Differences in Outcomes Following Total Ankle Replacement in Patients with Neutral Alignment Compared with Tibiotalar Joint Malalignment

Background: Excessive tibiotalar malalignment in the coronal plane has been considered by some to be a contraindication to total ankle replacement. The purpose of the present study was to compare clinical outcomes and physical performance measures according to preoperative tibiotalar alignment.

Methods: One hundred and three patients undergoing total ankle replacement were grouped according to coronal plane tibiotalar alignment. Seventeen patients had an excessive deformity (>15° of varus or valgus), twenty-one had moderate valgus alignment (5° to 15° of valgus), twenty-seven had moderate varus alignment (5° to 15° of varus), and thirty-eight had neutral alignment (<5° of varus or valgus). Outcome measures, including the American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score, the Foot and Ankle Disability Index (FADI), the Short Form-36 (SF-36), the timed up and go test (TUG), the four square step test (4SST), and walking speed, were assessed preoperatively and at one and two years after total ankle replacement.

Results: Coronal plane alignment improved following the procedure, with 36.9% of patients having neutral alignment preoperatively as compared with 95% postoperatively. To achieve this alignment, adjunctive procedures, including deltoid ligament release, lateral ligament reconstruction, and posterior soft-tissue releases, were necessary. Significant improvements were seen for the Page: 3 AOFAS pain, function, alignment, and hindfoot scores (p < 0.001) and the SF-36 subscales of body pain, physical function, and role physical (p < 0.001) following total ankle replacement. Walking speed and the FADI, TUG, and 4SST scores also improved significantly (p < 0.001). Subgroup analysis demonstrated no significant differences in clinical outcomes and physical performance measures based on preoperative coronal plane alignment.

Conclusions: Total ankle replacement improves clinical and functional outcomes independent of preoperative tibiotalar alignment when postoperative alignment is restored to neutral at the time of arthroplasty.

Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.