Connections between the accessory nerve and the posterior root of the first cervical nerve.

The aim of this study was to demonstrate the incidence of absence of the posterior root of the first cervical nerve, and the relation between the accessory nerve and the posterior root of the first cervical nerve in Turkish population. Dissections of the accessory nerve and the posterior root of the first cervical nerve were performed in 49 specimens from 27 formalin fixed cadavers (25 male and 2 female). The type of the connections between the accessory nerve and the posterior root of the first cervical nerve was classified into four types. Type III was the most common type in present study (30.6%). There was a connection between the accessory nerve and the posterior root of the first cervical nerve in this type. The connections demonstrated in this study are important in the etiology and surgical treatment of the spasmodic torticollis.