tion with such different lesions, or independent of any which can be appreciated, that precision of diagnosis seems impossible. Counter-pressure.-Dr. Hall comments on the effects of undue pressure, and of defective pressure. "It is well known from the experiments of M. Flourens especially, that irritation of the cerebrum has no influence in inducing spasmodic action. Whenever, therefore, spasmodic symptoms occur in diseases of the cerebrum, it must as I have already stated, be on a principle different from that of irritation of the substance of the cerebrum itself; it must be from an impression made upon parts of the nervous system in which the property of exciting spasmodic action on being subjected to irritation resides; these parts are the tubercula quadrigemina, the medulla oblongata, the intra-cranial nerves, &c. That undue counter-pressure on the medulla oblongata may, and actually does, excite convulsions, is proved by the following facts: In the interesting case, most anxiously watched and accurately detailed to me by my friend Mr. Toogood, of Bridgewater, of his own little girl, aged thirteen months, the crouplike convulsion occurred repeatedly, until one day, when the bones of the cranium separated, and the convulsion ceased. In a case of spina-bifida, related to me by Mr. Herbert Evans, of Hampstead, there was a croup-like convulsion whenever the little patient turned so as to press upon the tumour. In the case of an anencephalous fœtus, described by Mr. Lawrence, convulsion was produced on pressing on the medulla oblongata. In a case of meningitis, given by Dr. Abercrombie, the anterior fontanelle became very prominent. Pressure upon it induced convulsion. Hypertrophy of the brain affords an argument of the same kind: it induces convulsion, except in the case in which the cranium grows with the encephalon. These and other facts lead me to think that convulsion arising from cerebral disease is thus to be explained." 107. Dr. Hall relates an interesting case from Andral, in which defective pressure was a cause of convulsions likewise. M. Berard removed a fungous tumor from the dura mater-convulsions followed. He applied pressure on the cerebrum, and the convulsions ceased. Dr. Hall concludes, that the true spinal symptoms which occur in cerebral attacks arise from counter-pressure; when the source of this is permanent, as in hemorrhagy, the effect is permanent too, and the case fatal; when it is remediable by blood-letting, as in congestion, the cause and its effects are removed together. The convulsions induced by hæmorrhage depend upon a similar subtraction of the intra-vascular pressure of the blood in the medulla oblongata. But the changes must be rapid. The cerebrum accommodates itself to tardy ones. The next subject to which Dr. Hall passes is : 3. The Special Anatomy of the Base of the Encephalon in reference to Diseases of the Nervous System. After noticing the disposition of the constituents of the basis of the brain, and the effects of the tentorium in preventing direct pressure from the cerebrum on the parts below; Dr. Hall adds : "It is these circumstances, combined with another element of the proposition -that of time-which frequently leads to an effect which I shall notice immedi ately; viz. the difference of symptoms with identity of lesion, and the similarity in the symptoms when the lesion is dissimilar. The same morbid change will produce very different effects, developed as an acute and as a chronic disease; and different physical lesions will produce nearly the same results, if developed in nearly equal times. In a chronic affection, the cerebral substance yields, its vessels becoming empty, and pressure is not induced. In acute affections, on the contrary, pressure is made upon contiguous, and counter-pressure upon distant parts, with their appropriate symptoms. By degrees, even in the latter case, the cerebral substance yields, and the symptoms, in the less severe case, subside, and even disappear." 110. Then comes an important inquiry, viz.— 4. Why, with similar symptoms, have we dissimilar morbid appearances, and vice versa? and, what are the Diseases of the Nervous System, in which we find no morbid appearances on a post-mortem examination? If, observes our author, the source of the symptoms be not the mere lesion of a function, induced by the lesion of a special part or organ of the encephalon, but the effect of irritation and counter-irritation, of pressure and counter-pressure, it is obvious that these primary effects, and their effects in their turn, may result from any disease, if the times be similar, whatever that may be. It is accordingly to the history that we chiefly have recourse for the diagnosis of cerebral diseases, and especially to that of the seizure and first stage at their close, almost all diseases of the encephalon are alike : almost all terminate by coma, paralysis, convulsions, stertor, and impaired actions of ingestion and egestion, and of the orifices and sphincters, from compression of the cerebrum and medulla oblongata. If Dr. Hall implies that different lesions occurring in the same time have the same symptoms, we fear we must hesitate to agree with him. If he contends only that they may have, that is another matter. One case of chronic abscess in the cerebrum may be attended with obstinate vomiting another case of abscess, equally chronic, may never be accompanied by vomiting at all. No doubt, the discrepancies depend on modifications of irritation, pressure, vascularity, &c., but the capability of measuring or determining in diagnosis those seemingly capricious and fugitive conditions, will probably ever be denied to us. ease. Besides, as Dr. Hall remarks, morbid changes take place towards the close of many diseases, which do not properly, or at all constitute the disIn exhaustion, in chlorosis, in delirium tremens, effusion of serum, and even of lymph occurs. In disease of the encephalon itself, such effusion also takes place, late in its course, and complicates the original disease. Effects of Exposure to Severe Cold.