A thirty-three-year-old female driver was involved in a motor vehicle collision. Initial trauma evaluation revealed a 10-cm transverse laceration over the right Achilles tendon as well as absent right foot plantar sensation and an absent posterior tibial artery pulse. Radiographs demonstrated a Hawkins type-III fracture dislocation of the talar neck (Figs. 1-A and 1-B). Parenteral antibiotics were administered, the wound was irrigated and debrided, and the injured ankle was splinted after a failed attempt at closed reduction in the Emergency Department. The patient was then taken urgently to the operating room.
The talar body was found to be dislocated from both the tibiotalar and subtalar joints; it was lodged in a subcutaneous position in the posteromedial hindfoot and visible through the medial extent of the posterior laceration. The talar neck was moderately comminuted with dorsomedial impaction. The talar body, devoid of all soft-tissue attachments (including the deltoid ligaments), was carefully reduced back into the tibiotalar and subtalar joints through the open wound and an accessory medial incision between the tibialis anterior and tibialis posterior tendons. The FDL tendon was found to be avulsed proximally at its musculotendinous junction (Fig. 2-A), and it was shortened and tenodesed to the flexor hallucis longus (FHL) tendon with the foothold in a plantigrade position. The posterior tibial artery was found to be transected, while the tibial nerve and the Achilles tendon were both intact (Fig. 2-B). The posterior tibial artery was ligated after Doppler ultrasound confirmation of collateral arterial supply via the dorsalis pedis artery. Given the extent of the soft-tissue injury, staged internal fixation was planned. Two 0.062-inch Kirschner wires were advanced across the talar neck fracture to maintain reduction (Fig. 3). A medially based spanning external fixator was assembled and applied with apex pins in the midshaft of the tibia, the calcaneal tuberosity, and the first metatarsal neck.
Immediately postoperatively, the patient was non-weight-bearing on the right lower extremity. Sensation on the plantar surface of the right foot remained decreased, and only a flicker of toe flexion and extension was observed. The patient was returned to the operating room for definitive fixation of the talar neck fracture two weeks after the injury.
The calcaneal posterior facet and the tibiotalar and talonavicular articular surfaces were visualized through extension of the previous anteromedial incision. The talar neck fracture was anatomically reduced with use of anteromedial and lateral incisions. A 2.4-mm minifragment plate was applied to the lateral recess and talar neck, and a 4.0-mm fully threaded cortical screw was placed from the talar head into the body to secure the medial column. The external fixator was maintained because of persistent tibiotalar subluxation, which was evident intraoperatively.
Postoperatively, the patient was non-weight-bearing on the right lower extremity with the external fixator in place for six weeks. During this period, active toe extension and passive toe flexion exercises were initiated with physical therapy. The skin of the posteromedial ankle became necrotic and required multiple surgical debridements (Fig. 4). This skin defect ultimately required the use of a vacuum-assisted closure device and application of a skin graft.
A computerized tomographic scan eight weeks after fracture fixation demonstrated a loose osteochondral fragment in the subtalar joint, delayed union of the talar neck fracture, and signs of osteonecrosis of the talar body. The patient was returned to the operating room where the subtalar joint was visualized through the previous anterolateral incision. The joint was irrigated and the osteochondral fragment was removed. At this time, a bone graft from the proximal part of the tibia was harvested and impacted into a crevice in the anterolateral and dorsal neck regions of the talus. The wounds were thoroughly irrigated, and the anterolateral incision was closed in a single layer. Subsequently, the patient remained non-weight-bearing on the right lower extremity. She had no subsequent postoperative complications.
At approximately sixteen weeks after injury, plain radiographs showed evidence of union of the talar neck fracture and osteonecrosis of the talar body, but no evidence of collapse of the talar dome (Figs. 5-A and 5-B). The patient had full toe flexor strength, no pain, improved plantar sensation, and healed wounds. She was allowed to begin partial weight-bearing.