MRCP UK EXAMINATIONS

Detailed explanation-1: -Trapezius and sternocleidomastoid muscles have branchiomeric origin; the afferents that derive from these muscles reach the nucleus of the solitary tract. The trapezius muscle elevates, lowers, adduces and abducts, and externally rotates the scapula. It extends the head by rotating it to the opposite side.

Detailed explanation-2: -The accessory nerve provides motor function (movement) to two muscles essential to neck and shoulder movement, the sternocleidomastoid (SCM) and the trapezius, as well as to the larynx (voice box) and other structures in the throat. It’s the 11th of the 12 cranial nerves and is often referred to as CN XI.

Detailed explanation-3: -The accessory nerve, also known as the eleventh cranial nerve, cranial nerve XI, or simply CN XI, is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. It is classified as the eleventh of twelve pairs of cranial nerves because part of it was formerly believed to originate in the brain.

Detailed explanation-4: -The accessory nerve is a motor nerve that supplies the sternocleidomastoid and trapezius muscles. Some texts consider the ‘cranial’ root, which arises from the caudal portion of the nucleus ambiguus, as part of the accessory nerve.

Detailed explanation-5: -The accessory nerve (Fig. 1), named after Thomas Willis (Willis, 1965) cranial nerve XI, innervates the sternocleidomastoid (SCM) and trapezius muscles.