Part 30

The frequency with which paraplegia occurs in the large herbivora suggests a special susceptibility of the lumbar portion of the cord, probably in connection with severe muscular effort of the hind limbs.

In protracted cases the fever may run very high, being complicated by septic poisoning from the numerous cutaneous sloughs and sores, as well as by cystitis and nephritis.

Diagnosis. This may be based on the progressive onset, unlike the sudden attack of congestion; on the occurrence of primary fever with hyperæsthesia or even muscular rigidity, merging into a later paresis or paralysis; on the retention of urine, followed by incontinence; on the torpor of the rectum; on the extreme tenderness of the spine in the region of the inflammatory lesion; and on the tendency to rapid atrophy of the affected muscles, and the death and sloughing of the skin under pressure over the prominent parts of the body. The definite localization of the muscular symptoms, and the different temperature and secretion of the affected part of the skin, from the unaffected, are further confirmatory of myelitis.

Prognosis. While always grave, myelitis induced by narcotic elements in the food which can quickly be eliminated from the system, and that which has not caused compulsory decubitus, or persistent retention of urine and fæces, may be considered as hopeful. When, on the other hand, the nature and extent of the lesions have entailed a prolonged paralysis, or in the large animals, (especially solipeds), a persistently recumbent position, there is little to be hoped for. The degenerated myel, and the badly wasted muscles, combine to prevent rising and the use of the limbs, the sloughing bed sores quickly poison the blood and general system, and the animal sinks beyond hope of remedy. Again, if the fæces accumulate in the rectum causing general retention of the bowel contents and fermentation, the shock to the nervous system and the toxins absorbed add materially to the prostration and danger. Finally the retained urine infected through the blood or by a catheter, quickly passes into ammoniacal fermentation, with softening and detachment of the cystic epithelium, septic infection of the mucosa, and the extension of this infection through the ureters of the kidneys. The complication of infective inflammation of bladder and kidneys introduces one of the most dangerous conditions possible.

Treatment. In an acute case, at the outset, elimination of any extraneous poison should be sought as the first step toward a restoration of the normal spinal functions. Purgatives may be employed to this end, and if the case is urgent and without spasms immediate action may be sought by a hypodermic injection of 1½ gr. eserine and 2 grs. of pilocarpin. Meanwhile the horse may receive a dose of aloes or the cow one of Epsom salts. Abundance of watery or demulcent liquids given by the mouth, or as enemas, should not be omitted.

When plethora has been a prominent factor and symptoms are urgent, a free bleeding (4 to 5 quarts for horse or cow) from the jugular vein may serve to relieve the vascular tension, dilute the vital fluid, and moderate the inflammation. Hot fomentations or sinapisms to the limbs, and even cupping on the neck and chest, may contribute to relieve the tension on the spine. When the temperature is already high, bags of ice may be applied to the tender parts of the spine or those indicated to be the inflamed parts by the groups of rigid or paretic muscles. Wet compresses or evaporating lotions may be substituted. In the absence of mustard, tartar emetic, biniodide of mercury, or euphorbium may be used, or even croton oil in a carefully guarded manner, but cantharides, oil of turpentine, and other agents calculated to irritate the kidneys are to be avoided.

Bromides, hydrobromic acid, potassium iodide, chloral, or belladonna may be availed of. Some prefer ergot, but this, like strychnia, is of doubtful effect or positively injurious in most cases in the early stages. Even in the early stages electricity may be used in the form of a constant current, which tends to vaso-motor contraction and a better tone of the capillaries. The electrodes may be applied along the affected side of the spine so that the current may traverse the affected part. It may be kept up for ten to twenty minutes at a time and repeated daily. Any undue suffering under the current may be accepted as a demand for the reduction of its force or its suspension for the time being.

When the hyperthermia has subsided and the occurrence of paresis or paralysis demands nervous stimuli, these may be sought in counter-irritants, strychnia, and interrupted currents of electricity. The blisters already mentioned may be used. Strychnia may be used internally (horse or ox 2 grs., sheep ¼ gr., dog ¹⁄₅₀ to ¹⁄₁₆ gr.) or hypodermically (horse 1½ gr., sheep ⅛ gr., dog ¹⁄₁₀₀ to ¹⁄₃₀ gr.). Should this excite the animal or aggravate the symptoms it must be stopped and deferred until the inflammation shall have more completely subsided. The same remark applies to electricity which may be tried in the interrupted current, and graduated to the endurance of the patient or entirely abandoned for the time.

If the patient is able to support itself on its limbs, it is best kept in a sling to avoid the formation of sloughs and sores. If it cannot so support itself a very thick soft bed of litter is essential to avoid the sloughing and septic poisoning. Food must be laxative and easily digestible such as mashes, hay tea, and boiled or pulped roots. Fresh green grass may be employed when obtainable.

During convalescence a course of bitters with calcium phosphate and carefully regulated exercise are important. In tardy cases Trasbot especially recommends cauterization.

