absence of such symptoms has incomparable less significance than their presence.

The symptoms of meningeal hæmorrhage, in acute cases, usually reach their height in two or three hours, but sometimes not for a few days. Death may occur when the effects are fully developed; or, after the symptoms have reached their height, they may decline, to be renewed, a day or two later, by secondary meningitis. This is accompanied by some pyrexia, and may cause death; but if moderate, the symptoms of inflammation last a week or ten days, and then, in favorable cases, permanent improvement commences.

The period of the disease at which death is most common is a few hours after the onset of the symptoms. It may be due to exhaustion, in consequence of the violence of the pain and spasm, but is more often caused by the interference with respiration that results from the conjoined effect of the palsy and spasm.

DIAGNOSIS.-In cases in which definite symptoms are produced, the diagnosis rests on the combination of sudden local pain in the back, with the other evidence of irritation of the membranes, nerveroots, and cord, above enumerated. When the hæmorrhage is of traumatic origin, the fact that the symptoms rapidly followed an injury facilitates the diagnosis. In the extremely rare cases in which the symptoms come on insidiously, without pain, the diagnosis of the exact nature of the disease is scarcely possible.

In hæmorrhage into the substance of the cord, vertebral pain is much more frequently absent than in meningeal hæmorrhage, and when it occurs is less intense and does not spread. The symptoms of injury to the cord itself are prominent from the commencement; there is sudden paralysis, it may be at first partial, and rapidly increasing; even if there is some spinal pain at the onset, the loss of power is soon recognised, not being concealed either by the severity of the pain or by spasm. In meningeal hæmorrhage, severe pain and symptoms of irritation usually precede considerable paralysis. In cases which recover, the paralytic symptoms are more persistent when the hæmorrhage is into the substance of the cord. But hæmorrhage into the cord often breaks through into the membranes, and the symptoms of both lesions are then combined.

Meningitis is distinguished by the more gradual onset of the symptoms and by the presence of fever from the first; the fact that inflammation results from hæmorrhage must be kept in mind. In myelitis, pain is commonly absent, and the symptoms of irritation are insignificant. The diagnosis from tetanus depends on the absence of trismus, on the presence of severe spinal pains, and on the sudden onset. In newly-born children the diagnosis is supposed to be diffi. cult, but during the first few hours or days the tetanoid symptoms which sometimes occur are the result of meningeal hæmorrhage aud injury to the motor cortex.

One case of spinal hemorrhage has been recorded in which the

symptoms very closely simulated those of strychnine poisoning. Violent paroxysms of muscular spasm, with intense general pain, but without spinal pain, followed by death in two hours, were apparently due to an extensive hæmorrhage into the sac of the dura mater.* Analysis revealed no strychnia in the stomach. In such a case the diagnosis would have to be guided as much by circumstantial evidence as by the symptoms, and even the post-mortem discovery of hæmorrhage could only be received as evidence of the cause of the convulsion if no other were found.

PROGNOSIS.-In all severe cases, death in a few hours is to be feared. The prognosis only becomes less grave when the symptoms have distinctly reached their height, although there is still some danger until the period of secondary inflammation is over. Paralytic symptoms often persist for some time, but even these, in the end, may pass away. At the onset, the prognosis must be governed by the rapidity with which the symptoms develop and by the seat of the disease. Hæmorrhage in the cervical region is especially serious, because the mechanism for breathing is directly involved.

