Junior call case 4

Patchy sclerotic appearance of the femoral heads bilaterally consistent with AVN.

Early AVN findings on x-ray are subtle, including slight mixed sclerotic and lytic change. At this point, MRI can be of great value, as it is extremely sensitive for both marrow edema and the hallmark MRI finding, low signal intensity serpiginous lines.
Later AVN findings on x-ray are diagnostic, including flattening of the femoral head and subchondral lucency, in addition to more prominent mixed sclerotic and lytic change.
One clue to help distinguish late AVN from severe osteoarthritis is that AVN affects only one side of the joint (the femoral head), while severe OA equally affects both sides of the joints.

Accession: CL0753

Study description: Pelvis