture-dislocations
View Large
Table 14-7
Monteggia Fracture-dislocations
Potential Pitfalls and Preventions
Pitfall Preventions
Failure to identify radial head dislocation leading to chronic Monteggia lesion Always obtain dedicated elbow radiographs with forearm fractures to evaluate congruency of radiocapitellar reduction
Loss of radiocapitellar reduction leading to chronic Monteggia lesion Intramedullary fixation or plate fixation for unstable ulnar fractures
Regular postoperative radiographs every 1–2 weeks until fracture healing
Inadequate reduction of radial head leading to chronic Monteggia lesion Never accept an imperfect reduction of the radial head, always perform an open reduction of radiocapitellar joint with restoration of the annular ligament to its normal position
Radial nerve palsy During posterolateral approach to the elbow, pronate forearm to protect radial nerve from iatrogenic injury
During chronic Monteggia reconstructions, identify and protect radial nerve
Compartment syndrome Monitor high-energy injuries in hospital with frequent neurovascular monitoring
Perform prophylactic volar and dorsal forearm fasciotomies during chronic Monteggia reconstructions
Consider bivalving postoperative casts
X

Treatment Options for Type II Monteggia-Fracture Dislocations

Indications for Treatment of Type II Monteggia Fracture-Dislocations

The indications for nonoperative and operative treatment of type II lesions are similar to type I lesions as the ulnar fracture pattern dictates initial decision making. Following ulnar fracture reduction, any residual lack of congruency at the radiocapitellar joint should be treated surgically. 

Nonoperative Treatment of Type II Monteggia Fracture-dislocations

As with type I injuries, incomplete type II fractures usually have a satisfactory result after closed reduction.81,98,106,113,160 The ulnar fracture is reduced by longitudinal traction in line with the long axis of the forearm while the elbow is held at 60 degrees of flexion (Fig. 14-33). The radial head may reduce spontaneously or may require gentle, anteriorly directed pressure applied to its posterior aspect. The elbow is extended once the radial head is reduced; is immobilized in that position to stabilize the radial head and allow molding posteriorly to maintain the ulnar reduction.38,106,155 If the ulnar alignment cannot be maintained, an intramedullary K-wire should be used. 
Figure 14-33
Schematic reduction maneuvers for type II lesion.
 
Longitudinal traction and pronation of the forearm and immobilization in 60-degree flexion or complete extension.
Longitudinal traction and pronation of the forearm and immobilization in 60-degree flexion or complete extension.
View Original | Slide (.ppt)
Figure 14-33
Schematic reduction maneuvers for type II lesion.
Longitudinal traction and pronation of the forearm and immobilization in 60-degree flexion or complete extension.
Longitudinal traction and pronation of the forearm and immobilization in 60-degree flexion or complete extension.
View Original | Slide (.ppt)
X

Operative Treatment of Type II Monteggia Fracture-dislocations

Treatment goals are stable concentric reduction of the radial head and alignment of the ulnar fracture. When there is an unstable, complete ulnar fracture, percutaneous intramedullary fixation or open reduction and internal fixation with plate and screws are used similar to type I Monteggia fracture-dislocations.104,109 The radial head should be reduced by open technique if there is interposed soft tissue or the Monteggia lesion is accompanied by a fractured capitellum or radial head. 

Author's Preferred Treatment for Type II Monteggia Fracture-Dislocations

With incomplete fractures, ulnar length is reestablished by applying longitudinal traction and straightening the angular deformity (Fig. 14-33). The radial head may reduce spontaneously or with gentle, anteriorly directed force over the radial head. Once reduced, the position of the head can be stabilized by holding the elbow in extension. If the ulnar fracture is stable, it can be maintained by cast immobilization with the elbow in extension. However, if there is any doubt, percutaneous intramedullary fixation is preferred. Comminuted or very proximal fractures may require open reduction and internal fixation with plate and screws or tension band fixation. Postoperative radiographs are obtained approximately every 7 to 14 days to confirm continued reduction of the radial head. 
The Boyd approach (Fig. 14-31) can be used to obtain reduction of the radial head if it cannot be obtained through closed manipulation. Management of the annular ligament is the same as described for type I Monteggia lesions. Associated compression fractures of the radial head require early detection to avoid late loss of alignment. Open reduction and internal fixation may be required to maintain radiocapitellar joint stability. Osteonecrosis and nonunion are complications of this rare injury pattern. Cast immobilization is continued until fracture and soft tissue healing, usually 6 weeks. Home rehabilitation is performed until restoration of motion and strength.106 

Treatment Options for Type III Monteggia Fracture-Dislocations

Indications for Treatment of Type III Monteggia Fracture-Dislocations

Like type I lesions, there are two principal indications for operative treatment of type III fracture-dislocations: Failure to obtain and maintain ulnar fracture reduction or a failure to obtain and maintain a congruent reduction of the radiocapitellar joint. Soft tissue interposition more commonly occurs in type III lesions, and open reduction of the radial head may be required more frequently as a consequence.13,63,119,145,162,163 Nonoperative treatment by manipulative closed reduction is usually effective in pediatric patients with metaphyseal, incomplete, or plastic deformation fractures.10,38,50,63,81,93,98,106,146,160,163 However, the rate of operative treatment has been reported to be as high as 12%.98 

Nonoperative Treatment of Type III Monteggia Fracture-dislocations

Closed Reduction

A closed reduction is carried out by reversing the mechanism of injury.38,93,106,147 The elbow is held in extension with longitudinal traction. Valgus stress is placed on the ulna at the fracture site, restoring anatomic realignment (Fig. 14-34). The radial head may spontaneously reduce or may need assistance with gentle pressure applied laterally (Fig. 14-35). Reduction of the radial head sometimes produces a palpable click.147 Ulnar length and alignment must be nearly anatomic to ensure stability of the radial head.48 Fluoroscopic radiographs are obtained to confirm radial head reduction.90 Stability of the ulnar fracture is tested. Any malalignment of the radiocapitellar joint in any view implies the possibility of interposed tissue or persistent malalignment of the ulna fracture. 
Flynn-ch014-image034.png
View Original | Slide (.ppt)
Figure 14-34
Schematic reduction maneuvers for type III lesion.
Flynn-ch014-image034.png
View Original | Slide (.ppt)
X
Figure 14-35
Reduction of type III lesion.
 
Valgus stress is placed on the ulna at the fracture site (arrows), producing clinical realignment. The radial head may spontaneously reduce.
Valgus stress is placed on the ulna at the fracture site (arrows), producing clinical realignment. The radial head may spontaneously reduce.
View Original | Slide (.ppt)
Figure 14-35
Reduction of type III lesion.
Valgus stress is placed on the ulna at the fracture site (arrows), producing clinical realignment. The radial head may spontaneously reduce.
Valgus stress is placed on the ulna at the fracture site (arrows), producing clinical realignment. The radial head may spontaneously reduce.
View Original | Slide (.ppt)
X

Radiographic Evaluation and Immobilization

Radiographs are taken in the AP and lateral planes to confirm the reduction of the radial head and assess the ulnar alignment. Up to 10 degrees of ulnar angulation is acceptable in younger children, provided the radial head reduction is concentric and stable. Range-of-motion testing of stability is appropriate and necessary with plastic deformation fractures because radiocapitellar alignment can be difficult to assess AP radiographs in the cast. 
Reduction is maintained by the application of a long arm splint, cast or bivalved cast with a valgus mold and with the elbow in relative flexion. The degree of flexion varies depending on the direction of the radial head dislocation. When the radial head is dislocated in a straight lateral or anterolateral position, flexion to 100 to 110 degrees improves stability.41,93,113,160 If there is a posterolateral component to the dislocation, flexion to 70 to 80 degrees has been recommended.147 Forearm rotation in the cast is usually in supination, which tightens the interosseous membrane and further stabilizes the reduction.10,38,93,160 Some have suggested positions of immobilization from pronation146 to slight supination.147 Ramsey and Pedersen113 recommended neutral as the best position of rotation to avoid loss of motion; their patients showed no loss of reduction using this position. It must be emphasized that the ulnar fracture and radial head reduction need to be truly stable for closed treatment because postreduction radiographs in cast are difficult to interpret accurately. 

Postreduction Care

Cast immobilization is continued until fracture and soft tissue healing, usually by 6 weeks. Home rehabilitation is performed until restoration of motion and strength. A final set of radiographs are obtained when the patient has achieved full motion and strength to be certain that there is continued anatomic reduction of the proximal radioulnar and radiocapitellar joints. 

Operative Treatment of Type III Monteggia Fracture-dislocations

As noted earlier, the goals of surgical intervention are reduction and stabilization of both the ulnar fracture and the radial head. If there is an inability to obtain and maintain anatomic alignment of the ulnar fracture, proximal radioulnar joint, or radiocapitellar joint, then operative treatment is clearly indicated. 