SPINAL MENINGITIS.

Complex cases. Microbian invasion. Lowered vital tone. Traumas. Poisons, parasites, tubercle, rheumatism, neoplasms, poisonous food. Symptoms: Stiffness, tonic contraction, spasms, hyperæsthesia with warmth, enuresis, paralysis later. Treatment: parallel to myelitis; cold, anodynes, nerve sedatives, and antispasmodics, saline purgatives, diuretics. Iodine, electricity, cauterization.

It is often difficult to distinguish between spinal myelitis and meningitis in the lower animals, and the danger of confusion is greater because the two affections are often conjoined. Attacks appear to be often associated with microbian invasion of the membranes, but in its turn this is often favored by the lowered tone of the membranes through mechanical injury, circulatory disorder, trophic changes, or the action of poisons in the blood. Thus the condition may supervene on fractures, partial dislocations or sprains of the neck, back or loins, abscesses pressing on the spine, extension of septic inflammation from poll evil, fistulous withers, or arthritis of the vertebræ, penetration of the membranes by sharp pointed bodies (Reindl found a darning needle in a cow’s spinal canal), invasion by microbes in influenza, brust-seuche, dourine, rabies, milk sickness, distemper, pyæmia, septicæmia, strangles, louping ill, or Texas fever. The toxins of tetanus may start similar trouble. The larva of cysticercus cellulosa may cause meningitis in dogs or pigs, the sclerostoma in the soliped, the filaria in dogs and strongle in a variety of animals. Tubercle of the meninges is not unknown, and rheumatism is alleged as a cause. Neoplasms commencing in the cord act in a similar way, and the poisons of rye grass, millet, loco, lupins, tares and vetches may act on the membranes as well as on the myel.

Symptoms. In the main these resemble those of myelitis and are often present at the same time, and it is only necessary to note those which are especially pathognomonic. The early rigors are followed by stiffness of the back shown in rising or walking and aggravated by motion. There may be tonic contraction of the dorsal and lumbar muscles amounting at times to oposthotonos. The muscles of the limbs, chest or abdomen or some part of them may be the seat of tonic or clonic spasm. The skin is usually hypersensitive and this is aggravated by heat. The urine is liable to be retained because of the pain of stretching to micturate. Paralysis usually follows and implies extension to the myel, compression of the cord by reason of exudation, or implication of the spinal nerves at the points of exit. In myelitis on the other hand the spasms may be entirely absent, and paralysis sets in early and extends rapidly according to the seat and extent of the lesion.

Treatment. This will be along the same lines as in myelitis, being aimed at elimination of toxic matters, and the counteracting of the existing inflammation. Anodynes such as bromides and chloral and cold water or ice are especially called for to alleviate pain and hyperæsthesia, and antispasmodics like ether, chloroform, chloral, belladonna, etc., to allay the spasm. Saline purgatives too, and diuretics may be availed of to limit effusion and favor reabsorption. In the advanced stages iodine may be freely applied to the spine, and an occasional electric current, or cauterization may be availed of.

ACUTE MYELITIS IN THE DOG. MENINGO-MYELITIS.

Causes: distemper, in long-haired pets, pyæmia, exposure to cold, violent overexertion, traumas, vertebral caries or abscess. Lesions: in lumbar enlargement, horns yellowish, red, friable, pultaceous, leucocytes in excess, punctiform extravasations, neurons opaque; granular, filaments diffluent, varicose, sclerosis. Meninges congested, thickened. Symptoms: as in horse, extreme hyperæsthesia, later anæsthesia, tremors or twitching, later paraplegia. Treatment: Laxatives, ice bags, sedatives, later derivatives, cauterization. During convalescence, phosphates, iron, zinc, strychnia. Attend to bladder and rectum, light, laxative diet, pure air and water.

Causes. This disease is a common result of distemper and according to Trasbot, is much more frequent in long-haired and pet dogs than in the short-haired and mongrels. The shelter of the hair, like the warm indoor atmosphere, seems to contribute to a special sensitiveness of the cutaneous and nervous tissues. The infective inflammation of the myel is also seen in pyæmia, rabies and milk sickness. It appears to be further induced by exposure to cold draughts when heated, or excited, by plunging into ice cold water, by lying on cold, damp, stone pavement or metallic plates. Violent overexertion, excessive fatigue, and a variety of traumatisms are further factors. Kicks, blows on the back, concussion from falling from a window or other height, and sprains received in fighting or otherwise, are common causes. Disease of the vertebræ or abscesses in their vicinity will sometimes extend to the meninges and cord.

