Avulsion fracture of the anterior inferior iliac spine

A 15 year old boy complains of pain in the right groin after kicking against a hard ball. The physician requests an ultrasound of the groin region for excluding muscle or tendon rupture.



The ultrasound didn't show any abnormalities of the muscle or tendon structures. What we do see is a loose bone fragment at the proximal end of the m. rectus femoris.



X ray of the right hip shows an avulsion fracture of the anterior inferior iliac spine. This is where the m. rectus femoris inserts. An avulsion is caused by a hyperextension movement of the leg.