Injuries of the Midfoot
Tarsal Navicular Fractures
Author’s Preferred Treatment
Tarsometatarsal (Lisfranc Joint) Injuries
Injuries of the Forefoot
First Metatarsal Fractures
Central Metatarsal Fractures
Fifth Metatarsal Fractures
Fractures of the Toes
High-Energy Injuries: “The Multiple Injured Foot”
Bony and Soft Tissue Reconstruction
Compartment Syndrome of the Foot
Anatomic and Pathophysiologic Considerations
Stable, nondisplaced navicular fractures are treated primarily conservatively with immobilization in a walking cast for 6 to 8 weeks. If there is any doubt regarding instability the patient is examined under fluoroscopy or standing-weight–bearing radiographs are performed. The dynamic examination under fluoroscopy is in our hands a very helpful and precise diagnostic tool to guide treatment and give accurate information about the stability of each column of the traumatized foot. When the indication for operative treatment has been confirmed, the final decision for operative intervention is left to the discretion of the patient. In a detailed dialogue, treatment options are outlined and common risks and complications are described.
At surgery, the patient is positioned in the supine position on a translucent table. The leg can be placed on a triangular cushion to create a plantigrade foot position when using the C-arm (Fig. 62-10).
The foot is exsanguinated and a tourniquet is applied. The first step is always a comprehensive clinical and radiographic reevaluation of the stability of the medial and lateral columns and the adjacent joints. Avulsion fractures of the dorsal navicular should be fixed if an articular step-off is identified, and articular incongruity of more than 2 mm is present. An avulsion fracture of the medial tuberosity is also fixed if displaced, as ongoing pull of the tibialis posterior tendon can provoke further displacement. In this case reduction with a pointed reduction clamp is followed by 2.7-mm screw fixation supported with a washer. Most often this can be achieved using a percutaneous technique.
When opting for an open approach to fix a navicular fracture, the skin incision is centered straight over the navicular and lateral to the tibialis anterior tendon. The dissection is performed with the tendon of the extensor hallucis longus identified and the neurovascular bundle retracted. A distractor or medial external spanning fixator can be mounted from the talar neck to the cuneiforms to increase visibility and indirectly reduce fragments by ligamentotaxis. The optimal Schanz pin placement is determined during surgery and usually includes placement of a proximal pin medially into the talar neck perpendicular to the talar axis. The second pin is bicortically anchored perpendicular to the long axis in the base of the first metatarsal. Pin placement is not recommended in the medial malleolar bone as the bony area for fixation is small and the spanning direction is not optimal. If the lateral column shows signs of instability as well, a lateral column fixator is introduced spanning from the calcaneal tuberosity to the base of the fifth metatarsal.
When exposing the fracture site we usually try to maintain the soft tissue attachments to large fracture fragments if possible to preserve blood supply. After debridement, the large fragments are addressed first. A pointed reduction clamp can be used to directly reduce the major fragment which is fixed using 2.7-mm low-profile screws. Typically, two screws are required to control rotation and increase fixation stability. In some cases reduction is tricky and impossible by direct means. In this case, one or two 1.25-mm K-wires can be placed into the body of the fragment to serve as joysticks. With the fragment directed into its original position, temporary K-wire fixation is performed, followed by screw fixation. To avoid prominence of the screw heads and to prevent cortical avulsion when introducing the head of the screw in an inclined fashion we prefer to create a trough by countersinking the head of the screw.
A two-fragment fracture may be treated percutaneously with screw fixation. However, the talo-navicular joint requires anatomic reduction to decrease the risk of secondary osteoarthritis. If there remains any doubt about achieving an optimal reduction, opt for open reduction and internal fixation. In the case of comminuted fractures, we usually start by identifying the largest fragment. After anatomic reduction and provisional K-wire fixation of this piece, smaller fragments are reduced onto it. The adjacent articular surfaces of the talar head and cuneiforms can serve as templates for joint reconstruction. The comminuted navicular fracture usually requires more stable support, hence, autologous bone grafting into the zone of impaction is recommended to restore its body, increase stability, and support healing. Following reduction and bone grafting, a 2.0- or 2.4-mm longitudinal plate is molded along the dorsal surface of the navicular body and secured with converging or crossing screws. Beware of the lateral corner of the tarsal navicular, as this is often insufficiently addressed. The lateral corner is difficult to visualize as it turns downward to articulate with the cuboid. To prevent shortening, and thus increase the risk of abduction deformity resulting in longitudinal arch collapse, this corner requires proper restoration. If small fragments cannot be sufficiently reduced bridge plate osteosynthesis is an option. A 2.7-mm reconstruction plate, a semi-tubular plate, or a 3.5-mm small-fragment plate is placed anteromedially or straight dorsally to bridge from the talar head to a cuneiform or metatarsal (Fig. 62-11).
