Comparison of Intermediate- to Long-term Outcomes of 299 Total Ankle Arthroplasties in Ankles with Preoperative Neutral and Moderate to Severe Varus Alignment: A Mean 8.8-Year Follow-up

Research Type: Level 3 - Retrospective cohort study, Case-control study, Meta-analysis of Level 3 studies Introduction/Purpose: Analyses of long-term results after total ankle arthroplasty (TAA) in ankles with preoperative varus deformity with adequate sample sizes remain limited. This study compared the intermediate- to long-term outcomes of TAA in patients with preoperative neutral alignment and moderate to severe varus alignment (≥10°). Methods: A total of 299 consecutive ankles that underwent TAA with a minimum follow-up period of 4 years were included. The varus group (132 ankles) exhibited a preoperative coronal tibiotalar angle of ≥10° of varus, whereas the neutral group (167 ankles) showed a preoperative coronal tibiotalar angle of < 10° of varus or valgus. Clinical outcomes were assessed using visual analog scale pain scores, Ankle Osteoarthritis Scale pain and disability subscores, and ankle range of motion. Prosthesis survivorship and reoperations were also analyzed. Results: The mean follow-up duration was 106.3 months (range, 48–230 months). All clinical scores significantly improved from preoperative assessments to the last follow-up; final scores between the two groups were comparable. The varus group required significantly more concomitant procedures to achieve neutral alignment compared with the neutral group (p < 0.001) and demonstrated a significantly higher prevalence of asymmetric polyethylene wear (p < 0.001). Kaplan–Meier survival analysis showed prosthesis survivorship rates of 93.8% in the neutral group and 93.4% in the varus group at 10 years post-TAA, with no significant difference between the groups (p=0.697). Conclusion: TAA achieved similarly favorable intermediate- to long-term clinical outcomes in both neutral and moderate to severe varus alignment. However, progressive edge-loading in varus ankles may require closer monitoring to mitigate the risk of prosthesis failure.