An Unusual Variation of the Accessory Nerve

Abstract

In this manuscript, we report an anatomic variation of the spinal accessory nerve for the first time in the literature. The spinal accessory nerve was exited from the skull base in duplicate, and these two branches merged in the anterior triangle of the neck and continued as a common branch in a 68-year-old male patient who underwent total laryngectomy and bilateral modified neck dissection.

Keywords

• Anatomy
• anatomic variations
• cranial nerves
• spinal accessory nerve

References

1. 1. Khaki AA, Shokouhi G, Shoja MM, et al. Ansa cervicalis as a variant of spinal accessory nerve plexus: a case report. Clin Anat 2006;19(6):540-3. google scholar
2. 2. Brown H. Anatomy of the spinal accessory nerve plexus: relevance to head and neck cancer and atherosclerosis. Exp Biol Med (Maywood) 2002;227(8):570-8. google scholar
3. . McGarvey AC, Chiarelli PE, Osmotherly PG, Hoffman GR. Physiotherapy for accessory nerve shoulder dysfunction following neck dissection surgery: a literature review. Head Neck 2011;33(2):274-80. google scholar
4. 4. Saman M, Etebari P, Pakdaman MN, Urken ML. Anatomic relationship between the spinal accessory nerve and the jugular vein: a cadaveric study. Surg Radiol Anat 2011;33(2):175-9. google scholar
5. 5. Symes A, Ellis H. Variations in the surface anatomy of the spinal accessory nerve in the posterior triangle. Surg Radiol Anat 2005;27(5):404-8. google scholar
6. 6. Overland J, Hodge JC, Breik O, Krishnan S. Surgical anatomy of the spinal accessory nerve: review of the literature and case report of a rare anatomical variant. J Laryngol Otol 2016;130(10):969-72. google scholar
7. 7. Tubbs RS, Ajayi OO, Fries FN, Spinner RJ, Oskouian RJ. Variations of the accessory nerve: anatomical study including previously undocumented findings-expanding our misunderstanding of this nerve. Br J Neurosurg 2017;31(1):113-5. google scholar
8. 8. Salgarelli AC, Landini B, Bellini P, Multinu A, Consolo U, Collini M. A simple method of identifying the spinal accessory nerve in modified radical neck dissection: anatomic study and clinical implications for resident training. Oral Maxillofac Surg 2009;13(2):69-72. google scholar

9. 9. Watkinson JC, Gleeson M. 2016. Neck: the accessory nerve. In: Standring S, editor. Gray’s Anatomy: The Anatomical Basis of Clinical Practice. 41st ed. London: Elsevier Limited P 467-8. google scholar
10. 10. Ouaknine G, Nathan H. Anastomotic connections between the eleventh nerve and the posterior root of the first cervical nerve in humans. J Neurosurg 1973;38(2):189-97. google scholar
11. 11. Hagenah R, Kosak M, Freckmann N. Anatomic topographical relationship of the intraspinal accessory root to the upper cervical roots and to the vessels of the cranial cervical region. Acta Anat (Basel) 1983;115(2):158-67. google scholar
12. 12. Midwinter K, Willatt D. Accessory nerve monitoring and stimulation during neck surgery. J Laryngol Otol 2002;116(4):272-4. google scholar