Imaging Case of the Week 69

The following x-rays are from a 34 year old man who felt a sudden pain in his right buttock while playing footie. What can you observe in the x-rays?

Pelvic X-ray

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Right hip

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[peekaboo_link name=”Answer”]Answer[/peekaboo_link] [peekaboo_content name=”Answer”]

The x-rays show a missable fracture which is the avulsion fracture of the right ischial tuberosity. This indicates hamstring avulsion injury as the hamstring muscle originates from the ischium.

Ischial tuberosity avulsion fracture

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Ischial tuberosity avulsion fractures are associated with forceful flexion of the hip with the knee extended and are more common in adolescents than any other age group.

A complication of this fracture can be injury to the sciatic nerve as it runs between the ischial tuberosity and the greater trochanter.

Any patients suffering from this fracture need an orthopaedic follow up for conservative or operative management. Orthopaedic textbooks suggest conservative management for fractures with less than 2 cm displacement; avulsions with greater than 2 cm displacement need ORIF.