Ultrasound diagnosis of anterior iliopsoas impingement in total hip replacement.

Iliopsoas impingement syndrome, an infrequent complication of total hip replacement, has been rarely reported in the radiological literature. It follows chronic friction of the posterior aspect of the iliopsoas muscle and tendon against the acetabular cup, a piece of cement, or cup fixation screws. Clinical findings are non-specific and an imaging modality is required to diagnose the condition. Computed tomography (CT) is considered the gold standard imaging modality in evaluating iliopsoas impingement. We report a case of a patient in which the diagnosis was made by ultrasound and later confirmed by CT.