Combined ORIF and Subtalar Arthrodesis Technique for Talar Neck Fracture Dislocations

Abstract

Category: Trauma; Hindfoot Introduction/Purpose: Talar neck fracture-dislocations are uncommon but potentially devastating given the critical role the talus plays in lower extremity biomechanics. Open reduction internal fixation of this injury pattern is associated with high rates of post- operative complications. Arthrodesis of the subtalar joint during the index surgery for these fractures offers several hypothetical advantages including increased stability and enhanced osseous blood supply to the talus as well as improved foot alignment and reduction quality of the talar neck. Additionally, given the high rates of subsequent subtalar arthritis in this population, fusion in the acute setting may decrease the risk for future surgery. We describe a technique for combined talar neck fixation and subtalar arthrodesis and report on early outcomes for a series of patients treated with this method. Methods: Patients with Hawkins grade III-IV talar neck fracture-dislocations underwent single-stage operative fixation of the talus and subtalar joint arthrodesis. The talus was approached through anterolateral and anteromedial incisions. Care was taken to preserve intact soft-tissue attachments, especially near the tarsal canal and the dorsal aspect of the talar neck. After initial debridement, the subtalar joint was primed for arthrodesis, limiting preparation to the posterior facet. The talar body was then reduced to the calcaneus and preliminarily pinned creating a stable platform for the subsequent reduction of the talar head and neck. Following provisional fixation and confirmation of hindfoot alignment utilizing direct visualization and Harris heel radiograph, a cannulated screw was placed across the subtalar joint. The talar neck reduction was then refined and secured with a lateral plate. Fixation of the medial neck to prevent medial column shortening was accomplished with a second plate or screws depending on fracture morphology. Results: Six patients with talar neck fracture-dislocations were treated by a single orthopedic foot and ankle surgeon. Follow-up ranged from 6-13 months, short-term clinical and radiographic results were noted. Five patients reported mild or no pain and all patients had returned to their activities of daily living including work. Radiographic evidence of avascular necrosis developed in one case with a Hawkins grade IV fracture-dislocation. All but one patient healed their subtalar arthrodesis and no patient experienced loss of reduction. Notably, radiographic signs of arthritis at an adjacent joint developed in three cases but patients were asymptomatic. No revision surgeries were required although one patient with an open fracture did develop an infection resulting in a return to the operating room for irrigation and debridement. Conclusion: Augmenting operative fixation of the talar neck with subtalar arthrodesis provides additional stability and reliable maintenance of alignment. In a small series, preparation of the subtalar joint did not confer an increased risk of avascular necrosis compared to historically reported rates for high-grade talar neck fracture-dislocations. The combined technique produced favorable clinical outcomes and potentially reduces the need for future operations given the high frequency of post-traumatic subtalar arthritis and symptomatic deformity in patients with subtalar fracture-dislocations.