CN XI which innervates the sternocleidomastoid and trapezius muscles
Commonly removed during radical neck dissection for head and neck cancers
Iatrogenic
Radical or modified neck dissection
Trauma
Stroke
Radical or modified neck dissection
Spinal accessory neuropathy
Carpal tunnel syndrome
Long thoracic neuropathy
Pronator teres syndrome
Suprascapular neuropathy
Anterior interosseous neuropathy
Axillary neuropathy
Ulnar neuropathy