=Olfactory Nerves.=—This nerve may be affected at various points from
its origin to distribution. The disturbances may produce hyperosmia, or
anosmia. The lesions may be tumors, injuries to the head and various
diseases of the brain, or diseases of the nasal mucous membrane.
The =treatment= of the nerve (beside treating the disease causing the
disturbance) is to the cervical region with a view to controlling the
blood supply.
=Optic Nerve and Tract.=[116]—The retina, optic nerve, chiasma and
optic tract may be affected by various lesions.
The affections of the =retina= are organic or functional. Under organic
there is hemorrhage and retinitis. Retinitis may be due to several
diseases, as syphilis, Bright’s disease, anemia, etc., Functional
includes toxic and hysterical amaurosis, tobacco amblyopia, nyctalopia,
hemeralopia and retinal hyperesthesia.
Included in the lesions of the =optic nerve=, are optic neuritis and
optic atrophy.
Under lesions of the =chiasma= and =tract= are diseases of the chiasma
and unilateral regions of the tract. Lesions of the tract and centers
may be found in the tract itself, in the optic thalamus and the
tubercula quadrigemina, in the fibers of the optic radiation, in the
cuneus, and in the angular gyrus.
A brief summary, only, has been given of the lesions found, it being
the idea not to dwell upon symptoms, morbid conditions, etc., but to
bring out essential osteopathic features in regard to the cranial
nerves. For the various effects of these lesions and points of
diagnosis, the reader is referred to the various works on nervous
diseases.
=Lesions= peculiar to =osteopathic= practice, that affect the optic
nerve and tract, are found chiefly in the upper and middle cervical
vertebræ. The disorders to these vertebræ may involve fibers of the
optic nerve directly—those that are supposed to originate in the
cervical spine; they involve the retina and optic nerve by way of the
fifth, as claimed by some; and the above lesions especially affect
the blood supply to the optic nerve and tract, either interfering
mechanically with the blood-vessels or obstructing and irritating
vasomotor nerves. The most common lesions are subdislocations of one or
all of the three upper cervical vertebræ. Still, lesions may be located
as low as the third or fourth dorsal vertebra, which may influence
vasomotor and sympathetic nerves, or the lymphatics. The three or four
upper ribs should also receive due consideration.
=Motor Oculi.=—Lesions of the third nerve may affect its center or the
course of the nerve. These lesions produce spasms or paralysis.
The only way that we can control the motor oculi is by way of the
superior cervical sympathetic; also, it has a connection with the
fourth, fifth and sixth nerves, and we can influence it to some extent
by direct treatment to the eyeball and orbital muscles. It should be
remembered by the osteopath that many of the lesions affecting the
cranial nerves, are found upon post-mortem examination, to be the
effect of lesions in the spinal region; that many predisposing lesions
are the disordered anatomical spinal tissues; as for instance in the
third nerve, derangements of the atlas or axis may affect the nerve
sympathetically (reflexly), or possibly by direct fibers, and produce
the secondary effect—the so-called primary lesions of other schools—at
the center or in the course of the nerve.
=Patheticus.=—This nerve may be involved by tumors at its nucleus,
or as it passes around the outer surface of the crus into the orbit.
Aneurisms or the exudation of meningitis may also compress its fibers.
This nerve is purely motor, although it receives a few recurrent
sensory fibers from the fifth nerve.
This nerve is controlled osteopathically, principally at the superior
cervical sympathetic. It has connections with the sympathetic by way of
the cavernous plexus.
=Trigeminus.=—Lesions of this nerve are found in its nucleus and in
the pons, and include sclerosis, hemorrhage, disease and injury at the
base of the skull, tumors, aneurisms, inflammation of the nerve, and
subdislocations of the =upper three cervical= vertebræ, or the inferior
maxillary.
This nerve is an extremely important one from an osteopathic point
of view, as it has a vasomotor influence over various vessels of the
head and face, and secretory fibers to the lachrymal, parotid and
submaxillary glands; also, it controls mastication, and to some extent
deglutition, and influences hearing (tensor tympanum muscle). Diseases
of the nasal mucous membrane and disease of the anterior portion of
the eyeballs are largely due to the =vertebral subdislocations= and
to derangements to the inferior maxilla. Our principal work upon this
nerve is at the upper cervical vertebræ, the inferior maxilla, and the
deeply contracted muscles in the upper cervical region. For the facial
points of treatment =see neuralgia of the fifth nerve=. This nerve is
closely related to the sixth, seventh, eighth, ninth, tenth, eleventh
and twelfth nerves. Particular emphasis is given to the importance
of treating this nerve in nasal catarrh and in eye diseases of the
anterior portion of the eyeball. It contains trophic fibers to the eye,
sensory fibers to the sclerotic coat and iris, and vasomotor fibers to
the choroid plexus.
=Abducens.=—This nerve is especially liable to be affected by tumors
and meningitis. It is controlled osteopathically at the superior
cervical sympathetic, being connected with the sympathetic at the
cavernous plexus.