Lesions. These are like those in the larger animals, being to a large extent determined by the cause and nature of the lesion, concussion, sprain, fracture, pyæmic, septicæmic, or other infection. The implication of the myel to the exclusion of the meninges is very frequent and the lumbar enlargement is the most common seat of disease. Localization in the brachial enlargement or in one lateral half of the cord is uncommon. The gray matter towards the extremity of the horn is the most commonly involved, reflecting a yellowish, grayish red or deep red color, and breaking down into a pultaceous mass on the slightest pressure. At an advanced stage the altered coloring matter gives to the tissue a brownish yellow color without altering its consistency. The still vital and vascular area around the centre of softening may be slightly swollen and abnormally firm. The neuroglia is the seat of leucocytosis, and minute (usually punctiform) extravasations of blood. The red globules are crenated or otherwise distorted and the white are granular and opaque. The neurons are swollen, granular and opaque and the nerve fibres are more or less diffluent, moniliform and in their substance show no clear outline of white substance and axis cylinder. Interruptions by granule masses and vacuoles are common. In old standing or chronic cases the liquid exudate and granular debris have been largely absorbed and the thickening of the neuroglia by fibrous neoplasm, has restored the firmness or even approximated the part to a condition of sclerosis.

In case the meninges are involved there is thickening by exudation into their substance or on their surface, there may be adhesion between the outer and inner layers of the arachnoid and a serous fluid, red, milky or clear, distends the arachnoid or subarachnoid space. The false membranes, here as elsewhere, are usually red if recent, and increase in pallor with age.

Symptoms. These are in the main the same as in the larger animals. The early excitement usually takes the form of hyperæsthesia. When lifted, pressed, touched or only approached the dog may growl, howl, snap, cringe, cower or tremble, glancing up meanwhile with anxious or pleading eyes. When later, this gives place to anæsthesia no such interference will draw a response. The motor disorders at the outset are mostly of the nature of tremors or twitching of the muscles of the limbs or of those parts of the trunk corresponding to the seat of the lesion. In exceptional cases spasms or convulsions may be shown. Trasbot records a case of very acute myelitis of the brachial enlargement in which there were clonic contractions of the muscles of the neck, jaws and eyeballs, and grinding of the teeth, which condition lasted for thirty-six hours. When this motor excitement merges into paralysis it usually attacks the hind limbs which are extended backward helpless while the animal pulls himself forward by his fore limbs. Some such cases are restless and in continual movement while others are dull, apathetic and indisposed to move. The precise seat of the paresis or paralysis will be determined by the seat of the lesion as in the larger animals. Thus paraplegia is most common, less frequently hemiplegia, palsy of the fore limb, palsy of a single limb, and monoplegias, about in the order named. Palsy of the tail and sphincters implies a lesion of the lumbar section of the cord and is very offensive in the incontinence of urine and fæces especially in long-haired subjects.

Treatment. The abstraction of blood is rarely called for in myelitis in the dog. If admissible at all it is in the case of strong, vigorous, plethoric animals which have been attacked in connection with sudden exposure to cold or accidental concussion, and which are presented for treatment at once. Then leeches may be applied to the abdomen or inside of the thigh, or the jugular may be opened with a lancet. Usually on the other hand the patient is fat, lymphatic, and, if a few days have elapsed, even anæmic, while if he has been the victim of an accident the shock and prostration would forbid any depressive measures.

Derivation toward the bowels may be sought by purgative doses of calomel or jalap. In case of high fever, cold may be applied (in the form of icebags, evaporating lotions or wet cloths) to the tender portion of the spine. If the attack has followed exposure to cold, salicylate of soda may be given, otherwise the bromide of potassium or camphor. Acetanilid and other antithermic agents may be used with caution.

With the abatement of the high fever and the supervention of paresis, if not before, counter-irritants are demanded.

Owing to the propensity to lick and the danger of absorption, poisonous agents are virtually proscribed. Yet Möller advises cantharides, croton oil, mercuric iodide, and oil of mustard, and Trasbot restricts the choice to tartar emetic one part to sixteen parts of lard. This the latter rubs softly along the spine for several minutes. If the dog is closely watched or muzzled this or the mustard or croton oil may be admissible. If otherwise, a long-haired dog may be rubbed on the spine with a combination in equal parts of strong aqua ammonia and olive oil; or it may have applied for some minutes wet cloths rather hotter than the hands can bear; or a light cauterization may be made with a Paquelin cautery. At this stage, too, bitters and phosphate of lime may be given. Trasbot has long used with the best results 1 grain doses of neutral, gelatinoid phosphate of lime, repeated two or three times a day. Iron may also be resorted to, or sulphate of zinc. Strychnia and electricity are also of great value as soon as the irritability of the spinal centres will allow of their safe employment. Massage and gentle exercise are important.

From the first, attention must be given to obviate the retention of urine and fæces, and the strict antisepsis or asepsis of the catheter adopted to prevent infective cystitis and nephritis.

Throughout the disease abundant nourishment of an easily digestible quality is demanded. Cleanliness, pure air and general comfort must not be forgotten.

CHRONIC MYELITIS. SCLEROSIS.