Pseudo-AFF on hip DXA

Case Description:

58 year old woman undergoing DXA after right hip fracture.

Left hip DXA image shows bony protrusion from the lateral cortical subtrochanteric femur. Periosteal stress reaction from an atypical femur fracture (AFF) might be considered, but the patient had received no anti-osteoporosis therapy, there were no symptoms and there was no endosteal reaction. Further review shows a history of multiple hereditary exostoses, as seen on x-ray for the left hip and knees.

This highlights the importance of clinical correlation and imaging review before diagnosing an AFF — there is always a differential to consider.

Credit: William D. Leslie, MD FRCPC MSc CCD, University of Manitoba

References:

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