Accessory nerve palsy following thoracotomy.

A previously unreported cause of 11th cranial nerve palsy is described in a 53-year-old man. Dysfunction of the trapezius branch of the spinal accessory nerve occurred following median sternotomy and was documented by electromyography. This injury resulted in dysfunction of the trapezius muscle with loss of support of the shoulder girdle and pain. The injury may have been due to stretching from sternal retraction or injury secondary to internal jugular venous cannulation.