Pectoralis major muscle injuries: evaluation and management.

Pectoralis major muscle tears are relatively rare injuries that primarily occur while lifting weights, particularly when doing a bench press. Complete ruptures are most commonly avulsions at or near the humeral insertion. Ruptures at the musculo-tendinous junction and intramuscular tears usually are caused by a direct blow. The patient may hear a snap at the time of injury and report pain, weakness, swelling, or muscular deformity. Physical examination can reveal ecchymosis, a palpable defect, asymmetric webbing of the axillary fold, and weakness on resisted shoulder adduction and internal rotation. A detailed history and physical examination can be augmented by radiologic studies, including magnetic resonance imaging. Nonsurgical treatment is now recommended only for the older, sedentary patient or for proximal muscle belly tears. Surgery, whether early or delayed, consistently yields superior results compared with nonsurgical management. Prompt diagnosis and timely intervention likely will produce improved results.