title: Shoulder injuries in overhead athletes. The "dead arm" revisited.
abstract: The following statements summarize this article: Three distinct categories of Type 2 SLAP lesions exist: (1) anterior, (2) posterior, and (3) combined anteroposterior. Posterior Type 2 SLAP lesions have distinct clinical and anatomic features that distinguish them from anterior Type 2 SLAP lesions. Posterior and combined Type 2 SLAP lesions can be disabling to overhead-throwing athletes because of posterosuperior instability and anteroinferior pseudolaxity. The Jobe relocation test is positive with posterosuperior pain in patients with posterior or combined anterior-posterior Type 2 SLAP lesions and is negative in patients with anterior Type 2 SLAP lesions. Rotator cuff tears are frequently associated with posterior or combined anterior-posterior SLAP lesions, are lesion-location specific, and typically begin from inside the joint as undersurface tears. Repair of posterior SLAP lesions can return overhead-throwing athletes to full overhead athletic functioning. The peel-back mechanism is a likely cause of posterior Type 2 SLAP lesions. To securely repair the posterosuperior labrum to resist torsional peel-back, sulure anchors must be placed posterior to the biceps at the corner of the glenoid. The repair must be protected against external rotation past 0 degree for 3 weeks to avoid undue premature torsional stresses on the repair from the peel-back mechanism. A tight posteroinferior capsule predisposes to Type 2 SLAP lesions in overhead athletes. Shoulders at risk for the dead arm syndrome have a marked loss of internal rotation caused by contracture of the posteroinferior capsule such that less than a 180 degrees arc of rotation is achieved with the arm abducted 90 degrees (the 180 degrees rule). Type 2 SLAP lesions that cause the dead arm syndrome in overhead-throwing athletes are most likely acceleration injuries that occur in late cocking rather than deceleration injuries in follow-through. Rehabilitation of athletes with the dead arm syndrome must include the entire kinetic chain. The root cause of the dead arm syndrome is the Type 2 SLAP lesion.
authors.affiliation: Baylor College of Medicine, Houston, Texas, USA.
authors.forename: S S
authors.initials: SS
authors.lastname: Burkhart
authors.forename: C D
authors.initials: CD
authors.lastname: Morgan
authors.forename: W B
authors.initials: WB
authors.lastname: Kibler
mesh_terms: D001265:Athletic Injuries / Q000473:pathology / Q000601:surgery*; D001484:Baseball; D001696:Biomechanical Phenomena; D006801:Humans; D007593:Joint Instability / Q000473:pathology / Q000601:surgery*; D009985:Orthopedics / Q000379:methods*; D017006:Rotator Cuff / Q000473:pathology / Q000601:surgery; D000070636:Rotator Cuff Injuries; D012421:Rupture; D000070599:Shoulder Injuries; D012785:Shoulder Joint / Q000473:pathology / Q000601:surgery