Ulnar Stabilization

Ulnar malalignment may prevent anatomic relocation of the radial head. The ulnar fracture can usually be reduced closed, but internal fixation may be necessary if the ulnar fracture is unstable to prevent recurrent lateral dislocation of the radial head. Persistent varus alignment, particularly with oblique ulnar fractures, can lead to recurrent subluxation of the radial head, radiocapitellar incongruency and risk of a poor outcome (Fig. 14-15).48,98 Anatomic reduction of the ulna and fixation with plates and screws48 or intramedullary wires8 will yield excellent results. 

Open Reduction of the Annular Ligament

Failed closed reduction of the radial head with anatomic alignment of the ulna fracture implies interposition of soft tissue, which is repaired through a Boyd approach (Fig. 14-31).20,162 This allows removal of the interposed tissues151,162 and repair or reconstruction of the annular ligament and the periosteum of the ulna as necessary (Fig. 14-36),14,23,48,50,131,145 The surgical technique is essentially the same as previously described for a type I Monteggia fracture-dislocation. 
Figure 14-36
Irreducible type III lesion.
 
A: Injury films showing typical greenstick olecranon fracture and lateral dislocation of a type III lesion. B: After manipulation and correction of the ulnar deformity, the radial head still remained dislocated. C: An open reduction was performed to extract the interposed torn annular ligament.
A: Injury films showing typical greenstick olecranon fracture and lateral dislocation of a type III lesion. B: After manipulation and correction of the ulnar deformity, the radial head still remained dislocated. C: An open reduction was performed to extract the interposed torn annular ligament.
View Original | Slide (.ppt)
Figure 14-36
Irreducible type III lesion.
A: Injury films showing typical greenstick olecranon fracture and lateral dislocation of a type III lesion. B: After manipulation and correction of the ulnar deformity, the radial head still remained dislocated. C: An open reduction was performed to extract the interposed torn annular ligament.
A: Injury films showing typical greenstick olecranon fracture and lateral dislocation of a type III lesion. B: After manipulation and correction of the ulnar deformity, the radial head still remained dislocated. C: An open reduction was performed to extract the interposed torn annular ligament.
View Original | Slide (.ppt)
X

Author's Preferred Treatment for Type III Monteggia Fracture-Dislocations

As with any Monteggia lesion, treatment is primarily aimed at obtaining and maintaining reduction of the radial head, either by an open or closed technique. This is usually performed by anatomic, stable closed reduction of the ulnar fracture that in turn leads to a stable reduction of the proximal radioulnar and radiocapitellar joints. 

Treatment Options for Type IV Monteggia Fracture-Dislocations

Indications for Treatment of Type IV Monteggia Fracture-Dislocations

This complex lesion has been treated by both closed98 and open10 techniques. Percutaneous intramedullary fixation of the radial and ulnar fractures with flexible pins and closed reduction of the radial head also have been described.51,120 The goals of treatment for a type IV Monteggia lesion are similar to those of other Bado types. The presence of the free-floating proximal radial fragment hampers the ability to reduce the radial head. Stabilization of the radial fracture converts a type IV lesion to a type I lesion, making treatment simpler. 

Nonoperative Treatment of Type IV Monteggia Fracture-dislocations

Closed reduction should be attempted initially, with the aim of transforming the type IV lesion to a type I lesion (Fig. 14-37), especially if the radial and ulnar fractures have greenstick patterns. Use of the image intensifier allows immediate confirmation of reduction, especially of the radial head. Closed treatment of unstable ulnar lesions should not be attempted. If the initial fracture reduction cannot be obtained, an anatomic stable reduction with either intramedullary or plate fixation is performed. 
Flynn-ch014-image037.png
View Original | Slide (.ppt)
Figure 14-37
Schematic reduction maneuvers for type IV lesion.
Flynn-ch014-image037.png
View Original | Slide (.ppt)
X

Operative Treatment of Type IV Monteggia Fracture-dislocations

Type IV fractures are usually unstable and the reduction of the radial head is easier to obtain and maintain after stable fixation of the radius. In young patients, this may be achieved by intramedullary fixation. In children older than 12 years, plating of the radius through a volar Henry extensile approach59 provides more rigid stabilization (Fig. 14-38). Once stability is achieved, a closed reduction of the radial head is attempted. This is usually successful, but any intra-articular obstruction can be removed through a Boyd approach (Fig. 14-31). 
Figure 14-38
Operative treatment, type IV lesion.
 
The initial goal is to stabilize the radius. In older children, a plate may be indicated. Intramedullary pinning usually is adequate.
The initial goal is to stabilize the radius. In older children, a plate may be indicated. Intramedullary pinning usually is adequate.
View Original | Slide (.ppt)
Figure 14-38
Operative treatment, type IV lesion.
The initial goal is to stabilize the radius. In older children, a plate may be indicated. Intramedullary pinning usually is adequate.
The initial goal is to stabilize the radius. In older children, a plate may be indicated. Intramedullary pinning usually is adequate.
View Original | Slide (.ppt)
X

Author's Preferred Treatment for Type IV Monteggia Fracture-Dislocations

As with any Monteggia lesion, treatment is primarily aimed at obtaining and maintaining reduction of the radial head, either by an open or closed technique. Percutaneous intramedullary fixation is frequently necessary because of inherent fracture instability. Following open treatment, the elbow is immobilized in a long-arm cast for 4 to 6 weeks in 110 to 120 degrees of flexion with the forearm in neutral rotation. A short-arm cast is used thereafter if additional fracture protection is necessary. Home rehabilitation is performed until restoration of motion and strength. Final radiographs are obtained with full restoration of motion and strength to be certain there is anatomic reduction of the proximal radioulnar and radiocapitellar joints. 

Treatment Principles for Monteggia Equivalent Lesions

As with the true Bado types, treatment focuses on two general components of the lesion: Ulnar fracture alignment and radial head reduction. Associated injuries must be dealt with appropriately, and are discussed thoroughly in other sections of this chapter and book. 

Management of Expected Adverse Outcomes and Unexpected Complications in Monteggia Fracture-Dislocations

Chronic Monteggia Fracture-dislocations

A late presenting, previously undetected dislocation of the radial head is not as uncommon as we all would prefer (Table 14-8).32,34,38,43,50,51,73,100,102,127,142 Isolated radial head dislocations with remote trauma have been mistaken for congenital radial head dislocations.87 The shape of the ulna in patients with a seemingly isolated dislocation of the radial head usually indicates persistent plastic deformation or malunion of the ulna and a traumatic etiology to the radial head dislocation (Figs. 14-3 and 14-39).83,90,127,138 Chronic Monteggia lesions have been diagnosed as early as several weeks after injury follow-up for a misdiagnosed, isolated ulnar fracture; or years later because of pain, restriction of motion, or extremity malalignment. Even a few weeks after injury, treatment becomes much more complicated than acute recognition and intervention. Proper recognition of a dislocated radial head at the time of injury can prevent the difficult problem of an untreated, chronic Monteggia lesion. 
 
Table 14-8
Monteggia Fracture-dislocations
View Large
Table 14-8
Monteggia Fracture-dislocations
Common Adverse Outcomes and Complications
Chronic Monteggia lesion
Acute radial nerve palsy or posterior interosseous nerve palsy
Tardy radial nerve palsy
Acute ulnar nerve palsy
Acute anterior interosseous nerve palsy
Myositis ossificans
Compartment syndrome
X
Figure 14-39
Chronic Monteggia lesion with ulnar bow line.
 
A: The injury radiograph of an 8-year-old girl who fell, spraining her arm. Note the anterior bow of the ulna (black arrows) and loss of the radiocapitellar relation (open arrow). The diagnosis of a Monteggia lesion was not established. B: Radiograph at time of late diagnosis. Note the persistent ulnar bow and overgrowth of radius.
A: The injury radiograph of an 8-year-old girl who fell, spraining her arm. Note the anterior bow of the ulna (black arrows) and loss of the radiocapitellar relation (open arrow). The diagnosis of a Monteggia lesion was not established. B: Radiograph at time of late diagnosis. Note the persistent ulnar bow and overgrowth of radius.
View Original | Slide (.ppt)
Figure 14-39
Chronic Monteggia lesion with ulnar bow line.
A: The injury radiograph of an 8-year-old girl who fell, spraining her arm. Note the anterior bow of the ulna (black arrows) and loss of the radiocapitellar relation (open arrow). The diagnosis of a Monteggia lesion was not established. B: Radiograph at time of late diagnosis. Note the persistent ulnar bow and overgrowth of radius.
A: The injury radiograph of an 8-year-old girl who fell, spraining her arm. Note the anterior bow of the ulna (black arrows) and loss of the radiocapitellar relation (open arrow). The diagnosis of a Monteggia lesion was not established. B: Radiograph at time of late diagnosis. Note the persistent ulnar bow and overgrowth of radius.
View Original | Slide (.ppt)
X
When a previously undetected proximal radioulnar and radiocapitellar dislocation is encountered (Fig. 14-40), there is controversy regarding subsequent care. At present there are limited levels of evidence and conflicting retrospective literature on this problem. Some reports indicate that the natural history of the untreated lesion is not problematic.96,124,136 Fahey44 suggested that although persistent dislocations do well in the short-term, problems arise over time resulting in substantial patient morbidity. Other reports support the view that the natural history of persistent dislocation is not benign and is associated with restricted motion, deformity, functional impairment, pain, potential degenerative arthritis, and late neuropathy.1,6,15,18,26,50,53,63,64,66,67,83 Kalamchi66 reported pain, progressive valgus deformity, and restricted motion, especially loss of forearm rotation and elbow flexion. Tardy nerve palsies have been reported subsequent to long-standing, unrecognized Monteggia lesions.1,6,61,84 
Figure 14-40
Chronic Monteggia lesion with a persistent anterior radial head dislocation and ossification of the displaced annular ligament.
Flynn-ch014-image040.png
View Original | Slide (.ppt)
X

