Accessory nerve conduction in neck dissection subjects.

Evaluation of the accessory nerve and trapezius muscle was performed on eight subjects with neck dissection secondary to oropharyngeal/laryngeal cancer. The latencies and amplitudes of the upper, middle, and lower trapezius muscle in neck dissection subjects were compared to those in healthy subjects similar in age. Subjects after neck dissection showed abnormalities of evoked responses and abnormal spontaneous discharges in electromyographic studies of the upper trapezius. Future serial studies that seek prognostic indicators of shoulder dysfunction common to neck dissection patients are warranted.