Cervical Spinal Nerves
The hypopharynx’s uppermost point is at the hyoid bone, which lies at approximately the same level as the 4th-6th cervical vertebrae. The pharynx is innervated by a number of nerves with their roots in the cervical spine. Damage to these nerve pathways can result in problems with the correct functioning of all three sections with ramifications for proper control of the separation of the larynx and oesophagus. Faults in innervation, both motor and sensory, in this area may prevent the two pathways functioning properly.
Motor innervation occurs through the glossopharyngeal nerve (IX), the vagus nerve (X), the allied spinal accessory nerve (XI), and the recurrent laryngeal nerve. Sensory innervation in the oropharynx section occurs as a result of the glossopharyngeal nerve (IX), with the vagus nerve (X) providing for the nasopharynx and the hypopharynx/laryngopharynx. As the sensory fibers from the glossopharyngeal nerve (IX) and the vagus nerve (X) enter the brainstem they are bundled together and terminate in the trigeminal nucleus. The trigeminal nerve (CN5) is responsible for creating a complete sensory map of the face and mouth with pain, touch, temperature and position signals all processed through this nerve. Accordingly, trigeminal neuralgia as a result of disc herniation, disc bulging, spondylolisthesis and spinal kyphosis or slippage, amongst other conditions, can be responsible for serious problems with the innervation of the face, jaw, and pharynx. Facial pain, jaw pain, neck pain, problems with chewing and swallowing, a sensation of a lump in the throat, and muscular spasms in the face, jaw, and neck can all result from compression of the cervical spinal nerves.
Last Updated: 1/11/2011