Location

Hip

Diagnosis

Avascular necrosis

Discussion

A radiograph of a left hip joint, which reveals a thin, curvilinear lucent line parallel to the cortical margin of the femoral head. Interruption of the blood supply to the femoral head leads to ischemic necrosis of the marrow and bone that it supplies. Eventually, the bone infarcts and insufficiency fractures may ensue. Fractures that occur in the subchondral bone may be recognized by a crescentic lucent zone that separates the fragment from the remainder of the femur.

Reference

Norman A, Bullough P: The radiolucent crescent line: An early diagnostic sign of avascular necrosis of the femoral head. Bull Hosp Joint Dis 1963, 24:99-104.

Figures

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Attachments:


hipavncrescentap.jpg (image/jpeg)