Accessory Nerve


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accessory nerve

[ak′ses·ə·rē ‚nərv]
(neuroscience)
The eleventh cranial nerve in tetrapods, a paired visceral motor nerve; the bulbar part innervates the larynx and pharynx, and the spinal part innervates the trapezius and sternocleidomastoid muscles.

Nerve, Accessory

 

(nervus accessorius, or nerve of Willis, after the English physician T. Willis, who first described it in 1664), the 11th pair of cranial nerves.

The accessory nerve originates in the medulla oblongata and the spinal cord. It emerges from the cranial cavity with the glossopharyngeal and vagus nerves through the jugular foramen and supplies motor fibers to the sternocleidomastoid muscle on the neck (with unilateral contraction, this muscle inclines the head to the side and turns the face in the opposite direction) and to the trapezius muscle on the back (it raises the pectoral girdle and adducts the scapula). Some of the fibers of the accessory nerve are connected to the vagus nerve and with its branches reach the muscles of the soft palate, the pharynx, and the larynx.

References in periodicals archive ?
The patient underwent en bloc resection of the mass by a head and neck surgeon, with preservation of the spinal accessory nerve.
The electrophysiological results showed that 19 patients had a definite decremental response in the trapezius, yet there was no sign of spontaneous potential or neurogenic motor unit potentials in the EMG of the sternocleidomastoid muscle, which is supplied by the accessory nerve as well.
Specimens of bilateral neck dissection with preservation of the spinal accessory nerve, internal jugular vein and sternocleidomastoid muscle.
There is no reported damage to the spinal accessory nerve when the procedure was undertaken with the desired level of expertise.
The accessory nerve was visualized and protected in the deep layer of the trapezius muscle.
Spinal accessory nerve can be a cause of scapular winging and shoulder dysfunction.
Although Merrell has concluded by recommending shoulder restoration should focus on either a spinal accessory nerve to suprascapular nerve transfer or dual nerve transfer to both suprascapular nerve (SSN) and axillary nerve, the above 2 cases where ICNs were used for SS neurotization achieved 100% M3 or more shoulder abduction.
Ultrasonography of the accessory nerve: normal and pathologic findings in cadavers and patients with iatrogenic accessory nerve palsy.
Whereas haemorrhage chyle leak and accessory nerve palsy was noted in 1.7% for each entity (Table 2).
In the case of cervical plexus, brachial plexus, and accessory nerve schwannomas, there were no aggravated neurological deficits.
Spinal accessory nerve palsy commonly occurs as a result of iatrogenic injury, usually during lymph node excision in the posterior cervical triangle.
Oswaldo Suarez gets the credit for popularizing functional neck dissection where by the spinal accessory nerve is carefully preserved to the extent where tumor involvement allows.2

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