Dual spinal accessory nerve: caution during neck dissection.

Preserving the spinal accessory nerve (SAN) is an important step in the modern-day neck dissection to avoid postoperative functional morbidity in patients. This goal can become technically difficult, especially, when rare anatomical variations are encountered. We present a case of dual SAN in a patient undergoing selective neck dissection for oral squamous cell carcinoma. Both SANs were preserved and patient had no shoulder dysfunction postoperatively. We take this opportunity to emphasise that meticulous dissection is the only proven way to preserve the nerve. And that surgeons should be aware of this anatomical variation. SAN should be subjected to minimal traction during neck dissection to avoid tension neuropraxia and long-term shoulder dysfunction. © BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.