Of the many procedures performed by orthopaedic foot and ankle surgeons, few can rival the patient satisfaction, pain relief, and improvement in quality of life and function obtained from a successful total ankle arthroplasty. In stark contrast, some of the most devastating complications, including below-the-knee amputation, can result from failed/infected total ankle arthroplasties. When advising prospective patients about total ankle arthroplasty, we depend on peer-reviewed literature to help develop a treatment algorithm for procedures and implant selection.

Queen et al. provide a well-written and designed prospective analysis of patients who received a mobile-bearing Scandinavian Total Ankle Replacement (STAR) or fixed-bearing Salto Talaris implant. The authors concluded that, at the two-year follow-up evaluation, both groups had significant improvement in walking speed, results of functional tests, patient-reported outcomes, and vertical ground reaction forces. The authors described subtle significant differences between the fixed and mobile-bearing groups. Specifically, the fixed-bearing group had a greater increase in peak plantar flexion moment and the Short Form-36 (SF-36) total score while the mobile-bearing group had greater improvement in the visual analog scale (VAS) pain score and performance on Sit-to-Stand tests.

As the authors acknowledge, the most obvious shortcoming of this study is the lack of randomization for the type of replacement performed. Although the authors comment that selection was based on the preference and clinical judgment of the treating surgeon, their criteria were not described. There was no significant difference in patient age, weight, height, or preoperative tibiotalar alignment between implant groups. However, there were differences between groups with regard to the preoperative SF-36 total score and VAS pain score (Figs. 1 and 2 in the article by Queen et al.). Since these preoperative differences were of much greater magnitude than the postoperative differences, it is difficult to draw meaningful conclusions based on the comparison of these nonrandomized groups.