Indications for Treatment

Treatment indications have ranged from offering all patients with chronic Monteggia lesions surgical correction to limiting intervention to patients with pain, restricted motion, and functional disability. That wide spectrum of expert opinions makes individual case decisions difficult for patients, parents, and clinicians. Blount19 and Fowles et al.48 suggested that reconstruction provides the best results in patients who have had a dislocation for 3 to 6 months or less. Fowles et al.48 reported successful relocations up to 3 years after injury; Freedman et al.50 up to 6 years after injury. Throughout the literature, the appropriate age for radial head reduction seems to be younger than 10 years.137 Hirayama et al.60 suggested that the reduction of a chronically dislocated radial head should be avoided if there is significant deformation of the radiocapitellar joint architecture including permanent irregularity of the radial head or flattening of the capitellum. Seel and Peterson125 suggested that the age of the patient and the duration of the dislocation are unimportant. Their criteria for surgical repair were (i) normal concave radial head articular surface and (ii) normal shape and contour of the ulna and radius (deformity of either correctable by osteotomy). They treated seven patients ranging in age from 5 to 13 years for chronic dislocations that had been present from 3 months to 7 years. All seven were fully active with no elbow pain or instability at an average of 4 years after surgery. 
Although they recommended surgical treatment of chronic Monteggia lesions in children because of the long-term sequelae, Rodgers et al.121 cautioned that the results of reconstructive procedures can be unpredictable and associated with a number of complications including malunion of the ulnar shaft, recurrent radiocapitellar subluxation, and radial and ulnar neuropathy. 
At present, most authors advocate surgical reconstruction of a chronic Monteggia when (i) the diagnosis is made early, (ii) there is preservation of the normal concave radial head and convex capitellum, (iii) especially when there is progressive deformity (i.e., valgus), loss of motion and pain, and (iv) the patient and family are well aware of the concerns with operative reconstruction. 

Surgical Reconstruction

Descriptions of surgical reconstruction for pediatric chronic Monteggia lesions have been variable in terms of (i) annular ligament repair or reconstruction,57 (ii) ulnar osteotomy alone65,75 or in combination with ligament reconstruction,34,62,94 and (iii) radial osteotomy.33 The technique for delayed reduction of the radial head in a Monteggia fracture-dislocation is attributed to Bell-Tawse,14 who used the surgical approach described by Boyd (Fig. 14-31).20 Other surgical approaches have been developed.56,139 Nakamura et al.94 reported long-term clinical and radiographic outcomes in patients undergoing ulnar osteotomy with annular ligament reconstruction. At a mean follow-up of seven years, they reported excellent results in 19 out of 22 patients. Of concern, the radial head remained subluxated in five patients at the time of latest follow-up. Radiographic results did deteriorate when surgical reconstruction was performed more than 3 years after injury or in patients above 12 years of age. 

Annular Ligament Repair or Reconstruction

Most but not all authors advocate surgical repair or reconstruction of the annular ligament in conjunction with an ulnar osteotomy for a pediatric chronic Monteggia lesion.34,62,94,121 Annular ligament repair or reconstruction without an osteotomy is very rarely indicated.24 Kalamchi66 restored stability after open reduction and osteotomy by utilizing the native annular ligament. The native ligament is generally present, even years later. The central opening can be dilated with a probe and/or surgical hemostat or by radial incisions. The annular ligament is then brought back over the radial head and down to its anatomic location on the neck before repair to the proximal ulna periosteum. Bell-Tawse14 used a strip of triceps tendon to reconstruct the annular ligament, as did Lloyd-Roberts84 and Hurst.64 Bell-Tawse14 used the central portion of the triceps tendon passed through a drill hole in the ulna and around the radial neck to stabilize the reduction and immobilized the elbow in a long-arm cast in extension (Fig. 14-41). Bucknill23 and Lloyd-Roberts84 modified the Bell-Tawse procedure by using the lateral portion of the triceps tendon, with a transcapitellar pin for stability. The elbow was immobilized in flexion. Hurst and Dubrow64 used the central portion of the triceps tendon but carried the dissection of the periosteum distally along the ulna to the level of the radial neck, which provided more stable fixation rather than stopping dissection at the olecranon as described by Bell-Tawse.14 They also used a periosteal tunnel rather than a drill hole for fixation of the tendinous strip to the ulna. Other authors have used other soft tissues for reconstruction, including the lacertus fibrosus,29 a strip of the forearm fascia (Fig. 14-31),130 palmaris longus-free tendon graft,157 and free fascia lata graft.150 
Figure 14-41
Bell-Tawse reconstruction.
 
The central slip of the triceps is used to reconstruct an annular ligament in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow).
The central slip of the triceps is used to reconstruct an annular ligament in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow).
View Original | Slide (.ppt)
Figure 14-41
Bell-Tawse reconstruction.
The central slip of the triceps is used to reconstruct an annular ligament in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow).
The central slip of the triceps is used to reconstruct an annular ligament in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow).
View Original | Slide (.ppt)
X
Seel and Peterson125 described the use of two holes drilled in the proximal ulna. The holes are placed at the original attachments of the annular ligament and allow repair of the annular ligament (frequently avulsed from one attachment and trapped within the joint) or reconstruction of the annular ligament with triceps tendon. This technique secures the radial head in its normal position from any dislocated position and allows osteotomy for correction of any accompanying deformity of the ulna or radius. Seel and Peterson125 noted that the Bell-Tawse procedure tends to pull the radius posterolaterally (Fig. 14-42). A tight annular ligament reconstruction may constrict the neck of the radius, potentially limiting the growth of the radial neck (“notching”) and reducing forearm rotation. Seel and Peterson125 placed a single drill hole obliquely across the ulna to exit medially at the site of the medial attachment of the annular ligament on the coronoid process of the ulna (Fig. 14-42). The tendon was routed through the tunnel, brought around the neck, and sutured to the lateral side of the ulna. With this construct, the direction of stability was posteromedial. The use of two drill holes to secure the annular ligament or other reconstructive tendon at both normal attachments of the annular ligament on the ulna achieved a more normal posteromedial holding force on the neck of the radius. Alternatives to holes drilled in the bone are small bone staples or bone-anchoring devices. 
Figure 14-42
Drawings of transverse cuts of the proximal right radius and ulna (viewed distally) at the level of the radial head.
 
Left: Route of the triceps tendon in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow). Center: Drill hole placed obliquely to exit the ulna at the site of the medial annular ligament attachment. The direction of stability is posteromedial (large arrow). Right: Two drill holes exit the ulna at sites of medial and lateral annular ligament attachments. The direction of stability is anatomic (arrow).
Left: Route of the triceps tendon in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow). Center: Drill hole placed obliquely to exit the ulna at the site of the medial annular ligament attachment. The direction of stability is posteromedial (large arrow). Right: Two drill holes exit the ulna at sites of medial and lateral annular ligament attachments. The direction of stability is anatomic (arrow).
View Original | Slide (.ppt)
Figure 14-42
Drawings of transverse cuts of the proximal right radius and ulna (viewed distally) at the level of the radial head.
Left: Route of the triceps tendon in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow). Center: Drill hole placed obliquely to exit the ulna at the site of the medial annular ligament attachment. The direction of stability is posteromedial (large arrow). Right: Two drill holes exit the ulna at sites of medial and lateral annular ligament attachments. The direction of stability is anatomic (arrow).
Left: Route of the triceps tendon in Bell-Tawse reconstruction. The direction of stability is posterior (large arrow). Center: Drill hole placed obliquely to exit the ulna at the site of the medial annular ligament attachment. The direction of stability is posteromedial (large arrow). Right: Two drill holes exit the ulna at sites of medial and lateral annular ligament attachments. The direction of stability is anatomic (arrow).
View Original | Slide (.ppt)
X

Ulnar Osteotomy

All surgeons advocate an ulnar osteotomy, with or without ligament repair or reconstruction, for a chronic pediatric Monteggia lesion. Various types of osteotomies have been used to facilitate reduction of the radial head and prevent recurrent subluxation (Fig. 14-43). Kalamchi66 reported using a “drill hole” ulnar osteotomy to obtain reduction of the radial head in two patients. Minimal periosteal stripping with this technique allowed the osteotomy to heal rapidly. Hirayama et al.60 used a 1-cm distraction ulnar osteotomy approximately 5 cm distal to the tip of the olecranon with plate and screw fixation, but complications with loosening and plate breakage occurred. Mehta88,89 used an osteotomy of the proximal ulna stabilized with bone graft. In neither series was annular ligament repair performed. 
Figure 14-43
 
