Posterosuperior notch defect in humeral head
Due to impingement against glenoid rim during anterior dislocation
On axial MR, seen at or above the level of corocoid (beware of normal flattening of humeral head below this level)
Associated with Bankart lesion
References:
Robinson G et al. Normal anatomy and common labral lesions at MR arthrography of the shoulder. Clin Rad 61 (805-821)
Image Gallery:
