Pelvic deformity secondary to tensor fascia lata tightness associated with desmoid tumor.

The iliotibial band is a thick, condensed fascia that, when contracted, leads to a hip flexion, abduction, and external rotation contracture in addition to other joint contractures. Iliotibial band tightness occurs secondary to iliotibial band friction syndrome, which commonly occurs at the lateral femoral epicondylar region. However, a proximal cause of iliotibial band/tensor fascia lata friction syndrome leading to a secondary hip contracture is swelling around the hip; this swelling being a desmoid tumor has not been explicitly described in the literature. The authors present a rare case of a hip contracture in a 28-year-old active man who presented with a functionally disabling hip flexion contracture of 20° with further flexion possible up to 130°, a 45° abduction contracture, and a 20° external rotation contracture with further rotation possible up to 40° with a bony hard swelling in the left gluteal region. Ober’s test was positive. Opposite hip and spine examinations were normal. The goals of treatment were to establish the causality between the 2 and to diagnose the etiology of the gluteal mass. Radiographs were normal, with only a pelvic obliquity evident. Magnetic resonance imaging revealed an extra-articular mass abutting the iliac blade. Histopathology confirmed the mass to be a desmoid tumor in the left gluteal region. A wide surgical excision of the mass was performed with negative margins; no postoperative radiotherapy was administered. After rigorous physiotherapy, the hip deformity disappeared at 6 months and there was no evidence of recurrence at 2.5-year follow-up, with the patient able to sit cross-legged and squat.