TREATMENT.-The first point to secure is absolute rest. Even passive movement should be avoided. Posture is also of most urgent importance. It should be on the face or side, and not on the back, so that the spine may not be the lowest part. The prone position for a few hours adds greatly to the chances of less damage. Venesection has been employed in strong individuals, with the object of arresting hæmorrhage by rapidly lowering the blood-pressure. Leeches or wet cupping to the spine, or leeches to the anus, have also been recommended in cases in which venesection is unadvisable. It is probable that the local abstraction of blood does more in this than in most internal hæmorrhages, on account of the communication between the venous plexuses and the veins in the retro-vertebral tissues; and it is probable that the wisest treatment at the onset would be scarification beside the spine, opposite the seat of pain, the blood being allowed to flow freely. This may be followed by the application of ice and by the administration of ergotine by the skin or mouth. Afterwards the bowels should be freely opened. Sedatives are usually required to relieve the pain. The stage of meningitis must be treated on the principles laid down for the management of the acute form of that disease. The residual palsy requires treatment by electricity, &c., in the same manner as the consequences of meningitis.

In extra-meningeal hæmorrhage it seems justifiable to remove blood that is compressing the cord, by opening the canal and perhaps even washing out the canal with an astringent and antiseptic solution. Even when the blood is within the dura mater, the operation seems to deserve consideration if life is threatened.

* Dixon, Lancet,' 1879, p. 333.

DISEASES OF THE SPINAL CORD.

ANÆMIA AND HYPEREMIA OF THE SPINAL CORD.

The condition of the vessels of the spinal cord after death, their fulness or emptiness, affords no indication whatever of their state during life. Inferences as to the ante-mortem state, drawn from the post-mortem condition, are altogether erroneous, with the rare exception of local change, in which the vascular condition of one part differs from the rest. Practically, such local variation occurs only as part of a local lesion, as, for instance, in the hyperemia that attends inflammation, and the anæmia that results from pressure. Hence the occurrence of variations in the state of the vessels of the cord, and the effects that such variations may produce, are matters of inference from symptoms observed during life-symptoms that are, in themselves, open to various interpretations. Where the ground is barren of facts, theory is always luxuriant. Anæmia or congestion of the cord affords a ready explanation of symptoms the cause of which is unknown, and it is scarcely surprising, therefore, that such an explanation has been often given. But the extent to which the conditions have been invoked transcends any measure of justification, and surprise cannot but be felt at the absolute confidence and precision of detail with which these states have been assumed to exist, when there has been no tittle of definite evidence. Positive assertions always receive some credence, however unwarranted the assertions may be, and positions incapable of proof are sometimes also incapable of disproof. It would be a futile and useless task to attempt to refute in detail the various statements that have been made regarding the influence of anæmia and hyperemia of the spinal cord. It will be sufficient to point out briefly what may be reasonably surmised regarding these morbid states.

ANEMIA OF THE CORD.

Permanent diminution in the blood-supply to considerable areas of the spinal cord must be a result of the general narrowing of the arteries that has been met with in some cases of chronic meningitis; but it is then associated with structural changes in the organ, the effects of which obscure any symptoms that can be ascribed to the anæmia. Nothing is practically known of the special consequences of this condition. The same statement may be made of the arrest of the blood-supply to limited areas, although it may safely be asserted that loss of function of the part must be a necessary consequence. This has been also demonstrated by experiment. Suddenly produced, anæmia at once abolishes function and quickly causes necrosis of the

nerve-elements-some of which, however, break up less rapidly than others, and retain, for a longer time, the power of resuming function if the blood-supply is restored. It is possible that such local arrest of the circulation is the initial process in some organic lesions of the cord, but the fact has still to be demonstrated. The question of the occurrence of embolism is referred to in a separate section.

Transient diminution in the blood-supply may conceivably be the result of imperfect embolism, but has not been proved to have this origin. It is sometimes supposed to be due to arterial spasm, dependent on the vaso-motor nerves. This has been assumed as an explanation of certain passing symptoms occasionally complained of, loss of power in the legs, and sensory disturbance, tingling, "pins and needles," &c., in the legs and arms. It may possibly also be the cause of the tetanoid cramp and tingling in the hands with which patients sometimes wake up during the night. The theory is tenable, but it is also conceivable that such symptoms are due to transient functional states of the nerve-cells of the cord. A functional derangement of these cells must be the immediate cause of the symptoms, whether such derangement is primary or is produced by spasm of the vessels. The opinion that the "nocturnal tetany" (as it may be called) has the latter origin is supported by the fact that the occurrence of the symptom may be prevented by a small dose of digitalis, taken at bedtime.

