2017 AWARD WINNER

Introduction: Ischiofemoral impingement (IFI) is a cause of posterior hip pain resulting from impingement of the ischium and the lesser trochanter of the femur. Congenital or acquired narrowing of the ischiofemoral space results in compression or impingement of the quadratus femoris muscle, leading to edema and pain, with sciatic nerve irritation occurring in some patients. Lesser trochanterplasty, ischioplasty, or both have been proposed as effective treatment options for patients in whom nonsurgical treatment fails.

Purpose: This video shows the gross anatomy of the deep gluteal space, the abnormal relationship between the lesser trochanter and the ischium, the quadratus femoris muscle and the sciatic nerve, and endoscopic decompression of IFI. In addition, the video details the clinical presentation of patients with IFI and assesses the outcomes of endoscopic treatment and lesser trochanterplasty.

Methods: The video details the gross anatomy of the deep gluteal space and demonstrates endoscopic decompression of IFI. Thirteen patients with IFI who underwent endoscopic treatment via resection of the lesser trochanter were retrospectively reviewed. Outcomes were assessed at a mean follow-up of 10 months (range, 6 to 16 months) using the modified Harris hip score and the visual analog scale score for pain. Physical examination tests provoking impingement between the lesser trochanter and the ischium, including the IFI test, and reproducible pain located lateral to the ischium during the long-stride walking test, were used for diagnosis of IFI. The presence of quadratus femoris muscle edema and a decreased ischiofemoral space on MRI also was necessary for a diagnosis of IFI.

Results: Thirteen subjects (all women) with a mean age of 40.2 years (range, 14 to 66 years; standard deviation [SD] ± 15.8 years) were included in the study. The long-stride walking test and the IFI test were positive in all the patients. The mean ischiofemoral space measured on MRI was 9.6 mm (range, 8 to 12 mm; SD ± 1.3 mm). The mean modified Harris Hip Score increased from 48.6 preoperatively (range, 25 to 65; SD ± 11.9) to 82.8 at final follow-up (range, 35 to 95; SD ± 15.8). The mean visual analog scale score for pain decreased from 9.3 preoperatively (range, 8 to 10; SD ± 0.76) to 2.53 at final follow-up (range, 0 to 5; SD ± 2.29).

Conclusion: Endoscopic lesser trochanterplasty is an effective treatment option for patients with posterior hip pain who have radiologic and clinical features of IFI.