A Long-Head of Biceps Tendon Rupture in a Fast Pitch Softball Player: A Case Report
Rupture of the long head of the biceps tendon (LHBT) is a common tendon injury, and can be the result of a degenerative process or a sudden traumatic event. Compression and repetitive trauma to the tendon as it passes beneath the subacromial arch can result in microtears that weaken the tendon and lead to rupture. Traumatic ruptures in young athletes are seldom described but can occur during a sudden overload event where forced extension of the elbow against an eccentrically contracting biceps muscle overcomes the tensile strength of the tendon. Jobe et al suggested that LHBT rupture in throwers can be associated with glenohumeral instability, and when forces during activity exceed the anterior static restraints, the muscles fatigue, resulting in anterior and superior migration of the humeral head and worsening of the pre-existing subacromial impingement.
Previous case reports of LBHT ruptures in younger athletes have been in weightlifters and been attributable to anabolic steroid abuse. To our knowledge, there is no report in the literature of an isolated LHBT in an underhand thrower. In our experience, biceps tenosynovitis and anterior shoulder pain are common complaints in elite windmill pitchers. It is possible that the unique stresses placed on the LHBT, due to increased biceps muscle activity or increased tendon excursion in the windmill-pitching motion, creates a risk for tendinosis and rupture.