A: Diagram of floating open ulnar osteotomy without fixation or bone graft. B: Similar ulnar osteotomy with radiocapitellar pin fixation. C: Unfortunately in this case, the radial head was never reduced and the pin was placed without anatomic alignment. D: In this situation, the osteotomy was plated without bone graft, the radiocapitellar joint pinned anatomically for 4 weeks. E: Long-term follow-up with anatomic healing.
A: Diagram of floating open ulnar osteotomy without fixation or bone graft. B: Similar ulnar osteotomy with radiocapitellar pin fixation. C: Unfortunately in this case, the radial head was never reduced and the pin was placed without anatomic alignment. D: In this situation, the osteotomy was plated without bone graft, the radiocapitellar joint pinned anatomically for 4 weeks. E: Long-term follow-up with anatomic healing.
View Original | Slide (.ppt)
Figure 14-43
A: Diagram of floating open ulnar osteotomy without fixation or bone graft. B: Similar ulnar osteotomy with radiocapitellar pin fixation. C: Unfortunately in this case, the radial head was never reduced and the pin was placed without anatomic alignment. D: In this situation, the osteotomy was plated without bone graft, the radiocapitellar joint pinned anatomically for 4 weeks. E: Long-term follow-up with anatomic healing.
A: Diagram of floating open ulnar osteotomy without fixation or bone graft. B: Similar ulnar osteotomy with radiocapitellar pin fixation. C: Unfortunately in this case, the radial head was never reduced and the pin was placed without anatomic alignment. D: In this situation, the osteotomy was plated without bone graft, the radiocapitellar joint pinned anatomically for 4 weeks. E: Long-term follow-up with anatomic healing.
View Original | Slide (.ppt)
X
Inoue and Shionoya65 compared the results of simple corrective ulnar osteotomy in six patients with those of posterior angular (overcorrected) osteotomy in six others, and found that better clinical outcomes were obtained with the overcorrected, angular osteotomy. Tajima and Yoshizu,143 in a series of 23 neglected Monteggia fractures, found that the best results were obtained by opening wedge osteotomy of the proximal ulna without ligament reconstruction. 
Exner43 reported that in patients with chronic dislocation of the radial head after missed type I Monteggia lesions, reduction was successfully obtained with ulnar corticotomy and gradual lengthening and angulation of the ulna using an external fixator. Another option for chronic type IV Monteggia lesion is a shortening osteotomy of the radius, usually indicated for angulation of the radius without angulation of the ulna. 

Author's Preferred Treatment

In patients younger than 12 years of age with delayed diagnosis of a Monteggia lesion, reduction and stabilization of the radial head to its anatomic relationship with the capitellum is indicated if the radial head is still concave centrally. Even though the child may do well in the short-term without reduction of the radial head, problems usually develop in adolescence or adulthood when progressive instability, pain, weakness of the forearm, and restriction of motion are likely. There is also a risk of tardy radial or ulnar nerve palsies. The concavity of the radial head and convexity of the capitellum are assessed preoperatively, usually by MRI scan. Appropriate discussion with the patient and family regarding the risks and complications of surgery is performed. This is not an operation for the inexperienced surgeon or uninformed patient and family. 
We perform an ulnar osteotomy and open reduction of the radial capitellar and radioulnar joints with annular ligament reconstruction. The surgical approach is extensile (Fig. 14-44). The skin incision is curvilinear to allow for proximal triceps tendon harvesting, if necessary, and distally for an ulnar opening wedge osteotomy. Initially, only the proximal portion is opened. The radial nerve is identified between the brachialis and brachioradialis in the distal humerus. Dissection of the nerve is performed distally to its motor (posterior interosseous nerve) and sensory branches (Fig. 14-22). Generally, the posterior interosseous nerve is adherent to the dislocated radial head. The nerves are mobilized and protected throughout the remainder of the reconstruction. 
Figure 14-44
Author's preferred technique for chronic Monteggia reconstruction.
 
A: Clinical deformity of chronic Monteggia lesion with increased cubitus valgus. B: Extensile incision for annular ligament reconstruction and ulnar osteotomy. C: Exposure of radiocapitellar and radioulnar joint with elevation of extensor–supinator origin from lateral epicondyle, protection of radial nerve, and thorough joint debridement. D: Radial head with osteochondral change from chronic dislocation. Annular ligament has been reduced around radial neck and sutures are in place for construction to annular ligament. E: Ulnar opening wedge osteotomy at site of maximum deformity. F: Long-term follow-up of ulnar osteotomy and the anatomic reduction of proximal radioulnar joint and radiocapitellar joint.
A: Clinical deformity of chronic Monteggia lesion with increased cubitus valgus. B: Extensile incision for annular ligament reconstruction and ulnar osteotomy. C: Exposure of radiocapitellar and radioulnar joint with elevation of extensor–supinator origin from lateral epicondyle, protection of radial nerve, and thorough joint debridement. D: Radial head with osteochondral change from chronic dislocation. Annular ligament has been reduced around radial neck and sutures are in place for construction to annular ligament. E: Ulnar opening wedge osteotomy at site of maximum deformity. F: Long-term follow-up of ulnar osteotomy and the anatomic reduction of proximal radioulnar joint and radiocapitellar joint.
View Original | Slide (.ppt)
Figure 14-44
Author's preferred technique for chronic Monteggia reconstruction.
A: Clinical deformity of chronic Monteggia lesion with increased cubitus valgus. B: Extensile incision for annular ligament reconstruction and ulnar osteotomy. C: Exposure of radiocapitellar and radioulnar joint with elevation of extensor–supinator origin from lateral epicondyle, protection of radial nerve, and thorough joint debridement. D: Radial head with osteochondral change from chronic dislocation. Annular ligament has been reduced around radial neck and sutures are in place for construction to annular ligament. E: Ulnar opening wedge osteotomy at site of maximum deformity. F: Long-term follow-up of ulnar osteotomy and the anatomic reduction of proximal radioulnar joint and radiocapitellar joint.
A: Clinical deformity of chronic Monteggia lesion with increased cubitus valgus. B: Extensile incision for annular ligament reconstruction and ulnar osteotomy. C: Exposure of radiocapitellar and radioulnar joint with elevation of extensor–supinator origin from lateral epicondyle, protection of radial nerve, and thorough joint debridement. D: Radial head with osteochondral change from chronic dislocation. Annular ligament has been reduced around radial neck and sutures are in place for construction to annular ligament. E: Ulnar opening wedge osteotomy at site of maximum deformity. F: Long-term follow-up of ulnar osteotomy and the anatomic reduction of proximal radioulnar joint and radiocapitellar joint.
View Original | Slide (.ppt)
X
Next, the anconeus–extensor carpi ulnaris (Kocher) interval is utilized to expose the joint. The joint exposure is carried proximal with elevation of the extensor–supinator mass and capsule as a single tissue plane off the distal humerus. This gives complete exposure of the elbow joint. The radial head is usually dislocated anteriorly and superiorly with a wall of interposed capsule and ligament blocking reduction. Pulvinar and synovitis are thoroughly debrided from the elbow joint. Particular attention is paid to a thorough debridement of the proximal radioulnar joint to allow the radial head to fit anatomically into place once reduced. At this stage, a decision needs to be made if the native annular ligament can be used for reconstruction. There is usually a central perforation in the capsular wall that separates the dislocated radial head from the joint. This perforation indicates the site of the opening of the original ligament. Dilatation and radial incisions extending from the center outward are made to enlarge this opening. This usually enables the native annular ligament to be reduced over the radial neck. Capsular adhesions are removed from the radial head to assist in reduction of the radial head and neck back into the joint. The native ligament usually detaches from the ulna with a large periosteal sleeve (the site of ossification on the radiographs of a chronic Monteggia lesion (Fig. 14-40)), and this can be the site for suture reattachment to the ulna of the native ligament. If the native ligament cannot be used, and most of the time it can, then it is thoroughly debrided in preparation for harvesting of triceps fascia for ligament reconstruction. 
A radial head reduction is then attempted. The reduction is scrutinized for congruity between the radial head and the capitellum. If this is satisfactory, ligamentous repair or reconstruction alone can be done. This is exceedingly unusual. If the radius cannot be reduced, an ulnar osteotomy is made at the site of maximal deformity. This involves a more distal exposure to the ulna. Subperiosteal dissection is performed with fluoroscopic assistance at the site of maximal deformity. An opening wedge osteotomy is made with a laminar spreader to allow the radial head to align itself with the capitellum without pressure. Partial overcorrection of the ulnar alignment is the goal. A clever way to do this is to anatomically pin the radiocapitellar joint and allow the ulnar osteotomy to open the necessary amount for this reduction. When reduced anatomically, the ulnar osteotomy is then fixed partially proximally and distally with a plate and screws. Further testing of a complete stable arc of rotation of the radial head is performed in order to be certain that the correct level and degree of osteotomy were obtained to maintain radiocapitellar and radioulnar alignment. If a temporary radiocapitellar pin was used, it is removed for this testing. If correct, the fixation is completed. No bone graft is used, and the periosteum is repaired. 
At this stage, the annular ligament repair or reconstruction is completed. If the native ligament is used, and it usually is in situations that are a year or less out from injury, then Ethibond mattress sutures (Ethicon, Somerville, NJ) are placed in the annular ligament and the ligament is repaired through ulnar periosteal tunnels. None of the radial sutures are tightened until all are placed. If reconstruction is necessary, a 6- to 8-cm strip of triceps fascia is developed from proximal to distal, carefully elevating the periosteum from the proximal ulna down to the level of the radial neck. Over the olecranon apophysis, this dissection will be delicate so as not to inadvertently amputate the fascia. The strip of tendon is then passed through the periosteum, around the radial neck, and then brought back and sutured to itself and the ulnar periosteum. The passage and securing in the periosteum is similar in design to the drill holes advocated by Seel and Peterson.125 At this stage, the radial head and capitellum alignment should be anatomic throughout full rotation. Final closure involves repair of the capsule and extensor–supinator origin back to the lateral epicondylar region of the humerus. Final radiographs and fluoroscopic testing of a stable arc of motion in both flexion–extension and pronation–supination planes are gently tested before completion of closure. Prophylactic volar and dorsal forearm fasciotomies are carefully performed through the original incision with elevation of the skin and subcutaneous tissues and a long tenotomy scissors. Final inspection of the radial nerve is performed before subcutaneous and skin closure. 
Radiocapitellar or radioulnar pin fixation is rarely needed if the osteotomy and soft tissue repair tension are correct. As mentioned at times, pin fixation is used intraoperatively for temporary stability to get the corrective ulnar osteotomy right; it is then removed to test the range of motion. If there is radial head deformity in very chronic reconstructions, pinning the joint is sometimes useful for 3 to 4 weeks postoperatively. In my experience, this has been occasionally necessary in repeat surgery for a chronic Monteggia lesion in which options are limited and the patient has pain and marked limitation of motion. Then, the radiocapitellar joint is secured by passing a smooth, transcapitellar pin through the posterior aspect of the capitellum into the radial head and neck with the elbow at 90 degrees and the forearm in supination. A pin of sufficient size is mandatory to avoid pin failure71; a small pin may fatigue and break. An alternative technique to secure the reduction of the radius is transversely pinning the radius to the ulna.81 
After wound closure, a bivalved long-arm cast is applied with the forearm in 60 to 90 degrees of supination and the elbow flexed 80 to 90 degrees. The cast is maintained for 4 to 6 weeks and is then changed to a removable bivalved cast to allow active motion, especially pronation and supination. Elbow flexion and extension return more rapidly than rotary motion of the forearm which may take up to 6 months to improve, with pronation possibly limited, though minimally, permanently.120 Final desired result is not determined until radiographs are anatomic with full restoration of motion. 

