Hindfoot alignment in total ankle replacement at 2 year follow-uo

Abstract

Category: Ankle Arthritis Introduction/Purpose: End-stage ankle osteoarthritis frequently involves multiplanar malalignment both tibio-talar and subtalar joint. Restoration of the correct position of the tibial and the talar component and of the hindfoot is mandatory for the long-term survival of total ankle replacement. Since patients with ankle osteoarthritis often present concomitant hindfoot deformity, radiographic references are needed to describe deformities. However, the possible compensatory mechanisms of these linked joints are not well known.The aim of this study is to show if there is any difference regarding hindfoot position at 6 months, 1 year and 2 years follow-up. Methods: The study included 68 ankles who underwent Total Ankle Replacment through a later transfibuklar approach between May 2013 and December 2015. The main indications for TAR were: post-traumatic (55 patients, 80.9%) and reumathoid arthritis (5 patients, 7.4%). In these patients the hindfoot view angle was measured 6, 12 and 24 months postoperatively. Furthermore, clinical outcomes were recorded. Patients who underwent hindfoot/midfoot fusions were excluded. Results: The mean hindfoot alignment angle (HAV) was 0.4±0.0 pre-operatively and 0.1±6.2, 0.7±6.2, 1.2±7.0 at 6, 12 and 24 months postoperatively. There was no statistically significant difference in the HAV between follow-up. A statistically significant improvement in clinical scores (AOFAS, VAS and SF.12) was found at each follow-up. The main complications were: 6 hardware removal for intollerance (8,8%), 3 delayed wound healing (4,4%), 1 medial impingement (1,5%). Conclusion: Regarding the hindfoot alignment angle, TAA through a lateral approach showed a good reliability. Furthermore, hindfoot alignment remains stable over time.