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What is A 43 year old woman came with a large abscess in the middle of the right posterior triangle of the neck. The physician incised and drained the abscess. Five days later the patient noticed that she could not extend her right hand above her head to brush her hair. What is the cause and explain in detail?
Spinal accessory nerveThe damages to spinal accessory nerve damage the trapezius muscle that leads to loss of hyperabduction of arm.reference- Clinical Anatomy for students, a problem-solving approach, Neeta v Kulkarni, 2nd edition, page no.463