Total Ankle Arthroplasty in Valgus Deformity

CATEGORY: Ankle Arthritis INTRODUCTION/PURPOSE: Total ankle replacement use has increased among patients with end-stage ankle arthritis. Substantial coronal plane deformity is usual in that context. In addition, recent literature shows a trend towards the extension of the indication of total ankle arthroplasty in increasingly severe coronal deformities, showing good results when correct alignment is achieved. Nevertheless, the results of lateral transfibular total ankle replacement (LTTAR) in valgus has not been extensively studied. We aimed to evaluate if the outcomes of LTTAR in ankles with valgus deformity are similar with those with no major deformity. METHODS: This retrospective cohort study included 228 LTTAR. Patients were classified into 2 groups according to the preoperative coronal plane tibiotalar angle (TTS): neutral (less than 10° of coronal deformity, 209 patients) and valgus (above 10° of valgus, 19 patients). Clinical evaluation was performed using American Orthopaedic Foot & Ankle Society Score (AOFAS), Visual analogue scale (VAS), short Form 12 Quality of Life (SF-12) regarding its physical (PCS) and mental (MCS) items. Radiographic evaluation considered anteroposterior and lateral ankle radiographs. Surgical times were recorded in all the cases. There were no differences between groups regarding mean age, mean body mass index and follow up. The minimum follow up was 24 months. RESULTS: The average AOFAS, VAS and SF-12 scores improved significantly postoperatively (p-value<0.01), without differences between groups. At final radiographic follow up, the valgus alignment group did not show significant differences with the neutral alignment group regarding TTS, lateral distal tibial angle or anterior distal tibial angle (p-value>0.05). Surgical time was longer in the valgus group (152.84 +- 40.86 mins vs 129.51 +- 52.13), but the difference was not statistically significant. CONCLUSION: Lateral transfibular total ankle replacement in ankles with valgus deformity achieved and maintained correction of coronal alignment in a short term follow up, as obtained in neutral alignment ankles. Clinical outcomes improved significantly regardless preoperative valgus deformity. Additional surgical time may be needed in order to obtain a good deformity correction in a valgus ankle. This short term analysis shows that LTTAR in a valgus ankle seems to be a safe option in experienced surgeons hands.