MR imaging of iliopsoas musculotendinous injuries.

The literature describing iliopsoas compartment injuries is based on case reports and small patient series, mostly in the orthopedic literature.Nevertheless, in recent years, there has been a growing recognition of these injuries. Because many intra-articular and extra-articular bony and soft tissue injuries in the groin may clinically mimic each other, because two or more pathologic entities may coexist, and because athletes are highly motivated to continue with their physical activity, diagnosis of iliopsoas injury is often delayed. Thus, cross-sectional imaging is highly important. MR imaging is most accurate for diagnosing nondynamic diseases of the iliopsoas compartment as well as for ruling out other abnormalities of the hip joint and surrounding structures. When a snapping hip is being investigated or corticosteroid injection is warranted, US can be of help in providing a dynamic study and by guiding the injection.