Treatment of ischiofemoral impingement: results of diagnostic injections and arthroscopic resection of the lesser trochanter

Ischiofemoral impingement (IFI) is an often unrecognized cause of hip pain caused by abnormal contact between the lesser trochanter and the ischium. To date, surgical treatment for those whose pain is not relieved by activity modification and steroid injections has not been defined. This study describes our imaging protocol and reports the results of arthroscopic, lesser trochanteric resections that were performed to treat this condition. Seven patients with symptomatic, MRI-documented IFI had ultrasound injections of ropivicaine and steroid into their ischiofemoral space. The injections provided complete but only transient relief of their groin and buttock pain and thus, all seven ultimately had an arthroscopic resection of their lesser trochanter. All hips were evaluated preoperatively and at 3, 6 and 12 months postoperatively with Byrd’s modified Harris hip scoring system. Average age of the seven patients was 46 years and there were five females and one male. Preoperative scores averaged 43 points. After surgery, all patients used crutches for 4–6 weeks, and had 6-week scores that averaged 58 points. The patients and their scores continued to improve and at 6 and 12 months, their scores averaged 86 and 91 points, and none had chronic hip flexor weakness or recurrence of their hip pain or snapping. Arthroscopic iliopsoas tenotomies in combination with a resection of the lesser trochanter will provide complete relief of the painful snapping, groin and buttock pain caused by ischiofemoral impingement.