Complications of neck-node biopsy
One of the reasons why biopsy of neck nodes features relatively frequently in medico-legal practice is the potential for nerve injury. Lymph nodes in the anterior triangle of the neck can be biopsied relatively safely. They may, indeed, be adherent to the internal jugular vein, but any competent surgeon should be able to detect this and dissect the node away from the vein. In the posterior triangle, however, the accessory (11th cranial nerve) lies superficially and is easily injured by operations on lymph nodes in the posterior triangle fat. Such nodes are commonly in close proximity to the nerve. Unfortunately, some surgeons who lack close familiarity with head and neck surgery fail to appreciate this point, and may even delegate the biopsy of a posterior triangle lymph node to a relatively junior colleague. The crowning error, however, is to perform the biopsy under local anaesthetic. Where a small lymph node is involved this is tempting, but the local anaesthetic infiltration obscures the effects of any stimulus to the accessory nerve, and it is contraindicated under these circumstance. If it is essential to biopsy a posterior triangle lymph node this should be done under general anaesthetic, without muscle relaxation and preferably with the use of a nerve monitor with electrodes sited in the trapezius muscle. Under these circumstances the risk of division of the accessory nerve is minimised.