Nerve Injuries

Radial Nerve

The literature reflects a 10% to 20% incidence of radial nerve injury, making it the most common complication associated with Monteggia fractures (Table 14-8).63 It is most commonly associated with types I and III injuries.14,96,127 The posterior interosseous nerve is most commonly injured because of its proximity to the radial head and its intimate relation to the Arcade of Frohse (Fig. 14-22). The arcade may be thinner and therefore more pliable in children than in adults.132 In addition, the periosteum is much thicker in pediatric patients. This may account in part for the rapid resolution of the nerve injury in children. A radial nerve injury in a child is treated expectantly. Nerve function usually returns by 12 weeks after reduction, if not sooner.133,135 A review of a series of pediatric Monteggia lesions98 recommends waiting 6 months before intervention for a posterior interosseous nerve injury. Most series report 100% resolution in both fractures treated promptly and those treated late.1,6,82 
Two reports92,130 of irreducible Monteggia fractures caused by interposition of the radial nerve posterior to the radial head documented return of function approximately 4 months after the nerve was replaced to its normal anatomic position and the radial head was reduced. Morris,92 in cadaver studies, showed that significant anterior dislocation of the radial head and varus angulation of the elbow allowed the radial nerve to slide posterior to the radial head and, with subsequent reduction of the radial head, become entrapped. If a chronic reconstruction is undertaken in the presence of a persistent radial nerve lesion, it is highly recommended that radial nerve exploration and decompression be performed before joint debridement. Rodgers et al.121 cited a partial nerve injury during similar circumstances that was then microscopically repaired with full recovery. Rang114 acknowledged the same experience in an open educational forum. 

Ulnar Nerve

Bryan22 reported one adult with an ulnar nerve lesion associated with a type II Monteggia lesion with spontaneous resolution. Stein et al.135 reported three combined radial and ulnar nerve injuries, two of which underwent exploration and decompression for functional return of the nerve. 

Median Nerve

Median nerve injuries are uncommon with Monteggia fractures, but injury to the anterior interosseous nerve has been reported.157,160 Stein et al.,135 in their report specifically examining nerve injuries in Monteggia lesions, reported no median nerve deficits. Watson and Singer157 reported entrapment of the main trunk of the median nerve in a greenstick ulnar fracture in a 6-year-old girl. Completion of the fracture was necessary for release of the nerve. At 6 months after surgery, there was full motor recovery but the sensation was slightly reduced in the tips of the index finger and thumb. 

Tardy Radial Nerve Palsy

Tardy radial nerve palsy associated with radial head dislocation has been infrequently reported.1,6,61,82,164 Although reported treatment has varied, excision of the radial head with exploration and neurolysis of the nerve generally produced good results,1,6 whereas exploration of the nerve alone produced variable results.61,82 Yamamoto et al.164 combined radial head resection and nerve exploration with tendon transfers, producing good results in two patients. 

Periarticular Ossification

Two patterns of ossification after Monteggia fracture-dislocations have been noted radiographically: Ossification around the radial head and myositis ossificans. Ossification around the radial head and neck14,63,82,84,136,138 appears as a thin ridge of bone in a cap-like distribution and may be accompanied by other areas resembling sesamoid bones (Table 14-8). This typically resorbs with time. Ossification may also occur in the area of the annular ligament,40 including in a chronic Monteggia with a displaced annular ligament (Fig. 14-40). Elbow function generally is not affected by the formation of these lesions14,63,84,136,138 as long as the radial head and neck are anatomically reduced. 
The other form of ossification is true myositis ossificans, reported to occur in approximately 3% of elbow injuries and 7% of Monteggia lesions in adults and children.97,149 Myositis ossificans has a good prognosis in patients younger than 15 years of age, appearing at 3 to 4 weeks after injury and resolving in 6 to 8 months. Its occurrence is related to the severity of the initial injury, association with a fractured radial head, the number of remanipulations during treatment, and passive motion of the elbow during the postoperative period.97,149 

Summary, Controversies, and Future Directions Related to Monteggia Fracture-Dislocations

Adherence to several fundamental principles helps ensure a good outcome after Monteggia fracture-dislocations in children: 
  1.  
    With a high index of suspicion and careful radiographic evaluation, acute Monteggia injuries can be accurately diagnosed. Evaluation of radiocapitellar alignment requires an AP and true lateral view of the elbow. All forearm fractures require careful inspection of the proximal radioulnar joint and the radiocapitellar joint before treatment.
  2.  
    The radiocapitellar line must be anatomic in all views.
  3.  
    If the radial head is dislocated, always look for ulnar fracture or plastic deformation. Conversely, if the ulna is fractured or plastically deformed, always look for a radial head subluxation or dislocation.
  4.  
    Stability of the ulnar reduction is required to maintain reduction of the radial head. Stability may be inherent to the fracture pattern (plastic deformation or incomplete fractures) or achieved by internal fixation (intramedullary fixation for short oblique and transverse fractures; plate and screw fixation for long oblique and comminuted fractures).
  5.  
    Radial head reduction confirmed by an intact radiocapitellar line must be achieved by open or closed means.
  6.  
    If the radial head is irreducible or unstable, removal of interposed soft tissue is required. An annular ligament repair or reconstruction may be required.
  7.  
    Treatment of an acute Monteggia lesion is more straightforward and much more successful than reconstruction of a chronic Monteggia lesion.
  8.  
    Reconstruction of a chronic Monteggia lesion is not an operation for the uninitiated. There is a high risk of recurrent or residual radial head subluxation and iatrogenic nerve injury.
Refining treatment recommendations for acute and chronic Monteggia lesions in the future will require prospective multicenter, scientific inquiry. To date, there are no prospective investigations with a large number of pediatric patients and sufficient duration of follow-up. The vast majority of published studies report limited outcomes data. Studies that report functional outcomes in addition to union rates, motion, and pain scores will permit surgeons to accurately counsel and monitor patient recovery and progress. 

