cranial nerve XI palsy

Last reviewed 10/2021

Accessory nerve palsy is paralysis of the muscles supplied by the accessory nerve, cranial nerve XI.

Clinical features include:

  • possible loss in function and muscle mass in the trapezius and the sternomastoids

During the neurological examination the function of the accessory nerve is assessed as follows:

  • sternocleidomastoid - turning of the head against a force applied by the examiner
  • trapezius - the ability to shrug against a downward force applied the examiner