LAUSR

Background: Ischiofemoral impingement is an often unrecognized cause of hip pain in adolescents. It is caused by abnormal contact between the proximal femur and the ischium. The aim of our work is to describe clinical presentation, imaging findings and functional outcomes of ischiofemoral impingement in adolescents. Methods: We performed a retrospective study. Clinical files were reviewed (age, sex, type and duration of symptoms and hip physical examination). Imaging findings were evaluated in pelvis radiographs (presence of coxa profunda, acetabular protrusio, Wiberg angle, femoral neck shaft angle and acetabular retroversion) and in MRI (quadratus femoris edema, measurement of ischiofemoral and quadratus femoris space). Lower extremity functional scale (LEFS) were used to measured response to a physiotherapy protocol. Also relapse and time to sports return were recorded. Results: 24 hips, two bilateral in 20 female patients and 2 male patients, with 13 years-old on average (9-18) were obtained. Main symptom was hip pain with latency to consultant of 9 days on average (2-14). All patients practiced school sports, the most frequent was gymnastics. Positive FADIR test, ischiofemoral impingement test and pain on palpation of the ischium and gluteus medius were found in everyone. The median of Wiberg angle was 37º (25-48), femoral shaft angle 138º (128-144), and coxa profunda was present in 5 hips. MRI showed 13 hips with quadratus femoris edema, one with muscle atrophy, ischiofemoral space was 20 mm on average (16-25) and quadratus femoris space 17 mm on average (13-21). Our physiotherapy protocol was followed for all patients with a median of 18 sessions (10-30). LEFS improved from 56.4% (30-93) to 92% (80-100) (p=0,02). Time to turn asymptomatic was 6 months on average (3-13). With 2 years follow up, 2 hips had recurrence of symptoms. Time to sports return was 5 months on average (3-7). Conclusions: Ischiofemoral impingement is cause of hip pain in active female adolescents. X-rays are inespecific and MRI shows typically quadratus femoris edema. Conservative treatment with physiotherapy is an effective method that allows sports return in few months. This is the first report in the literature regards ischiofemoral impingement in pediatric population including results of treatment and return to sports.