Surgical Tutorial – Pectoral Fascicle of the Middle Trunk to Spinal Accessory Nerve Transfer. The pectoral fascicle of the middle trunk is an available donor nerve to transfer to restore spinal accessory nerve function. This procedure involves identifying the brachial plexus and the accessory nerve through a supraclavicular exposure. The pectoral fascicle is identified on the anterior aspect of the middle trunk deep to the identified upper trunk. Typically, two pectoral fascicles are identified and the fascicle that elicits a stronger contraction during electrical stimulation is utilized for transfer. The accessory nerve is identified along and deep to the anterior border of the trapezius. In this specific case, the patient had a proximal iatrogenic accessory nerve injury following a carotid endarterectomy four months prior to surgery, which precluded a direct repair of the accessory nerve.