Acknowledgment

The authors wish to recognize contributions of the authors of previous editions of this chapter, Drs. Earl Stanley and Jose de la Garza. 

References

1.
Adams JR, Rizzoli HV. Tardy radial and ulnar nerve palsy: A case report. J Neurosurg. 1959; 16:342–344.
2.
Agarwal A. Type IV Monteggia fracture in a child. Can J Surg. 2008; 51(2):E44–E45.
3.
Almquist EE, Gordon LH, Blue AI. Congenital dislocation of the head of the radius. J Bone Joint Surg Am. 1969; 51:1118–1127.
4.
Anderson HJ. Monteggia fractures. Adv Orthop Surg. 1989; 4:201–204.
5.
Arazi M, Ogun TC, Kapicioglu MI. The Monteggia lesion and ipsilateral supracondylar humerus and distal radius fractures. J Orthop Trauma. 1999; 13(1):60–63.
6.
Austin R. Tardy palsy of the radial nerve from a Monteggia fracture. Injury. 1976; 7(3):202–204.
7.
Babb A, Carlson WO. Monteggia fractures: Beware! S D J Med. 2005; 58(7):283–285.
8.
Bado JL. La lesion de Monteggia. Intermedica Sarandi. 1958;328.
9.
Bado JL. The Monteggia Lesion. Springfield, IL: Charles C Thomas; 1962.
10.
Bado JL. The Monteggia lesion. Clin Orthop Relat Res. 1967; 50:71–86.
11.
Basmajian JV, Griffen WR Jr. Function of anconeus muscle: An electromyographic study. J Bone Joint Surg Am. 1972; 54:1712–1714.
12.
Beaty JH. Fractures and dislocations about the elbow in children: Section on Monteggia fractures. AAOS Instr Course Lect. 1991; 40:373–384.
13.
Beddow FH, Corkery PH. Lateral dislocation of the radio-humeral joint with greenstick fracture of the upper end of the ulna. J Bone Joint Surg Br. 1960; 42:782–784.
14.
Bell Tawse AJ. The treatment of malunited anterior Monteggia fractures in children. J Bone Joint Surg Br. 1965; 47:718–723.
15.
Best TN. Management of old unreduced Monteggia fracture dislocations of the elbow in children. J Pediatr Orthop. 1994; 14:193–199.
16.
Bhandari N, Jindal P. Monteggia lesion in a child: Variant of a Bado type-IV lesion. A case report. J Bone Joint Surg Am. 1996; 78(8):1252–1255.
17.
Biyani A. Ipsilateral Monteggia equivalent injury and distal radial and ulnar fracture in a child. J Orthop Trauma. 1994; 8(5):431–433.
18.
Blasier D, Trussell A. Ipsilateral radial head dislocation and distal fractures of both forearm bones in a child. Am J Orthop. 1995; 24:498–500.
19.
Blount WP. Fractures in Children. Baltimore, MD: Williams & Wilkins; 1955.
20.
Boyd HB. Surgical exposure of the ulna and proximal one third of the radius through one incision. Surg Gynecol Obstet. 1940; 71:86–88.
21.
Boyd HB, Boals JC. The Monteggia lesion: A review of 159 cases. Clin Orthop Relat Res. 1969; 66:94–100.
22.
Bryan RS. Monteggia fracture of the forearm. J Trauma. 1971; 11:992–998.
23.
Bucknill TM. Anterior dislocation of the radial head in children. Proc R Soc Med. 1977; 70(9):620–624.
24.
Cappellino A, Wolfe SW, Marsh JS. Use of a modified Bell Tawse procedure for chronic acquired dislocation of the radial head. J Pediatr Orthop. 1998; 18(3):410–414.
25.
Captier G, Canovas F, Mercier N, et al. Biometry of the radial head: Biomechanical implications in pronation and supination. Surg Radiol Anat. 2002; 24(5):295–301.
26.
Caravias DE. Some observations on congenital dislocation of the head of the radius. J Bone Joint Surg Br. 1957; 39:86–90.
27.
Castillo Odena I [Milch H, transl]. Bipolar fracture-dislocation of the forearm. J Bone Joint Surg Am. 1952; 34:968–976.
28.
Cheung EV, Yao J. Monteggia fracture-dislocation associated with proximal and distal radioulnar joint instability: A case report. J Bone Joint Surg Am. 2009; 91(4):950–954.
29.
Corbett CH. Anterior dislocation of the radius and its recurrence. Br J Surg. 1931; 19:155.
30.
Curry GJ. Monteggia fracture. Am J Surg. 1947; 123:613–617.
31.
Dattani R, Patnaik S, Kantak A, et al. Distal humerus lateral condyle fracture and Monteggia lesions in a 3-year old child: A case report. Acta Orthop Belg. 2008; 74(4):542–545.
32.
David-West KS, Wilson NI, Sherlock DA, et al. Missed Monteggia injuries. Injury. 2005; 36(10):1206–1209.
33.
De Boeck H. Radial neck osteolysis after annular ligament reconstruction. A case report. Clin Orthop Relat Res. 1997; 342:94–98.
34.
Degreef I, De Smet L. Missed radial head dislocations in children associated with ulnar deformation: Treatment by open reduction and ulnar osteotomy. J Orthop Trauma. 2004; 18(6):375–378.
35.
Denucé P. Memoire sun les luxations du coude. Paris: These de Paris; 1854.
36.
Deshpande S, O'Doherty D. Type I Monteggia fracture dislocation associated with ipsilateral distal radial epiphyseal injury. J Orthop Trauma. 2001; 15(5):373–375.
37.
Devnani AS. Missed Monteggia fracture dislocation in children. Injury. 1997; 28(2):131–133.
38.
Dormans JP, Rang M. The problem of Monteggia fracture-dislocations in children. Orthop Clin North Am. 1990; 21:251–256.
39.
Eady JL. Acute Monteggia lesions in children. JSC Med Assoc. 1975; 71:107–112.
40.
Earwaker J. Posttraumatic calcification of the annular ligament of the radius. Skeletal Radiol. 1992; 21:149–154.
41.
Edwards EG. The posterior Monteggia fracture. Am Surg. 1952; 18:323–337.
42.
Evans M. Pronation injuries of the forearm. J Bone Joint Surg Br. 1949; 31:578–588.
43.
Exner GU. Missed chronic anterior Monteggia lesion. Closed reduction by gradual lengthening and angulation of the ulna. J Bone Joint Surg Br. 2001; 83(4):547–550.
44.
Fahey JJ. Fractures of the elbow in children: Monteggia's fracture-dislocation. AAOS Instr Course Lect. 1960; 17:39.
45.
Fahmy NRM. Unusual Monteggia lesions in kids. Injury. 1980; 12:399–404.
46.
Faundez AA, Ceroni D, Kaelin A. An unusual Monteggia type-I equivalent fracture in a child. J Bone Joint Surg Br. 2003; 85(4):584–586.
47.
Fernandez FF, Egenolf M, Carsten C, et al. Unstable diaphyseal fractures of both bones of the forearm in children: Plate fixation versus intramedullary nailing. Injury. 2005; 36(10):1210–1216.
48.
Fowles JV, Sliman N, Kassah MT. The Monteggia lesion in children. Fracture of the ulna and dislocation of the radial head. J Bone Joint Surg Am. 1983; 65:1276–1282.
49.
Frazier JL, Buschmann WR, Insler HP. Monteggia type I equivalent lesion: Diaphyseal ulna and proximal radius fracture with a posterior elbow dislocation in a child. J Orthop Trauma. 1991; 5:373–375.
50.
Freedman L, Luk K, Leong JC. Radial head reduction after a missed Monteggia fracture: Brief report. J Bone Joint Surg Br. 1988; 70:846–847.
51.
Gibson WK, Timperlake RW. Orthopedic treatment of a type IV Monteggia fracture-dislocations in a child. J Bone Joint Surg Br. 1992; 74:780–781.
52.
Giustra PE, Killoran PJ, Furman RS, et al. The missed Monteggia fracture. Radiology. 1974; 110(1):45–47.
53.
Givon U, Pritsch M, Levy O, et al. Monteggia and equivalent lesions: A study of 41 cases. Clin Orthop Relat Res. 1997; 337:208–215.
54.
Givon U, Pritsch M, Yosepovich A. Monteggia lesion in a child: Variant of a Bado type-IV lesion. A case report. J Bone Joint Surg Am. 1997; 79(11):1753–1754.
55.
Gleeson AP, Beattie TF. Monteggia fracture-dislocation in children. J Accid Emerg Med. 1994; 11(3):192–194.
56.
Gorden ML. Monteggia fracture: A combined surgical approach employing a single lateral incision. Clin Orthop Relat Res. 1967; 50:87–93.
57.
Gyr BM, Stevens PM, Smith JT. Chronic Monteggia fractures in children: Outcome after treatment with the Bell-Tawse procedure. J Pediatr Orthop B. 2004; 13(6):402–406.
58.
Haddad ES, Manktelow AR, Sarkar JS. The posterior Monteggia: A pathological lesion? Injury. 1996; 27:101–102.
