This is a CAM type lesion / deformity of the femoral neck.

• There is convexity of the supero lateral femoral head neck junction.

• The normal supero lateral femoral head neck junction should be concave like the inferior junction.

• The convexity may be diffuse or localised.

• This can predispose (but doesn’t always) to femoro-acetabular impingement.

Convexity of the anterior superior femoral head neck junction (Pink arrow). Compare with normal concavity (Green arrow).