As an alternative, one can also perform bridging screw osteosynthesis into the cuneiforms. Although the primary goal is stability within the tarsal complex and the columns of the foot, respectively, temporary transfixation of essential joints should be avoided so as not to compromise their mobility. It is paramount to avoid screw placement from the navicular into the cuboid which would interfere with the mobile interplay between the medial and lateral columns of the foot. Elimination of motion at the naviculo-cuneiform joints increases stability within the medial tarsal complex and can be performed at any time without interfering with the functional results. If confronted with severely destroyed articular surfaces or nonreconstructable comminution, primary fusion remains as a salvage procedure. We usually stabilize the medial column with a 2.7-mm reconstruction plate to obtain optimal stability. However, the goal of fusion should be restoration of axial alignment and the length of the medial column, as well as stability while avoiding medial-to-lateral column fixation.
When treating navicular fractures always be aware of associated foot injuries and check for fractures of the cuboid, the anterior process of the calcaneus, and the talar head/neck, as well as subtalar injuries. In complex ligamentous foot injuries we typically start with reconstruction and stable fixation of the medial column. However, in severe crush injuries of the medial column, when there are major large fragments in the lateral column, it might be easier to start with reconstruction of the lateral column to restore overall foot length and to have a template for medial column alignment. After osteosynthesis has been accomplished, transfixing K-wires can be removed. However, if gross instability remains involving the essential joints, temporary K-wire transfixation can be left in situ for 6 weeks until capsulo-ligamentous healing has occurred. Before removing the medial column distraction device, we usually reevaluate stability of the medial and lateral columns and the adjacent joints under fluoroscopy. The connecting bar(s) can be removed with the Schanz pins being left in place and ab-/adduction and in-/eversion stress maneuvers can be performed. If the medial column remains unstable the fixator is left in situ for an additional 6 weeks (Fig. 62-12).
Stable, nondisplaced cuboid fractures and avulsion fractures without instability or associated injuries to the forefoot or midfoot are treated primarily conservatively with immobilization in a walking cast for 6 to 8 weeks. Dynamic fluoroscopy or standing weight-bearing radiographs are performed when there is concern regarding stability. The stability of each column always requires evaluation and determines the treatment algorithm. If operative treatment is indicated, risks and common complications need to be outlined to the patient and final decision is left to the discretion of the patient.
Over the years and with increasing understanding of the importance of the integrity of the longitudinal, as well as the transverse functional anatomy of the tarsal osseous complex, treatment strategies have shifted to a more aggressive approach. The goal is the restoration of articular congruence, column length, and capsulo-ligamentous stability. CT imaging and dynamic fluoroscopy will guide treatment. If the fracture is nondisplaced, but there is apparent ligamentous instability, a closed fixation technique is recommended using 1.6- or 2.0-mm K-wires introduced in a retrograde fashion from the base of the fourth and fifth metatarsals into the cuboid and the lateral cuneiform. Also temporary CC transfixation is optional. As an alternative, the lateral column can be spanned using an external fixator (Fig. 62-16).
Simple fractures in the coronal or longitudinal plane can be fixed using 2.7- or 3.5-mm screws. These are applied using a lag technique perpendicular to the fracture plane. However, screw fixation alone remains a rare treatment option, as the thin lateral cortex is prone to collapse. This technique should be performed only when good bone stock is present. In general, we prefer plate fixation as it provides a more stable construct, and thus, increased stability. Even with simple fracture patterns, open reduction is preferred over closed treatment as assessment and control of anatomic articular reconstruction via image intensification can be tricky due to the curvature of the articular surface. Closed reduction and internal screw fixation should be reserved for the patient with a compromised soft tissue envelope.
If associated injuries of the foot require surgical intervention, we recommend also addressing the minimally displaced cuboid fracture to increase midfoot stability. Especially with the severely damaged medial tarsal column, the cuboid will serve as the basis for reconstruction of medial column alignment. Articular surface displacement of more than 1 mm is, in our hands, an indication for operative fixation. An attempt should be made to reduce the cuboid by ligamentotaxis and application of a pointed reduction clamp. If reduction cannot be obtained or maintained, open reduction and fixation is required. All compression type fractures result in lateral column shortening, which will compromise patient satisfaction in the long run. These fractures require restoration of cuboid length, and, in most cases, an autologous bone graft is necessary to fill the defect.
