Reconstruction of the spinal accessory nerve with an anastomosis to the dorsal C3 branch: technical note

Most lesions of the spinal accessory nerve are of traumatic origin. If the proximal part is sectioned next to its exit from the cranial base, the reconstruction might be difficult. In such a case, one option is intracranial identification of the spinal accessory nerve and transdural interposition of a graft to its distal stump. Cerebrospinal fluid leaks or infections, caudal nerve palsies, or even spinal neurological deficits are possible complications. From more than 70 patients who underwent selective peripheral denervations for the treatment of spasmodic torticollis in our department, we have learned that the dorsal C1-C6 branches can be sectioned without any functional impairment. The dorsal C2 and C3 branches have diameters comparable to that of the spinal accessory nerve. They contain between 600 and 700 myelinated fibers per square millimeter. Therefore, they seem to be ideal proximal donors for the reconstruction of a severed motor nerve. They may be used in patients with peripheral nerve injuries in the craniocervical region, if other possibilities are not suitable.