Accessory nerve palsy following carotid endarterectomy. Report of two cases.

Two patients who had an accessory nerve palsy following carotid endarterectomy are presented. Both patients had high carotid bifurcations necessitating unusually high retraction and dissection. The ipsilateral accessory nerve was injured in the anterior cervical triangle in both cases. It is believed that vigorous lateral retraction of the superior aspect of the sternocleidomastoid muscle led to a stretch injury of the nerve. The symptoms completely resolved in both patients within 6 months.