Motion-Preserving Salvage for Failed Total Ankle Arthroplasty or Talar AVN: Outcomes of Combined Total Ankle Arthroplasty with Custom 3D-Printed Total Talus Replacement

BACKGROUND: Talar component collapse following total ankle arthroplasty (TAA) and talar avascular necrosis (AVN) with concurrent ankle arthritis represent challenging clinical scenarios. Traditional salvage with tibiotalocalcaneal arthrodesis sacrifices motion and has nonunion rates approaching 30%. This study evaluates outcomes of a motion-preserving salvage strategy: combined TAA with custom 3D-printed total talus replacement (TAA-TTR). METHODS: We retrospectively reviewed consecutive patients who underwent TAA-TTR between September 2020 and December 2023. Indications included talar component collapse following prior TAA or talar AVN with ankle and subtalar arthritis. Subtalar arthrodesis was performed using 2 screws with use of bone marrow aspirate concentrate. Primary endpoint was complication rate; secondary endpoints included reoperations, radiographic assessments, and functional recovery milestones. RESULTS: Eighteen patients (10 females, 8 males; mean age 57.8 ± 10.8 years) were analyzed at mean follow-up of 36.8 ± 16.6 months, after excluding 2 with <12 months' follow-up. Nine had talar AVN and 9 had failed TAA. The complication rate was 33.3% (95% CI: 15.2%-57.3%) (AVN group 44%, revision TAA group 22%). Six patients experienced complications: superficial surgical site infection (SSI) (1), deep SSI requiring debridement surgery (2), extensor hallucis longus rupture (1), nerve-related complication (1), and asymptomatic Chopart joint subluxation (1). Two patients required serial operations, including 1 below-knee amputation for persistent pain and infection. Reoperation rate was 11.1% (95% CI: 3.1%-32.8%). Patients achieved rapid functional recovery: controlled ankle motion boot transition at mean 19.9 days, full weight-bearing at mean 46.9 days, and regular footwear at mean 10.7 weeks. All patients achieved radiographic osseointegration of talar component to the calcaneus. CONCLUSION: TAA-TTR represents a viable motion-preserving procedure in this challenging population. Although patients achieved relatively rapid functional recovery and transition to regular footwear, rigorous selection remains key. This approach demonstrates a manageable complication rate while addressing tibiotalar and subtalar pathology simultaneously. LEVEL OF EVIDENCE: Level IV, retrospective case series.