Disorders of accessory [11th] nerve

This code represents a neurological dysfunction affecting the accessory nerve, also known as the eleventh cranial nerve. This nerve primarily controls the sternocleidomastoid and trapezius muscles, impacting head movement and shoulder elevation. Disorders can manifest as weakness, atrophy, or paralysis of these muscles.

This code is appropriate when documentation indicates a diagnosed disorder of the accessory nerve, such as accessory nerve palsy, injury, or entrapment. Clinical notes should describe specific deficits related to sternocleidomastoid or trapezius muscle function, such as difficulty shrugging shoulders or turning the head.

• Specify the underlying cause of the accessory nerve disorder if known and documented (e.g., trauma, tumor) with an additional code.
• Differentiate from general muscle weakness or pain not directly attributed to accessory nerve dysfunction.
• Ensure documentation clearly links the observed symptoms to a disorder of the 11th cranial nerve.