Spinal Accessory Nerve Palsy: Evaluation of Four Atypical Cases

Spinal accessory nerve palsy commonly occurs as a result of iatrogenic injury usually during lymph node excision in the posterior cervical triangle. Numerous alternative etiologies are described. Trauma is the most common cause of non-iatrogenic palsy. Sometimes, the cause of the palsy cannot be identified. Here, we report four atypical cases of isolated spinal accessory nerve palsy leading to trapezius muscle dysfunction. In one patient, accessory nerve palsy developed after reduction mammaplasty and abdominoplasty surgery (Case 1). One of them experienced a stretch injury due to weight lifting (Case 2). In one patient, a clear reason could not be identified (Case 3). In a 12-year-old girl, accessory nerve palsy was caused by her heavy school bag (Case 4). All three segments of trapezius muscle were involved in all cases, except for the case 1 who had only the upper segment involvement. The patients were followed clinically and electrophysiologically for 24-30 months. Both cases 1 and 2 showed complete recovery within six months, whereas cases 3 and 4 showed incomplete recovery. The clinical similarities and differences, and also the neurophysiological findings of cases are discussed in this paper. Our long-term follow-up findings may help us to understand the mechanism and the natural course of the accessory nerve palsies. Turk J Phys Med Rehab 2011;57:248-52.