Mid-term results of subcapital realignment of chronic slipped capital femoral epiphysis using surgical hip dislocation: a prospective case series

BACKGROUND: Slipped capital femoral epiphysis (SCFE) requires surgical treatment when diagnosed. The surgical management of moderate to severe SCFE remains an area of controversy among pediatric orthopedic surgeons. The severity of slippage, the viability of the femoral epiphysis, and the method of surgical management determine the long-term clinical and radiographical outcome. This study sought to evaluate the mid-term results of subcapital realignment of chronic stable slipped femoral epiphysis with open physis using surgical hip dislocation. MATERIALS AND METHODS: This study was a prospective case series of adolescents with moderate or severe degrees of chronic SCFE who had undergone subcapital osteotomy using the surgical hip dislocation technique. The Harris Hip Score (HHS) was used to assess functional outcomes at 6 years of follow-up. A HHS of ≥ 80 points was considered satisfactory. Postoperative radiological outcomes were evaluated using epiphyseal-shaft angles and alpha angles. Postoperative complications were observed. RESULTS: This study included 40 patients, 32 (80%) males and 8 (20%) females, with a mean age of 14.1 ± 1.8 years. There was a statistically significant improvement in the mean HHS from 45 ± 12.3 preoperatively to 91.8 ± 11.6 points at 6 years of follow-up. The mean epiphyseal-shaft angle reduced from 60.5 ± 15.3° preoperatively to 10.3 ± 2.4° postoperatively, P < 0.001. The mean alpha angle reduced from 72.5 ± 10.1° preoperatively to 40.4 ± 6.4°, P < 0.001. Four (10%) patients showed femoral head avascular necrosis (AVN). CONCLUSIONS: Subcapital realignment of chronic SCFE can achieve satisfactory clinical and radiological outcomes, but femoral head AVN remains a risk. Level of evidence Level IV.