Session V - Foot and Ankle

Operative Management of Talar Neck Fractures: Outcomes and the Effect of Timing

Heather A. Vallier, MD; Sean E. Nork, MD; David P. Barei, MD; Stephen K. Benirschke, MD; Bruce J. Sangeorzan, MD; Harborview Medical Center, Seattle, Washington, USA

Purpose: Talar neck fractures are typically the result of high-energy trauma and are frequently associated with osteonecrosis and posttraumatic peri-talar arthritis. Because of the poor blood supply to the talus, these injuries are frequently treated urgently to preserve any remaining blood supply. We evaluated the incidence of osteonecrosis and posttraumatic arthritis after fixation of these fractures, the impact of surgical delay on results, and the functional outcomes after talar neck fractures.

Methods: Over a 67-month period, 100 consecutive patients with 102 talar neck fractures (OTA classification 72-A1) were treated surgically at a level-1 trauma center. Sixty men and forty women with an average age of 32.6 years (range, 13 to 77) and an average Injury Severity Score of 15.8 (range, 9 to 50) were identified. The fractures were divided into groups (Hawkins' classification as modified by Canale and Kelly): type I (N = 4), type II (N = 68), type III (N = 25), and type IV (N = 5). Twenty-four fractures were open. Twenty-three patients had contiguous talar body fractures, and 20 had associated lateral process fractures. All fractures were treated with open reduction and rigid internal fixation by using small fragment or mini-fragment implants or both. Dual anteromedial and anterolateral surgical approaches were used in 91 patients. Complications, secondary procedures, and the radiographic presence of osteonecrosis and posttraumatic arthritis were determined. Foot Function Index (FFI) and Musculoskeletal Functional Assessment (MFA) questionnaires were administered and the results tabulated.

Results: Sixty fractures were evaluated at an average of 35.7 months >from injury (range, 12 to 74). Fixation was performed within the first 24 hours in 40 patients (67%). Delayed presentation and associated life-threatening injuries precluded urgent operative management in the remaining 20 patients. The average time from injury to fixation was 3.7 days (range, 4 hours to 48 days). Radiographic evidence of osteonecrosis was identified in 53% of patients. However, 37% of these patients demonstrated revascularization of the talar dome radiographically without collapse. Osteonecrosis was seen in 39% of Hawkins II fractures, with 56% of these progressing to collapse of the talar dome. In Hawkins III fractures, 64% developed osteonecrosis, and 67% of these progressed to collapse. Chi square analysis of fixation within 6 hours, 8 hours, 12 hours, or 24 hours, determined no correlation between surgical delay and the development of osteonecrosis. Time was also analyzed as a continuum using a Student's t-test, and no correlation was seen between the time to fixation and the development of osteonecrosis. The mean time to fixation for patients who developed osteonecrosis was 3.4 days (range, 4 hours to 20 days) compared with 5.0 days (range, 4 hours to 48 days) for patients who did not develop osteonecrosis. Further analysis of all cases with fixation within 24 hours revealed a 50% incidence of osteonecrosis; the mean time to fixation for both patients with and without osteonecrosis was 13 hours. Osteonecrosis was associated with comminution of the talar neck (58% incidence, P<0.03) and with open fractures (69% incidence, P<0.05). Fifty-four percent of patients developed posttraumatic arthritis of the tibiotalar or subtalar joints or both. Posttraumatic arthritis occurred more frequently after comminuted talar neck fractures (61% incidence, P<0.07) or after open fractures (69% incidence, P = 0.09). Patients with comminuted fractures or open injuries also had lower functional outcome scores on the FFI and MFA.

Discussion and Conclusions: The impact of surgical delay on the outcome of talar neck fractures is unknown. It has been suggested that early operative intervention protects the already tenuous blood supply to the posterior portion of the talus after a fracture of the talar neck. Although the numbers in this series are small, no correlation was found between surgical delay and the development of osteonecrosis. Osteonecrosis and posttraumatic arthritis were associated with talar neck comminution and open fractures, confirming that higher-energy injuries have more complications and a worse prognosis. This finding is further strengthened by the poor FFI and MFA scores among patients with comminuted fractures or open injuries. We continue to recommend expeditious fracture fixation, with urgent management of open injuries and reduction of dislocations. Proceeding with definitive fixation in this setting, whenever possible, will provide rigid fracture stability and may promote early revascularization of fracture fragments.