[A rarely diagnosed cause of acute hip and groin pain in an 86-year-old woman].

This case report illustrates a common clinical issue, where an 86-year-old woman was being referred to an emergency department because of severe hip and groin pain. The primary examination ruled out proximal femoral or pelvic fracture, and after an MRI was performed, the unusual cause of her pain was revealed: a rupture of the iliopsoas tendon at its insertion on the lesser trochanter. We present the causes and dispositions for iliopsoas tendon rupture among elderly, as well as the diagnostic order of imaging techniques and treatment for this condition.