The treatment of ankle arthritis has seen a sea change over the past few decades, with surgeons becoming increasingly confident in offering total ankle arthroplasty to more patients with disability related to arthritis. Surgeons are emboldened by the expanding clinical literature; however, results that are generalizable to the greater foot and ankle community, sufficient numbers, long-term follow-up, and patient-reported outcomes (PROs) are lacking.

The present study by Hsu and Haddad appears to be only the second clinical series to report survivorship and outcomes measures for the INBONE prosthesis, a fixed-bearing implant with intramedullary fixation of the tibial component. In this series of fifty-nine patients, implant survival was 97% at two years and AOFAS (American Orthopaedic Foot & Ankle Society) hindfoot scores and VAS (visual analog scale) pain intensity were significantly improved. However, the 44% complication rate, 24% reoperation rate, and nearly 9% revision rate for talar component subsidence at an average of nearly three years of follow-up are of concern. Validated PRO measures and functional assessments such as those reported in recent studies would have been of interest.

The only other clinical series to report on the INBONE prosthesis also evaluated fifty-nine patients within a larger cohort of 103 patients; outcomes at two years were assessed in relation to preoperative coronal-plane deformity. Although subgroup analyses of the INBONE prostheses and the other prosthesis design were not performed, AOFAS scores and the reoperation rate of nearly 20% were similar to those in the present study, but with only one patient undergoing implant revision. The authors reported patient health status, validated measures of ankle function, and measured functional assessments.