This is Chapter 3 from RC’s best-selling book:
“Basic Chiropractic Procedural Manual”

Chapter 3: Orthopedic and Neurologic Procedures in Chiropractic

This chapter presents the general diagnostic methods currently used in differential diagnosis of selected orthopedic and neurologic conditions.

Overview

The typical patient presents the challenge of differential diagnosis of a number of neurologic conditions. These range from a variety of peripheral neuritides that may be completely reversible to serious degenerations of the central nervous system.

The tendency of the geriatric patient to develop neurologic problems is often related to the aging process: loss of tissue elasticity, particularly that of the musculoskeletal system. This is manifested by greater rigidity of the spinal column with the appearance of fixation subluxations. These, together with dehydration and subsequent thinning of the intervertebral discs, predispose to radiculitis, neuritis, and vasomotor disturbances and metabolic effects on the cord and brain. The neurologic disturbances can be superimposed on already degenerating arteriosclerotic vessels and alter metabolism of the gastrointestinal and other systems, which may cause serious problems unless recognized early and prompt corrective measures are administered.


Types of Neuritides

      Peripheral Neuritis

Peripheral neuritis is a general peripheral neuritis such as that which may be present in such disorders as diabetes, anemia, and vitamin deficiency. Diminution of all sensation will be noted, with proprioception affected most. A stocking distribution with an ill-defined border is commonly witnessed. Glove distribution may appear later, along with paresthesias in the distal areas of sensory distribution. The clinical picture does not conform to either dermatome or nerve patterns of distribution. The cause for this is unknown.

      Local Neuritis

Acute.   Pain and hyperalgesia are witnessed in the area of nerve distribution, along with tenderness on palpation of the nerve trunk and muscles supplied by the nerve. One or more trigger points may be found. Reflexes are either unaffected or possibly increased.

Chronic.   Paresthesias are reported over the area of nerve distribution, along with tenderness over nerve fibers and muscles supplied by the involved nerve. Hypoesthesia and hypoalgesia are usually present. Diminished reflexes and motor weakness of muscles supplied by affected nerve are typical.

Radiculitis.   Paresthesia and sensory changes are witnessed similar to those present in neuritis, but the area affected corresponds to the dermatome, myotome, or sclerotome of affected roots. Coughing, straining, jugular compression, and other causes of increased cerebral spinal fluid pressure increase symptoms. In chronic cases, there may be paresis of muscles partly supplied by the affected root but not overt paralysis.

      Disassociated Anesthesias in Cord Lesions

Unilateral partial loss of sensation requires complete sensory evaluation of the area of complaint and contralateral side. For example, loss of proprioception in one leg with retention of pain, temperature, and light touch sensation in the same leg, but loss of pain, temperature, and light touch sensation with retention of proprioception in the opposite leg can only occur with an unilateral cord lesion. A classic example is seen in the Brown-Sequard syndrome of hemisection of the cord. This is the result of interruption of the gracilis pathway that runs ipsilateral in the cord and interruption of the spinothalamic tract that lies contralateral in the cord. Other patterns of disassociated anesthesias from cord lesions include:

Syringomyelia.   The typical signs are a shawl loss of pain, temperature, and epicritic sense.

Subacute combined degeneration of the cord.   Bilateral reduction of proprioception and decrease of pain, temperature, and epicritic sense, particularly in the feet and hands are typical, as is a bilateral increase in myotactic reflexes.

Tabes dorsalis.   Bilateral loss of proprioception manifested by locomotor ataxia, and loss of position and vibratory senses with retention of pain, temperature, and light touch are typical.

Cervical Lesions and Cerebral Vasomotor Disturbances

The course of the vertebral arteries through the foramen transversarium and over the arch of the atlas and their frequent inequality of size predispose them to compression and vasomotor disturbances when cervical subluxation exists. Manifestation of cerebral vasomotor disturbances is presented chiefly as alterations of motor function.

      The Pyramidal System

The pyramidal system is composed of upper motor neurons that extend from the motor area of the cerebral cortex through the internal capsule, the basilar parts of the mesencephalon and pons, the pyramid of the medulla where the majority of the fibers decussate to the opposite side, and the posterior portion of the lateral funiculus of the cord. Lesions anywhere along this pathway result in symptoms of an upper motor neuron lesion. These include:

Spastic Paralysis.   The affected part is in firm contraction and efforts to move it are greatly resisted.

Hyperactive Myotactic Reflexes.   These refer to the tendon stretch reflexes in the affected area. The biceps, triceps, quadriceps, or Achilles reflexes are exaggerated when compared with the unaffected side or with the normal when both sides are involved.

Pathologic Reflexes.   These responses appear only with a pyramidal tract lesion. The classical response is the Babinski reflex where the great toe dorsiflexes and the remaining toes fan in abduction when the bottom of the foot is firmly stroked from the heel to the base of the great toe. Similar responses may be elicited by squeezing the Achilles tendon (Schaeffer’s sign), by squeezing the calf muscles (Gordon’s sign), by stroking near the lateral maleolus (Chaddock’s sign), or by stroking downward on the tibia (Oppenheim’s sign). In contrast, lower motor neuron lesions show flaccid paralysis, decreased or absent reflexes, muscle atrophy, and reaction of degeneration appearing in 10–14 days.

      The Extrapyramidal System

Basal ganglia lesions are characterized by hypertonic muscles, rigidity, uncontrolled and involuntary movements, resting tremor, an attitude of flexion, and a festination gait. The rigidity is of the “lead pipe” type where passive movement is resisted but can be achieved. In moving the part, there is a “cog-wheel” effect; and clonus can be demonstrated at the ankle, patella, or wrist, depending on the site of the lesion.

