SPINAL ACCESSORY NERVE: ANATOMICAL VARIATIONS AND ITS SIGNIFICANCE DURING NECK DISSECTION IN HEAD AND NECK CANCER

Spinal accessory nerve plexus includes the spinal accessory nerve with all its Intra- and extracranial connections to other nerves. Neck dissection is an important technique for the treatment of cervical lymph node metastasis in patients with head and neck cancer. Due to the adverse effects of radical neck dissection, a progressively more conservative functional neck dissection including preservation of the spinal accessory nerve is no longer an exception. Iatrogenic injury to the spinal accessory nerve can have medico-legal implications. Despite the presence of many described techniques to locate the nerve, it still remains vulnerable to damage during neck dissection due to its variations in the course and relations with other structures. Since the introduction of functional neck dissection, various modi?cations have been made to reduce the adverse effects of radical neck dissection. This paper describes the variations of the spinal accessory nerve in the neck and surgical significance which will guide head and neck oncosurgeons in imbibing adequate knowledge and using efficient techniques during surgical neck dissections.