Acute flexion contracture correction for failed distal femoral extension osteotomy in arthrogryposis: early results and complications.

Abstract

Distal femoral extension osteotomy (DFEO) is a surgical option for knee flexion contractures in arthrogryposis multiplex congenita (AMC); however, recurrence rates are high in skeletally immature patients. This study evaluated posterior knee release with femoral shortening osteotomy as a revision procedure following failed DFEO in AMC. A retrospective review was performed on patients with AMC with failed prior DFEO who underwent revision surgery between 2021 and 2023. Six patients, ten knees, were identified. Radiographic and clinical measurements were compared using paired t tests. The primary outcome was correction of knee flexion contracture. Secondary outcomes included arc of motion and ambulation. Mean age at revision was 9.8 years (range: 7-11 years). Mean radiographic follow-up was 5.3 months (range: 1.6-17.4 months), and mean clinical follow-up was 10.4 months (range: 3.0-20.7 months). Radiographic flexion contracture improved (75.8 vs. 40.0°; P < 0.001). Clinical flexion contracture improved (48.8 vs. 17.9°; P = 0.001). Maximum clinical flexion was preserved (78.5 vs. 77.0°; P = 0.791). Arc of motion improved (29.7 vs. 59.1°; P < 0.001). Radiographic extension deformity improved (26.9 vs. 4.7°; P < 0.001) and was maintained at follow-up (6.5°; P = 0.255). Two patients (33%) were ambulatory preoperatively; 100% were ambulatory postoperatively. Complications occurred in 6 of 10 knees, none resulting in lasting morbidity. Posterior knee release with femoral shortening is an effective salvage strategy following failed DFEO in AMC. Correction of flexion contracture and improved arc of motion was achieved without sacrificing maximum flexion. DFEO should be reserved for patients approaching skeletal maturity to avoid the need for reoperation.