59.
Henry AK. Extensile Exposure. Baltimore, MD: Williams & Wilkins; 1970.
60.
Hirayama T, Takemitsu Y, Yagihara K, et al. Operation for chronic dislocation of the radial head in children. J Bone Joint Surg Br. 1987; 69:639–642.
61.
Holst-Nielson F, Jensen V. Tardy posterior interosseus nerve palsy as a result of an unreduced radial head dislocation in Monteggia fractures: A report of two cases. J Hand Surg Am. 1984; 9:572–575.
62.
Hui JH, Sulaiman AR, Lee HC, et al. Open reduction and annular ligament reconstruction with fascia of the forearm in chronic monteggia lesions in children. J Pediatr Orthop. 2005; 25(4):501–506.
63.
Hume AC. Anterior dislocation of the head of the radius associated with undisplaced fracture of olecranon in children. J Bone Joint Surg Br. 1957; 39:508–512.
64.
Hurst LC, Dubrow EN. Surgical treatment of symptomatic chronic radial head dislocation: A neglected Monteggia fracture. J Pediatr Orthop. 1983; 3:227–230.
65.
Inoue G, Shionoya K. Corrective ulnar osteotomy for malunited anterior Monteggia lesions in children. 12 patients followed for 1 to 12 years. Acta Orthop Scand. 1998; 69:73–76.
66.
Kalamchi A. Monteggia fracture-dislocation in children. J Bone Joint Surg Am. 1986; 68:615–619.
67.
Kaplan EB. The quadrate ligament of the radio-ulnar joint in the elbow. Bull Hosp Joint Dis. 1964; 25:126–130.
68.
Karachalios T, Smith EJ, Pearse MF. Monteggia equivalent injury in a very young patient. Injury. 1992; 23:419–420.
69.
Kay RM, Skaggs DL. The pediatric Monteggia fracture. Am J Orthop. 1998; 27(9):606–609.
70.
Kemnitz S, De Schrijver F, De Smet L. Radial head dislocation with plastic deformation of the ulna in children. A rare and frequently missed condition. Acta Orthop Belg. 2000; 66(4):359–362.
71.
King RE. Treating the persistent symptomatic anterior radial head dislocation. J Pediatr Orthop. 1983; 3:623–624.
72.
Kloen P, Rubel IF, Farley TD, et al. Bilateral Monteggia fractures. Am J Orthop. 2003; 32(2):98–100.
73.
Koslowsky TC, Mader K, Wulke AP, et al. Operative treatment of chronic Monteggia lesion in younger children: A report of three cases. J Shoulder Elbow Surg. 2006; 15(1):119–121.
74.
Kristiansen B, Eriksen AF. Simultaneous type II Monteggia lesion and fracture separation of the lower radial epiphysis. Injury. 1986; 17:51–62.
75.
Ladermann A, Ceroni D, Lefevre Y, et al. Surgical treatment of missed Monteggia lesions in children. J Child Orthop. 2007; 1(4):237–242.
76.
Lambrinudi C. Intramedullary Kirschner wires in the treatment of fractures: (Section of Orthopaedics). Proc R Soc Med. 1940; 33:153–157.
77.
Landin LA. Fracture patterns in children. Acta Paediatr Scand Suppl. 1983; 54:192.
78.
Lascombes P, Prevot J, Ligen JN, et al. Elastic stable intramedullary nailing in forearm shaft fractures in children: 85 cases. J Pediatr Orthop. 1990; 10:167–171.
79.
Leonidou A, Pagkalos J, Lepetsos P, et al. Pediatric Monteggia fractures: A single-center study of the management of 40 patients. J Pediatr Orthop. 2012; 32(4):352–356.
80.
Letta C, Schmied M, Haller A, et al. Combined Monteggia and Galeazzi lesions of the forearm: A rare injury. Unfallchirurg. 2012; 115(11):1034–1037.
81.
Letts M, Locht R, Wiens J. Monteggia fracture-dislocations in children. J Bone Joint Surg Br. 1985; 67:724–727.
82.
Lichter RL, Jacksen T. Tardy palsy of posterior interosseous nerve with Monteggia fracture. J Bone Joint Surg Am. 1975; 57:124–125.
83.
Lincoln TL, Mubarak SJ. “Isolated” traumatic radial-head dislocation. J Pediatr Orthop. 1994; 14:454–457.
84.
Lloyd-Roberts GC, Bucknill TM. Anterior dislocation of the radial head in children: Aetiology, natural history, and management. J Bone Joint Surg Br. 1977; 59:402–407.
85.
Luhmann SJ, Gordon JE, Schoenecker PL. Intramedullary fixation of unstable both-bone forearm fractures in children. J Pediatr Orthop. 1998; 18(4):451–456.
86.
Maeda H, Yoshida K, Doi R, et al. Combined Monteggia and Galeazzi fractures in a child: A case report and review of the literature. J Orthop Trauma. 2003; 17(2):128–131.
87.
McFarland B. Congenital dislocation of the head of the radius. Br J Surg. 1936; 24:41–49.
88.
Mehta SD. Flexion osteotomy of ulna for untreated Monteggia fracture in children. Indian J Surg. 1985; 47:15–19.
89.
Mehta SD. Missed Monteggia fracture. J Bone Joint Surg Br. 1993; 75:337.
90.
Miles KA, Finlay DB. Disruption of the radiocapitellar line in the normal elbow. Injury. 1989; 20:365–367.
91.
Monteggia GB. Instituzioni Chirurgiche. Milan: Maspero; 1814.
92.
Morris AH. Irreducible Monteggia lesion with radial nerve entrapment. J Bone Joint Surg Am. 1974; 56:1744–1746.
93.
Mullick S. The lateral Monteggia fracture. J Bone Joint Surg Am. 1977; 57:543–545.
94.
Nakamura K, Hirachi K, Uchiyama S, et al. Long-term clinical and radiographic outcomes after open reduction for missed Monteggia fracture-dislocations in children. J Bone Joint Surg Am. 2009; 91(6):1394–1404.
95.
Nakashima H, Kondo K, Saka K. Type II Monteggia lesion with fracture-separation of the distal physis of the radius. Am J Orthop. 2000; 29(9):717–719.
96.
Naylor A. Monteggia fractures. Br J Surg. 1942; 29:323.
97.
Neviaser RJ, LeFevre GW. Irreducible isolated dislocation of the radial head: A case report. Clin Orthop Relat Res. 1971; 80:72–74.
98.
Olney BW, Menelaus MB. Monteggia and equivalent lesions in childhood. J Pediatr Orthop. 1989; 9:219–223.
99.
Oner FC, Diepstraten AF. Treatment of chronic posttraumatic dislocation of the radial head in children. J Bone Joint Surg Br. 1993; 75:577–581.
100.
Osamura N, Ikeda K, Hagiwara N, et al. Posterior interosseous nerve injury complicating ulnar osteotomy for a missed Monteggia fracture. Scand J Plast Reconstr Surg Hand Surg. 2004; 38(6):376–378.
101.
Ovesen O, Brok KE, Arreskov J, et al. Monteggia lesions in children and adults: An analysis of etiology and long-term results of treatment. Orthopedics. 1990; 13(5):529–534.
102.
Papandrea R, Waters PM. Posttraumatic reconstruction of the elbow in the pediatric patient. Clin Orthop Relat Res. 2000;(370):115–126.
103.
Papavasilou VA, Nenopoulos SP. Monteggia-type elbow fracture in childhood. Clin Orthop Relat Res. 1988; 233:230–233.
104.
Parsch KD. Die Morote-Drahtung bei proximalen und mittleren Unterarm Schaft Frakturen des Kindes. Operat Orthop Traumatol. 1990; 2:245–255.
105.
Pavel A, Pitman JM, Lance EM, et al. The posterior Monteggia fracture: A clinical study. J Trauma. 1965; 5:185–199.
106.
Peiró A, Andres F, Fernandez-Esteve F. Acute Monteggia lesions in children. J Bone Joint Surg Am. 1977; 59:92–97.
107.
Peltier LF. Eponymic fractures: Giovanni Battista Monteggia and Monteggia's fracture. Surgery. 1957; 42:585–591.
108.
Penrose JH. The Monteggia fracture with posterior dislocation of the radial head. J Bone Joint Surg Br. 1951; 33:65–73.
109.
Pérez Sicialia JE, Morote Jurado JL, Corbach Girones JM, et al. Osteosintesis percuntanea en fracturas diafisaris de ante brazo en ninos y adolescentes. Rev Esp Cir Ost. 1977; 12:321–334.
110.
Powell RS, Bowe JA. Ipsilateral supracondylar humerus fracture and Monteggia lesion: A case report. J Orthop Trauma. 2002; 16(10):737–740.
111.
Price CT, Scott DS, Kurener ME, et al. Malunited forearm fracture in children. J Pediatr Orthop. 1990; 10:705–712.
112.
Pugh DM, Galpin RD, Carey TP. Intramedullary Steinmann pin fixation of forearm fractures in children. Long-term results. Clin Orthop Relat Res. 2000;(376):39–48.
