Subtrochanteric osteotomy effectively treats femoroacetabular impingement after slipped capital femoral epiphysis

Femoroacetabular impingement causing pain and deformity often follows in situ pinning for severe, stable (Grade III) slipped capital femoral epiphysis. We asked whether a transverse percutaneous subtrochanteric osteotomy using external fixation could decrease pain, restore function and motion, and improve radiographic outcome. We performed a transverse subtrochanteric osteotomy with external fixation in 13 patients who had prior in situ pinning for severe slipped capital femoral epiphysis. All patients had decreased function, limited range of motion, pain with ambulation, and a limp after in situ pinning. We evaluated the patients using Southwick's categorical classification. The patients' ages ranged from 11 to 17 years; there were five boys and eight girls. The minimum followup was 32 months (average, 43 months; range, 32-92 months). Considering pain as a criterion, 11 patients had good or excellent results (two fair). Twelve patients had good results (one fair) for function, 11 had good results (two fair) for limping, and 11 had good or excellent results (two fair) for motion. Radiographic parameters showed nine good results and four fair results. Subtrochanteric three-dimensional correction using a percutaneous transverse osteotomy and external fixation effectively improved symptoms of femoroacetabular impingement after pinning of a severe slipped capital femoral epiphysis. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.