Arthroscopic Anatomy, Variants, and Pathologic Findings in Shoulder Instability

Dynamic shoulder examination of posterior-superior impingement in a young overhead athlete while the arthroscope is in the posterior portal (left shoulder). Note the marked hypervascularity of the labrum on the right, the fraying of the supraspinatus tendon, and the roughening of the cartilage near the supraspinatus insertion, where pathologic contact persists during high external-abduction motion of the shoulder.

Dynamic probing of superior labrum/biceps anchor (right shoulder). Note the difference in the stability of the biceps anchor in both examples. In the first example the anchor/superior labrum is absolutely stable. In the second case (world champion in karate fighting), the labrum can be widely lifted up and is grossly unstable (type II SLAP).