Usually we place the patient in a supine position on a translucent fracture table using a bolster or wedge under the hip to rotate the injured leg into a neutral position. The leg is elevated and exsanguinated, and a tourniquet is inflated. The skin incision is centered straight over the cuboid and between the bases of the fourth and fifth metatarsals. The peroneal tendons and sural nerve are identified and protected. Usually, a mini-fragment fixator is placed along the lateral column to restore length, but also to increase visibility during articular reconstruction. We place one or two pins in the tuberosity of the calcaneus and an additional pin into the base of the fifth metatarsal. Articular compromise is addressed as necessary and with severely damaged surfaces the adjacent bone can be used as a template. Use a smooth lever to press the main fragments against the adjacent intact articular surface. Also, smooth K-wires can be used as joysticks to maneuver major segments into place. Bony defects should be filled with graft. Place the lateral cortex into its original position and buttress the lateral wall with a plate. Preformed mini-fragment plates with 2.0- or 2.7-mm screws can be used to secure bicortical fixation. If instability of the lateral column is obvious on dynamic examination we add internal spanning fixation. Internal spanning fixation can be applied proximally, distally, or both. We usually use 2.7-mm small-fragment reconstruction plates to bridge these joints. As discussed in navicular fracture treatment, screw placement from the cuboid into the navicular or the cuneiform complex should be avoided to prevent interfering with the mobile interplay between the medial and lateral columns of the foot. Primary fusion is only performed in the case of the most severe crush injuries when reconstruction is not possible at all. Most often, we opt for secondary fusion after initial reconstruction of the cuboid.
Cuboid dislocation can be regarded as a rarity, though it does occur in some severe TMT fracture–dislocations. In these cases, manual axial traction on the toes of the lateral column combined with slight pressure with the thumb will usually enable reduction. If closed reduction cannot be achieved, open reduction with direct visualization will be required bearing in mind that reduction can be obstructed by interposition of the peroneal tendons.91 In the severely crushed foot an associated compartment syndrome is a common finding and requires immediate intervention. In these cases open reduction should be performed to stabilize and anatomically restore the lateral column. We routinely transfix the lateral TMT complex with 1.25- or 1.6-mm K-wires that are left until ligamentous healing for 6 to 8 weeks (Fig. 62-17).
As we see a large number of high-energy injuries in our practice, high-injury severity and the presence of associated osseo-ligamentous injuries are common findings. Therefore, we favor an aggressive treatment regimen when confronted with cuneiform injuries. When a fracture is nondisplaced, ligamentous instability and the presence of associated foot injuries must be excluded. Only truly isolated injuries with a stable tarsus will be treated with cast immobilization for 6 weeks.
If closed reduction is required to restore the anatomy it is usually combined with percutaneous K-wire (1.6 to 2.0 mm), or preferably, 2.7-mm screw fixation to secure the construct (Fig. 62-21).
As in tarsal navicular and cuboid fracture treatment, associated osseous and ligamentous instability and deformity is best addressed using an open reduction technique with rigid fixation. A dorsal approach for the cuneiform is performed as in the treatment of medial TMT complex injuries. The neurovascular bundle is identified and protected during dissection to the cuneiform of interest. The tibialis anterior tendon is identified and freed if interposed. Column length and articular congruity are restored. In some cases a temporary spanning external fixator can be introduced into the base of the first metatarsal and the body of the talus or distal tibia to distract the medial column. If required for osseous reconstruction, autologous bone graft can be obtained from the calcaneus or distal tibia. The degree of joint damage should be carefully assessed. With high-injury severity, partial fusion is recommended. Screw and plate fixation can provide sufficient stability. When opting for plate fixation, 2.7-mm reconstruction or 1/3- to 1/4-tubular plates are usually used. To increase the stability of cuneiform fixation, screw positioning can include metatarso-cuneiform, intercuneiform, or naviculo-cuneiform transfixation, respectively. Typically, we start with intercuneiform transfixation in a medial to lateral direction using 2.7-mm cortical screws to create a stable medial tarsal block. We usually create a trough and countersink the head of the screw. This avoids prominence and prevents cortical avulsion when introducing the screw in an inclined fashion. Large fragments require screw fixation to the metatarsal base or navicular. Also, medial tarsal bridge plating as described above can be used to achieve and maintain medial column stability with good functional results.308 Cuneiform fractures usually require a higher amount of energy, thus, soft tissue injury and compromise are common findings. Be vigilant for an associated compartment syndrome, which needs to be addressed promptly. Following reduction and fixation, the patient is keep non-weight-bearing for 6 weeks following partial weight bearing for another 4 weeks.
Stable nondisplaced TMT injuries are treated conservatively with immobilization in a cast for 6 to 8 weeks. If there is any doubt regarding instability on the weight-bearing radiographs, dynamic imaging is performed.
