Technic and Practice of Chiropractic

by Joy Maxwell Loban

Eye and Muscles, Retina, Optic Nerve: The external muscles of the eye, the four recti and two oblique with the levator palpebrae superioris, are innervated by the Oculomotor, or third cranial, and the fourth and sixth cranial, which receive branches from the cavernous plexus of the sympathetic derived from the internal carotid branch of the superior cervical ganglion. As the ganglion lies in front of the transverse processes of the second, third, and fourth cervical vertebrae, direct impingement upon it by subluxation of one of these vertebrae may cause strabismus or other affection of the external ocular muscles.

The eye-ball receives filaments from the ciliary or ophthalmic ganglion, which in turn is connected with the cervical ganglion by way of cavernous plexus and internal carotid nerve. This pathway controls the radial fibres of the iris and dilates the pupil as a part of the light accommodation reflex mechanism. Loss of pupillary reaction, especially with small pupils, suggests upper cervical subluxation.

The retina, containing the cells of origin of the optic nerve axons and being the special end-organ of the sense of sight has no direct spinal or sympathetic connections but its blood-supply, and therefore its nutrition, is influenced by branches from the sympathetic which enter with the central artery of the retina. Retinal hemorrhage has been cured by cervical adjustment, C 2, 3, or 4.

The conjunctiva is innervated by the sympathetic and by the fifth cranial, or trigeminal.

Olfactory Nerve: Nerve of smell, distributed to the Schneiderian membrane over the upper portion of the nasal septum and over the upper lateral wall. There is no known connection by which the trunk of the olfactory nerve can be reached by adjustment but the condition of the special end organs in the membrane and their ability to functionate depend not only upon the integrity of their axons but also upon the nutrition and moisture of the membrane in which they are embedded. This is under the control of the Vidian nerve and of branches from the spheno-palatine, or Meckel’s ganglion, both connected with the carotid plexus of the sympathetic and therefore responsive to adjustment of C 2, 3, or 4. This is also the route by which epistaxis is usually checked.

The external nasal muscles, like those of the rest of the face except some of the muscles of mastication, get their supply from the facial nerve, which connects with the sympathetic plexus on the middle meningeal artery. It may be said parenthetically here that peripheral facial paralysis (Bell’s palsy) yields to adjustment and proves the value of this connection. The nasal integument is under the sensor control of the trigeminal and trophic disturbances may result from its involvement.

Trigeminal Nerve: This is the great sensor nerve of the face and carries a motor division, the inferior maxillary, to some of the muscles of mastication, as the temporal, masseter, and buccinator. It has connected with it four ganglia, which also receive sympathetic roots, and the ganglion of origin of its sensor axons, the Gasserian or semilunar, also receives direct sympathetic communications. The importance of this communication is shown by the powerful effect of adjustment of third or fourth Cervical for tic dolouroux.

Ear: The external ear receives branches from the vagus and from the first and second cervical nerves. The middle ear and Eustachian tube are supplied by the tympanic plexus made up of branches from the glosso-pharyngeal, otic ganglion, facial nerve and the small deep petrosal from the sympathetic on the carotid artery. By all these routes communication from the third and fourth cervicals is possible but especially is the latter important. The fourth cervical is the especially frequent subluxation with middle ear disease. To the internal ear and auditory or acoustic nerve there appears to be no direct route from the spine. It has not yet been conclusively established within the writer’s knowledge that adjustments will affect auditory deafness but Meniere’s Disease, inflammation of the semicircular canals, has been cured repeatedly by adjustments of Atlas or Axis, by what route I am unable to state.

Teeth and Gums: It is probable that the only connection between the vertebrae and the teeth is an afferent one by way of the trigeminal. Toothache may be stopped by adjustment of C 3, or C 4, but no evidence is at hand to show that the condition of the teeth is improved or that more than a temporary effect can be had. Trophic changes in the gums may be due to vascular disturbances controlled by the sympathetic.

Tongue: The hypoglossal, motor nerve to both the intrinsic and extrinsic muscles of the tongue, receives direct axons from the loop between the first and second Cervical nerves. Sympathetic fibres pass to the blood-vessels and secreting glands of the tongue.