Brief report: identification of the great auricular nerve by ultrasound imaging and transcutaneous nerve stimulation.

Superficial cervical plexus neuropathy after interscalene brachial plexus block affects about 8% of patients postoperatively. One of the nerves involved in superficial cervical plexus neuropathy is the great auricular nerve. We report success in identification of the great auricular nerve with ultrasound and transcutaneous nerve stimulation in a clinical setting in the majority of cases (95% lower confidence limit 63%). Identification of the nerve is significantly more difficult in female and in obese patients. Further studies will allow determination of whether this information will help to reduce the incidence of superficial cervical plexus neuropathy.