For operative treatment, the patient is positioned in the supine position on a translucent table. The leg can be placed on a triangular cushion to achieve a plantigrade foot position when using the C-arm. We prefer to use two surgical approaches (dorso-medial and dorso-lateral) in complete TMT complex injuries. First the medial TMT complex is addressed. The cuneiforms are evaluated for intercuneiform instability, and, if unstable they are reduced using a pointed reduction clamp and intercuneiform fixation is performed (2.7-mm low-profile cortical screws, lag screw technique) in a medial-to-lateral direction. Two 2.7-mm screws provide sufficient stability to obtain a stable main tarsal body. Next, the second metatarsal is reduced back to its original position between the medial and lateral cuneiforms. Exact anatomic reduction of the base of the second metatarsal is secured with temporary K-wire fixation. We prefer an open reduction technique over an insufficient closed reduction because the improved visualization allows us to debride joints of obstructing capsulo-ligamentous tissue or osseous particles. Next, the “Lisfranc screw” is introduced from the proximal medial border of the medial cuneiform into the base of the second metatarsal. Following this a 2.7-mm cortical screw is inserted in a retrograde distal-to-proximal direction transfixing MT 2 and the intermediate cuneiform (Fig. 62-28).
The first TMT joint should be stabilized after other parts of the joint complex have been fixed. It is anatomically reduced using a reduction clamp or pointed forceps and temporary fixation is provided by 1.6- or 2-mm K-wires. Rotational deformity needs to be ruled out using standardized intraoperative simulated weight-bearing radiographic imaging to confirm restoration of both alignment and articular congruence. To obtain ideal fixation in some cases we inspect the first intermetatarsal space before fixing the first ray to the base of MT 2. Temporary fixation using 2-mm K-wires is followed by definite 2.7-mm cortical screw fixation. For all screws which start in the metatarsals, countersinking is mandatory to prevent cortical avulsion during screw compression. Usually we insert two crossing cortical screws using a lag screw technique starting with the distal-to-proximal screw and followed by proximal-to-distal screw placement. The TMT-3 joint is addressed next. After exact reduction, a distal-to-proximal 2.7-mm screw provides sufficient stability for TMT-3 fixation. As an alternative, a 5-hole 2.7-mm reconstruction plate can be placed on the dorsal surface of the joint complex to provide a more stable fixation construct. If the lateral TMT joint complex does not automatically reduce after restoration and rigid fixation of the medial TMT column complex, a closed reduction attempt can be performed. The fourth and fifth metatarsals usually perform as a single functional unit, and thus, reduction of one automatically reduces the second. However, in some circumstances capsulo-ligamentous tissue or bone fragments interfere with anatomic realignment, and hence, an open approach is required. TMT 4/5 can easily be accessed via a dorso-lateral approach. Usually fixation is carried out with converging K-wires. We prefer 2.0- over 1.6-mm K-wires to increase stability. If the fourth/fifth intermetatarsal interface is unstable a transverse intermetatarsal blocking screw can be introduced distal to the bases of the two metatarsals in a lateral-to-medial direction. Typically, a 3.5-mm mini-fragment cortical screw is used, but a 2.7-mm screw is an option.
In the case of comminution, we recommend bridge plating with a 2.7-mm reconstruction plate. The plate can be placed on the tarsal navicular or the talar head if talo-navicular instability has been identified. It should be remembered that the medial column bridging plate is meant to be a temporary immobilization device and not placed to create a permanent arthrodesis. The technical details of this method have been described in detail.308 With regard to comminution of the lateral TMT column complex, development of a pseudoarthrosis is preferred over arthrodesis. Complete TMT complex fusion is considered to be a salvage procedure. In these cases a staged fusion is sought, first of the medial TMT complex, and then second of the lateral TMT complex in case of persistent disability.
If comminution and instability of the medial TMT joint complex precludes anatomic reconstruction, we perform internal bridge plating which can be performed at each TMT joint of the medial complex. Internal spanning fixation of the lateral TMT complex is possible but necessitates removal of the bridging plate before the start of weight bearing. If medial column bridging has been performed the essential talo-navicular joint has to be freed up by plate shortening or removal in order to allow weight bearing to progress. Other implants within the rigid parts of the tarsal complex can remain in place if free of complications (Figs. 62-29 and 62-30).
An algorithm outlining the authors’ preferred treatment of first metatarsal fractures can be found in Figure 62-33.
An algorithm outlining the authors’ preferred treatment of central metatarsal fractures is presented in Figure 62-36.
An algorithm outlining the authors’ preferred treatment of fifth metatarsal fractures is presented in Figure 62-42.
Treatment of sesamoidal fractures should vary according to fracture type and location. Minimally displaced fractures are treated nonoperatively by local and systemic pain medication, icing, and initial immobilization in slight plantar flexion to relax the flexor hallucis brevis tendon followed by modification of foot wear. Sesamoidal fractures with only two large fragments can be fixed utilizing 2.0-mm screws. Dislocated fragments not treatable by screw fixation are usually removed by excision of the distal pole. Persistent painful nonunions and comminuted fractures of a single sesamoid are commonly treated by sesamoidectomy. The flexor hallucis brevis tendon is augmented when necessary to prevent deformity.
An algorithm outlining the authors’ preferred treatment for phalangeal fractures is presented in Figure 62-49.