113.
Ramsey RH, Pedersen HE. The Monteggia fracture-dislocation in children. Study of 15 cases of ulnar-shaft fracture with radial-head involvement. JAMA. 1962; 82:1091–1093.
114.
Rang M. The Story of Orthopaedics. Philadelphia, PA: Saunders; 2000.
115.
Ravessoud FA. Lateral condyle fracture and ipsilateral ulnar shaft fracture: Monteggia equivalent lesions. J Pediatr Orthop. 1985; 5:364–366.
116.
Reckling F. Unstable fracture-dislocations of the forearm (Monteggia and Galeazzi lesions). J Bone Joint Surg Am. 1982; 64:857–863.
117.
Reckling FW, Cordell LD. Unstable fracture-dislocations of the forearm. The Monteggia and Galeazzi lesions. Arch Surg. 1968; 96:999–1007.
118.
Ring D, Jupiter JB, Waters PM. Monteggia fractures in children and adults. J Am Acad Orthop Surg. 1998; 6(4):215–224.
119.
Ring D, Waters PM. Operative fixation of Monteggia fractures in children. J Bone Joint Surg Br. 1996; 78:734–739.
120.
Rodgers WB, Smith BG. A type IV Monteggia injury with a distal diaphyseal radius fracture in a child. J Orthop Trauma. 1993; 7:84–86.
121.
Rodgers WB, Waters PM, Hall JE. Chronic Monteggia lesions in children: Complications and results of reconstruction. J Bone Joint Surg Am. 1996; 78:1322–1329.
122.
Rodríguez-Merchán EC. Pediatric fractures of the forearm. Clin Orthop Relat Res. 2005;(432):65–72.
123.
Ruchelsman DE, Klugman JA, Madan SS, et al. Anterior dislocation of the radial head with fractures of the olecranon and radial neck in a young child: A Monteggia equivalent fracture-dislocation variant. J Orthop Trauma. 2005; 19(6):425–428.
124.
Salter RB, Zaltz C. Anatomic investigations of the mechanism of injury and pathologic anatomy of “pulled elbow” in young children. Clin Orthop Relat Res. 1971; 77:134–143.
125.
Seel MJ, Peterson HA. Management of chronic posttraumatic radial head dislocation in children. J Pediatr Orthop. 1999; 19:306–312.
126.
Singh AP, Dhammi IK, Jain AK, et al. Monteggia fracture dislocation equivalents: Analysis of eighteen cases treated by open reduction and internal fixation. Chin J Traumatol. 2011; 14(4):221–226.
127.
Smith FM. Monteggia fractures: An analysis of 25 consecutive fresh injuries. Surg Gynecol Obstet. 1947; 85:630–640.
128.
Smith MV, Calfee RP, Baumgarten KM, et al. Upper extremity-specific measures of disability and outcomes in orthopaedic surgery. J Bone Joint Surg Am. 2012; 94(3):277–285.
129.
Sood A, Khan O, Bagga T. Simultaneous monteggia type I fracture equivalent with ipsilateral fracture of the distal radius and ulna in a child: A case report. J Med Case Reports. 2008; 2:190.
130.
Spar I. A neurologic complication following Monteggia fracture. Clin Orthop Relat Res. 1977; 122:207–209.
131.
Speed JS, Boyd HB. Treatment of fractures of ulna with dislocation of head of radius: Monteggia fracture. JAMA. 1940; 125:1699.
132.
Spinner M. The arcade of Frohse and its relationship to posterior interosseous nerve paralysis. J Bone Joint Surg Br. 1968; 50:809–812.
133.
Spinner M, Freundlich BD, Teicher J. Posterior interosseous nerve palsy as a complication of Monteggia fracture in children. Clin Orthop Relat Res. 1968; 58:141–145.
134.
Spinner M, Kaplan EB. The quadrate ligament of the elbow—its relationship to the stability of the proximal radioulnar joint. Acta Orthop Scand. 1970; 41:632–647.
135.
Stein F, Grabias SL, Deffer PA. Nerve injuries complicating Monteggia lesions. J Bone Joint Surg Am. 1971; 53:1432–1436.
136.
Stelling FH, Cote RH. Traumatic dislocation of head of radius in children. JAMA. 1956; 160:732–736.
137.
Stoll TM, Willis RB, Paterson DC. Treatment of the missed Monteggia fracture in the child. J Bone Joint Surg Br. 1992; 74:436–440.
138.
Storen G. Traumatic dislocation of radial head as an isolated lesion in children. Acta Chir Scand. 1958–1959; 116:144–147.
139.
Strachen JCH, Ellis BW. Vulnerability of the posterior interosseous nerve during radial head reduction. J Bone Joint Surg Br. 1971; 53:320–332.
140.
Strong ML, Kopp M, Gillespie R. Fracture of the radial neck and proximal ulna with medial displacement of the radial shaft. Orthopedics. 1989; 12:1577–1579.
141.
Sur YJ, Park JB, Song SW. Pediatric posterior Monteggia lesion: A greenstick fracture of the proximal ulnar metaphysis with radial neck fracture: A case report. J Orthop Trauma. 2010; 24(2):e12–e16.
142.
Tait G, Sulaiman SK. Isolated dislocation of the radial head: A report of two cases. Injury. 1988; 19:125–126.
143.
Tajima T, Yoshizu T. Treatment of long-standing dislocation of the radial head in neglected Monteggia fractures. J Hand Surg Am. 1995; 20:S91–S94.
144.
Tan JW, Mu MZ, Liao GJ, et al. Pathology of the annular ligament in paediatric Monteggia fractures. Injury. 2008; 39(4):451–455.
145.
Thakore HK. Lateral Monteggia fracture in children (case report). Ital J Orthop Traumatol. 1983; 9(1):55–56.
146.
Theodorou SD. Dislocation of the head of the radius associated with fracture of the upper end of ulna in children. J Bone Joint Surg Br. 1969; 51:700–706.
147.
Theodorou SD, Ierodiaconou MD, Rousis N. Fracture of the upper end of the ulna associated with dislocation of the head of the radius in children. Clin Orthop Relat Res. 1988; 228:240–249.
148.
Thompson GH, Wilber JH, Marcus RE. Internal fixation of fractures in children and adolescents. Clin Orthop Relat Res. 1984; 188:10–20.
149.
Thompson HC III, Garcia A. Myositis ossificans: Aftermath of elbow injuries. Clin Orthop Relat Res. 1967; 50:129–134.
150.
Thompson JD, Lipscomb AB. Recurrent radial head subluxation treated with annular ligament reconstruction. Clin Orthop Relat Res. 1989; 246:131–135.
151.
Tompkins DG. The anterior Monteggia fracture. J Bone Joint Surg Am. 1971; 53:1109–1114.
152.
Tubbs RS, O'Neil JT, Key CD, et al. The oblique cord of the forearm in man. Clin Anat. 2007; 20(4):411–415.
153.
Tubbs RS, Shoja MM, Khaki AA, et al. The morphology and function of the quadrate ligament. Folia Morphol (Warsz). 2006; 65(3):225–227.
154.
Verstreken L, Delronge G, Lamoureux J. Shaft forearm fractures in children: Intramedullary nailing with immediate motion: A preliminary report. J Pediatr Orthop. 1988; 8:450–453.
155.
Walker JL, Rang M. Forearm fractures in children. Cast treatment with the elbow extended. J Bone Joint Surg Br. 1991; 73:299–301.
156.
Waters PM, Bae DS. Pediatric Hand and Upper Limb Surgery: A Practical Guide. Philadelphia, PA: Lippincott Williams & Wilkins; 2012:351–365.
157.
Watson JA, Singer GC. Irreducible Monteggia fracture: Beware nerve entrapment. Injury. 1994; 25:325–327.
158.
Watson-Jones R. Fractures and Joint Injuries. 3rd ed. Baltimore, MD: Williams & Wilkins; 1943.
159.
Werner FW, Taormina JL, Sutton LG, et al. Structural properties of 6 forearm ligaments. J Hand Surg Am. 2011; 36(12):1981–1987.
160.
Wiley JJ, Galey JP. Monteggia injuries in children. J Bone Joint Surg Br. 1985; 67:728–731.
161.
Wilkins KE. Changes in the management of monteggia fractures. J Pediatr Orthop. 2002; 22(4):548–554.
162.
Wise RA. Lateral dislocation of the head of radius with fracture of the ulna. J Bone Joint Surg. 1941; 23:379.
163.
Wright PR. Greenstick fracture of the upper end of the ulna with dislocation of the radio-humeral joint or displacement of the superior radial epiphysis. J Bone Joint Surg Br. 1963; 45:727–731.
164.
Yamamoto K, Yoshiaki Y, Tomihara M. Posterior interosseous nerve palsy as a complication of Monteggia fractures. Nippon Geka Hokan. 1977; 46:46–56.