Spinal accessory nerve function following neck dissection.

Spinal accessory nerve (SAN) function was evaluated by electromyography (EMG) and muscle testing in 36 patients who underwent neck dissection with SAN preservation. The results emphasized that SAN function was relatively good after conservative neck surgery. Muscle testing findings showed better function than did EMG findings. After surgery the trapezius muscle functioned more efficiently than the sternocleidomastoid (SCM) muscle probably because of the more traumatic surgical handling of both the SCM muscle and its SAN branch. In order to obtain the functional advantages of SAN preservation, the authors suggest that the conservative procedure in radical neck dissection be used whenever warranted by oncologic diagnosis.