      Cerebellar Lesions

These lesions are characterized by a lack of coordination, an intention tremor, disturbances of equilibrium, and nystagmus. In contrast to most lesions of the brain, cerebellar symptoms are ipsilateral with the lesion. Tests for cerebellar function include Romberg’s, finger-to-finger, finger-to-nose, and heel-to-shin tests, along with rapid pronation and supination of hands, attempting to drum rhythmically on a desk top, and the ability to quickly stop a movement as in Holmes’ rebound phenomenon. Nystagmus, when present, shows the fast component when looking toward the side of the lesion.


Localizing Symptoms and Signs of Intracranial Lesions

      Examination of Cranial Nerves

Olfactory Nerve.   The 1st cranial nerve may be affected by frontal lobe tumors, fracture of the anterior fossa of the skull, pituitary tumors, cerebral vascular accidents, postconcussion syndrome, meningitis, hydrocephalus, drug intoxications, neuroses, psychoses, and congenital defects. Each nostril should be tested separately for ability to recognize familiar odors such as peppermint, menthol, vanilla, cinnamon, coffee, oil of cloves, etc. Avoid use of irritant substances such as ammonia and vinegar. The patient, with eyes shut and one nostril held closed, should be asked to identify the test substances, which are rapidly passed inward from a distance of about a yard from the patient.

Optic Nerve.   After ruling out local ocular causes of disturbance of vision, patterns of visual loss offer one of the best means of locating intracranial lesions when the lesion affects a visual pathway. Tests should always include ophthalmoscopy of both the retina and optic disc. Papilledema appears with increased intracranial pressure. Visual fields: bitemporal hemianopsia indicates a lesion at the optic chiasma. Homonymous contralateral hemianopsia indicates a lesion at the optic tract or optic radiation. Homonymous contralateral quadrantopsia indicates a lesion at the upper or lower area of optic radiation. Complete blindness of one eye indicates a lesion of the optic nerve. For color blindness, test with colored yarn or test cards. For visual acuity testing, a Snellen chart may be used. Jaeger or similar test charts can be used at the bedside. The visual fields may be roughly tested by confrontation. More accurate visual field determination requires the use of a perimeter or tangent screen.

Oculomotor Nerve.   The 3rd cranial nerve supplies all muscles that move the eye except the superior oblique and rectus lateralis. It also supplies the sphincter pupillae and ciliaris muscles. Test eye movements, particularly medial upward and downward. Then test pupillary response to light and accommodation.

Trochlear Nerve.   The 4th cranial nerve supplies only the superior oblique muscle of the eye. Test for ability to move the eye downward and inward. The size and shape of each pupil should be noted. Check consensual light reaction and accommodation-convergence response.

Trigeminal Nerve.   The 5th cranial nerve is the great sensory nerve to the face and the motor supply to the muscles of mastication. Test for usual modalities of sensation over each of the three divisions of the trigeminal. The corneal reflex is tested as the patient looks upward by approaching the cornea from the side and touching it with a strand of cotton. Palpate the masseter and temporalis muscles after the patient is asked to “bite down.”

Abducens Nerve.   The 6th cranial nerve supplies only the rectus lateralis muscle of the eye. Test for ability to move the eye laterally.

Facial Nerve.   The 7th cranial nerve (mixed) is the great motor nerve to the muscles of the face, provides the sense of taste to the anterior 2/3rds of the tongue, and parasympathetic fibers to the mucosa of the nasal cavity and roof of the mouth. Test for action of facial muscles when asking the patient to raise the eyebrows, frown, smile and whistle. For taste, have the patient identify a drop of solution of sugar, salt, vinegar, and alum when each substance is placed on the anterior part of the tongue.

Auditory Nerve.   The 8th cranial is the nerve of hearing and equilibrium. Test the cochlear division for hearing by using a tuning fork. Bone conduction (with base of fork on vertex or occiput) should be equal in both ears. Closing one ear should shift the sound to the closed ear (Weber’s lateralization test). When sound is no longer heard with bone conduction, bringing the fork near the ear without setting it in vibration again, should again be heard by air conduction (Rinne’s test).

Test the vestibular division for symptoms of vertigo, nausea, or disturbance of coordination on the affected side. Nystagmus may be present. A caloric test should be considered. Normally, nystagmus, vertigo, and nausea will appear within 30–40 seconds. A lack of response shows decreased or absent nerve function.

Glossopharyngeal Nerve.   The 9th cranial nerve consist of

(1) sensory fibers from the isthmus faucium, posterior 1/3rd of the tongue, and the pharynx;

(2) motor fibers to the stylopharyngeus muscle; and

(3) parasympathetic fibers to the parotid gland. Test with the gag reflex by touching the posterior part of the tongue or pharyngeal wall.

Vagus Nerve.   The 10th cranial is the motor nerve to the pharynx, uvula, larynx, and upper part of the esophagus; sensory nerve to the pharynx, larynx, and upper esophagus; and parasympathetic nerve to the thoracic and upper abdominal viscera. Test for motor response to the gag reflex and for movement of pharyngeal and laryngeal muscles on phonation. Test the ocuIocardiac reflex.

Spinal Accessory Nerve.   The 11th cranial is the motor nerve to the sternocleidomastoideus and upper trapezius muscles. Test the ability to bring the occiput toward the shoulder (lateral flexion) against resistance and the ability to shrug the shoulders.

Hypoglossal Nerve.   The 12th cranial is the motor nerve to the muscles of the tongue. Test by having patient protrude tongue, The tongue deviates toward the side of paralysis.

      Additional Signs of Intracranial Lesions