=Facial.=—Lesions may occur in the cortical centers of the nerve, the
nucleus and the nerve trunk. Paralysis of the facial nerve occasionally
occurs (Bell’s paralysis); also facial spasm may occur. This nerve
is controlled at the stylomastoid foramen. =Lesions= to the =atlas=,
anteriorly or laterally, are commonly found. In the region of the
stylomastoid foramen, the nerve communicates with the great auricular
of the cervical plexus, the trifacial, the vagi, the glosso-pharyngeal
and the carotid plexus of the sympathetic. The facial nerve may be
affected directly as it passes above the angle of the jaw.
Nearly every case of =Bell’s paralysis= can be cured by osteopathic
treatment. There are usually lesions to the upper two or three
cervicals. Correction of the cervical vertebræ and massage of the
paralyzed muscles, with care of the general health, will suffice,
provided there is not an extensive central lesion. Although the
disease may be due to syphilis, meningitis, tumors, etc., the most
frequent causes are lesions of the =atlas=, =axis=, and =third
cervical= and =exposure= to =cold=. The cold produces a neuritis in the
Fallopian canal, and deep treatment beneath the angle of the jaw is
effective. The =prognosis= of Bell’s paralysis is favorable.
=Auditory.=—Lesions[117] affecting this nerve may occur anywhere from
its cortical center to its distribution in the cochlea and vestibule.
Disorders resulting from lesions to this nerve are nervous deafness,
auditory hyperesthesia, tinnitus aurium, and Meniere’s[118] disease.
The control of the nerve and the treatment of lesions affecting it, are
effected principally at the =first= and =second cervical= vertebræ.
The atlas is especially apt to be subdislocated anteriorly or in a
rotary manner. The condition of the =upper dorsal= region should also
be carefully examined, as vasomotor nerves to the ear may be impinged
at this point. The auditory connects with the fifth, sixth and seventh
nerves.
=Glosso-Pharyngeal.=—This nerve may be affected by tumors,
degenerations, meningitis and various lesions. It is often very hard to
determine exactly the pathology, on account of its various connections
with other nerves, the vagi, facial, spinal accessory, olfactory and
optic nerves.
This nerve is chiefly controlled at its exit at the jugular foramen.
Osteopathically, =lesions= of the =cervical= vertebræ and =upper
dorsal= vertebræ affect it. The deep muscles of the anterior and
lateral regions of the neck and subdislocations of the atlas especially
affect the nerve.
=Pneumogastric.=—On account of its extensive distribution, and the
importance of its functions this is one of the most important nerves
in the body. It distributes fibers to five vital organs—heart, lungs,
stomach, liver and intestines—and to other organs of secondary
importance. This nerve is associated with deglutition, phonation,
respiration, circulation and digestion.
Hemorrhages, softening, etc., may involve the nucleus of the nerve,
while the trunk may be impinged by tumors, thickened meninges, aneurism
of the vertebral artery and =subdislocation= of the =upper five= or
=six cervical= vertebræ, chiefly the atlas.
The nerve is most easily controlled at its exit from the foramen.
Inhibition of the suboccipital region, between the mastoid process
and transverse process of the atlas, will influence the nerve
markedly, probably reflexly; also direct treatment may be given
the nerve as it passes along the anterior part of the neck near the
trachea. The superior laryngeal branch may be treated below the
great cornu of the hyoid bone and attention is particularly called
to this in all affections of the throat where coughing is a feature;
the inferior laryngeal, at the inner side of the lower part of the
sternocleidomastoid muscle. The inferior laryngeal nerve may be
affected by dislocation of the first and second ribs, producing
pressure upon the nerve as it winds about the subclavian vessel. Fibers
of the nerve have been traced to the spinal accessory nerve, as low as
the sixth and seventh cervical vertebræ; consequently, lesions to the
vagi nerves may occur anywhere in the cervical region.
=Spinal Accessory.=—Lesions of this nerve may cause paralysis or spasms
to the structures to which it is distributed. The lesions consist of
=subdislocations= of =cervical= vertebræ, chiefly the upper three or
four. The nucleus may be involved by wounds, abscesses, caries of the
vertebræ, tumors and meningitis. These lesions may also involve fibers
of the trunk.
The special points of control of the nerve are at the jugular foramen,
the sixth and seventh cervicals and the second, third and fourth
cervicals.
=Torticollis= or =Wry-neck= is spasm of the muscles of the neck
supplied principally by this nerve. There will be found either
derangements of the =middle= or =lower cervical= vertebræ or the
muscles are swollen from exposure to cold or from a blow. Sometimes the
lesion is in the upper dorsal. The disorder is mainly a neurosis and,
unless it has become chronic, the =prognosis= is favorable, and even in
chronic cases, often considerable benefit can be obtained.
=Hypoglossal.=—This nerve may be affected by cortical, nuclear and
infra-nuclear diseases, as well as by subdislocations of the upper
cervical vertebræ. It communicates with the superior cervical ganglion,
the vagi, the upper cervical nerves and the gustatory branch of the
fifth nerve. We control the nerve at the anterior condyloid foramen and
at the superior cervical ganglion.