The curious symptom known as "intermitting lameness" (which would be better termed "paroxysmal lameness") is supposed to depend on temporary diminution of the blood-supply consequent on arterial degeneration, but it is not known whether the seat of this is the spinal cord or the brain. The character of the symptom suggests the former, but its associations the latter, and it is not known that the arteries of the cord are ever the seat of atheroma in the cases in which this condition causes the cerebral symptom commonly associated with it," dyslexia," a peculiar intermitting difficulty in reading which will be described in vol. ii. The lameness consists in a sudden weakness and stiffness of one leg, accompanied with tingling and blunting of sensibility, and of pain on an attempt to use it. The symptoms are increased by an effort to continue walking, and pass away after a rest of ten minutes or so, usually returning, on renewed exertion, again and again. The difficulty only occurs during exertion. It is familiar to veterinary surgeons as occurring in horses. The dyslexia with which it may be associated is of grave significance, as the cerebral cause seems always to have a strongly progressive character.

In general anæmia, such as occurs in chlorosis and pernicious anæmia, the nutrition and function of all organs suffer, and the spinal cord shares the general state. The readiness with which fatigue of the legs is induced in such conditions may be due to the spinal cord as well as to the muscles. The legs often ache, and are sometimes the seat of various disordered sensations. It is probable that these

are the result of the impaired nutrition of the nerve-elements, in consequence of which their functions are readily deranged. In some patients graver symptoms occur,-weakness of the legs, sometimes of the arms also, which may increase slowly to complete paralysis. Sensation and the sphincters are usually unaffected. The nature of these cases is uncertain. It is probable that many are cases of what is called hysterical paraplegia. Others may be due to organic changes induced by the anæmia. The well-established fact that optic neuritis may result from chlorosis is interesting as proof of the intensity of changes in nerve-structures which anæmia may excite. The cases of chlorotic paraplegia are very rare, and need further study.

In the quantitative anæmia that results from loss of blood, besides the symptoms just described, paraplegia sometimes comes on, under conditions which exclude the idea of hysteria. The source of the hæmorrhage has most frequently been the stomach, kidneys, and uterus. The paralysis is usually motor only, but Leyden has observed accompanying hyperæsthesia. It may come on on a few hours or days after the loss of blood, or only at the end of one or two weeks. Most cases recover. The pathological process which causes the paralysis is not known. The loss of power is comparable to the loss of sight which occurs from the same cause, and in which there may be no visible morbid change, or inflammation may be found, sometimes succeeding the loss of sight, and therefore to be regarded as a result of the derangement of the nerve-elements, or of the influence to which this is due, rather than the cause of the amaurosis.

The treatment of the symptoms due to general anæmia is of course essentially the improvement of the blood-state. Symptoms which can be ascribed, with probability, to vaso-motor spasm may be prevented by drugs that cause a more uniform arterial tone, such as digitalis or belladonna, coupled with nux vomica or strychnia, to render the effect permanent.

HYPERÆMIA OF THE SPINAL CORD.

The conditions of the return of venous blood from the cord probably shield it effectually from the mechanical congestion from which almost every other organ of the body suffers when the movement of blood through the thorax is hindered. The chief mechanical conges

tion to which the cord is liable is that which results from the influence of gravitation, and occurs when a person is lying on the back. The distension of the veins outside the dura mater, and also of those of the pia mater, which occurs when the heart has ceased to act, and the blood is free to obey the only mechanical force which then acts upon it, sufficiently proves the power of gravitation to congest the cord. But it is not probable that gravitation has anything like the same influence during life, counteracted, as it then is, by many other forces.