Valgus Slipped Capital Femoral Epiphysis: Pathophysiology of Motion and Results of Intracapsular Realignment.

OBJECTIVES: The purpose of this study was to report (1) a different but specific pattern of impingement in hips involved with valgus slipped capital femoral epiphysis (valgus SCFE) and (2) the results of surgical treatment using intracapsular realignment techniques.

DESIGN: Case series.

SETTING: Multiple academic centers.

PATIENTS: Six patients with 8 involved hips referred for valgus alignment of proximal femoral epiphysis (valgus SCFE).

INTERVENTION: Intracapsular realignment osteotomy combined with periacetabular osteotomy if needed.

MAIN OUTCOME MEASUREMENT: The clinical and radiographical results and pathophysiology of motion.

RESULTS: Eight hips in 6 patients were treated with subcapital (5 hips) or femoral neck (3 hips) osteotomy for realignment. The medially prominent metaphysis created an inclusive impingement at the anterior acetabular wall, whereas the high coxa valga favored impacting impingement at the posterior head-neck junction. The mean preoperative epiphyseal-shaft angle of 110.5 (range 90-125 degrees) was reduced to 62 degrees (range 55-70 degrees) postoperatively. At the last follow-up, all but 1 hip were pain-free and impingement-free, with normal range of motion. One hip was replaced after repeated attempts of correction. The overall hip functional result using modified Merle d'Aubigne scoring system was excellent in 5 hips (18-16 points), good in 2 hips (16-15 points), and poor in 1 hip (6 points).

CONCLUSIONS: Impingement in valgus SCFE deformity is specific and complex. Anatomical realignment can lead to favorable results by the restoration of normal morphology and impingement-free range of motion.

LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.