[A boy with acute pain in his right buttock].

A 14-year-old boy presented to the emergency department with pain in his right buttock after a breakdance move. He got injured while simultaneously hyperflexing his hip and extending his knee. Upon physical examination he had tenderness over his right ischial tuberosity and an inability to perform combined hip extension and knee flexion. Radiography and CT-imaging showed an avulsion fracture of the ischial tuberosity.