Traumatic spinal accessory nerve palsy.

Spinal accessory nerve sections due to a purely traumatic origin are very rare. The authors report a case in which a total section of the spinal accessory nerve was observed after a glass-penetrating injury. The primary lesion was undiagnosed, and only late physical examination revealed a scapula alata with a deficiency in shoulder protrusion and elevation. Surgical exploration with direct suturing of the nerve was performed 2 months after the initial trauma; full restoration of muscle function was obtained 12 months after the surgical procedure. Pain, the dominant preoperative feature, totally disappeared after restoration of shoulder function. Although infrequent, spinal accessory nerve lesions must always be excluded in cases of penetrating injuries in the posterior triangle of the neck. Emphasis is placed on diagnosis and treatment of this condition.