Iatrogenic injury to the spinal accessory nerve is one of the most common causes of trapezius muscle palsy. Dysfunction of this muscle can be a painful and disabling condition because scapular winging may impose traction on the soft tissues of the shoulder region, including the suprascapular nerve. There are few reports regarding therapeutic options for an intracranial injury of the accessory nerve. However, the surgical release of the suprascapular nerve at the level of the scapular notch is a promising alternative approach for treatment of shoulder pain in these cases. The author reports on 3 patients presenting with signs and symptoms of unilateral accessory nerve injury following resection of posterior fossa tumors. A posterior approach was used to release the suprascapular nerve at the level of the scapular notch, transecting the superior transverse scapular ligament. All patients experienced relief of their shoulder and scapular pain following the decompressive surgery. In 1 patient the primary dorsal branch of the C-2 nerve root was transferred to the extracranial segment of the accessory nerve, and in the other 2 patients a tendon transfer (the Eden–Lange procedure) was used. Results from this report show that surgical release of the suprascapular nerve is an effective treatment for shoulder and periscapular pain in patients who have sustained an unrepairable injury to the accessory nerve.
Abbreviations used in this paper: CN = cranial nerve; CPA = cerebellopontine angle; MRC = Medical Research Council.