-Whilst exposure to a moderate degree of cold conduces to the state of hibernation, a physiological and preservative condition, exposure to intense cold induces torpor, a state totally different, but not sufficiently distinguished from the former, of a pathological character, and of fatal tendency. In the state of hiberna tion, the animal is dormant and motionless, but the actions excited are perfectly regular; in the state of torpor, on the contrary, the animal moves about, but the movements are, in the highest degree, irregular and tottering. This stupor ends in death. In man, the impairment of muscular power, when benumbed by cold, is well known. Exposure to extreme heat or cold equally induces spasmodic action in the muscular system. A young gentleman having been ordered a warm bath, mistook the temperature, and exposed himself to such a degree of heat as induced general spasmodic action of the most painful kind. The effect of too intense a cold on swimmers is familiar. "When the exposure to cold is more partial, effects on both the sentient and motor portions of the nervous system are produced, which have this characteristic-there is at first paralysis, and afterwards undue action. The first effect of exposure to cold is numbness in the fingers; this usually yields to pain, vulgarly termed hot-ache,' especially if the warmth be restored too rapidly. In a relative of mine, exposure to a severe wind, with sleet, induced perfect numbness of one side the face; this paralysis subsided, and gave way to severe tic douloureux. A lady, whose case I shall detail more at length immediately, was exposed to severe cold with wind. The next day she arose from bed with paralysis of one side of the face! This paralysis yielded by degress to spasmodic tic. Exposure to cold is a far more frequent cause of paralysis than is generally supposed. Such an effect on the face has been designated, in common language, (which frequently involves an important truth,) a blight. Cases of paralysis of the face; from exposure to cold, are detailed by Dr. Powell in the fourth volume of the Transactions of the Royal College of Physicians. There is a poor little boy, residing near me, of six years of age, whose limbs are nearly paralytic in consequence of a long and most criminal exposure to cold by a nurse. years ago, I visited a gentleman perfectly paraplegic, from long exposure to intense cold on the outside of a coach. Baron Larrey speaks of permanent paralysis, left by exposure to intense cold during the campaign in Russia. Paralysis, happily of a less permanent character, has been experienced by every one ander similar circumstances. Some But the point to which I must now revert, and to which I beg to call the attention of the members of this Society, is, that the first effect of a partial but severe exposure to cold is paralysis; whilst the more remote effect is undue action." 118. Dr. Hall relates a case in which the face was first drawn to the left side, the right eyelid being paralysed. Afterwards the face was drawn to the right side, the right eyelid being closed spasmodically. He concludes, and probably with truth, that there was first a paralytic condition of the right facial nerve, and afterwards a spasmodic affection of it. From misapprehension of this, the remedies were applied to the wrong side of the face. In conclusion, Dr. Hall recommends that, in all future cases of disease of the nervous system, the various points be observed in the following order. I. The Cerebral Symptoms. No. 87. 1. Excess, or defect, in the Senses; Pain 2. Delirium; Coma. 3. Paralysis. 3 II. The true-Spinal Symptoms. 2. 1. The functions of Ingestion. 2. Temperature. 3. The Secretions, especially those of 2. The Stomach and Intestines. 3. The Kidneys and Bladder. IV. The Effects of Emotion. V. The Effects of Shock. VI. The Effects of Counter-pressure, &c. Like all Dr. Hall's Memoirs highly ingenious. IX.-ON DISLOCATIONS, ESPECIALLY OF THE HIP-JOINT, ACCOMPANIED BY ELONGATION OF THE CAPSULE AND LIGAMENTS. By Edward Stanley, F.R.S. Mr. Stanley's object is to direct attention to the subject of dislocations of the larger joints, and especially of the hip, occurring under other circumstances than as the direct consequence of external violence, or of the destructive processes of inflammation. Mr. Stanley relates seven cases. We will give them as briefly as we can. the CASE 1-Dislocation of both hip-joints, consequent on disease of the spinal cord, and probably of the brain.-A gentleman, aged thirty-nine, in year 1824, was attacked with spasms in the pectoral and intercostal muscles, and numbness in the whole of the left side of the body, with the exception of the arm. In the left thigh and leg, sensation was wholly lost, the power of motion remaining. He had no sensation of passing his urine after it had quitted the bladder, and was but just aware of the evacuation of the fæces. Vision in the left eye was impaired to the extent that he could but distinguish daylight. These symptoms continued, with increasing weakness in the thighs and legs, to the complete loss of the power of support, and of sensation in them. With the impairment of the natural sensibility of the limbs, he occasionally suffered in them the most severe pains, sometimes attended with a smarting sensation, at others, with the sensation of a blow frequently repeated. In March, 1828, he was attacked with violent spasms in his body and limbs, which compelled him to remain in bed several days. On rising from his bed when the spasms had subsided, he found, to his great surprise, his right lower limb so much shortened, that when erect he was but just able to touch the ground with his great toe, and at the same time he remarked a protuberance at the upper and back part of the thigh. In the following December there was a repetition of these occurrences, but in the other limb, an attack of spasms being followed by shortening of it, with a protuberance at the back of the thigh, as on the opposite side. He could still bear the weight of his body upon his limbs, but was almost wholly unable to move them. At no period had there been tenderness, or other sign of inflammation in the soft parts around the hip-joints. In June, 1831, Mr. Stanley noted the following particulars:-The spasms and the attacks of pain are chiefly confined to the chest and to the lower limbs; he suffers a distressing sensation of tightness with acute pain on both sides of the chest, in the direction of the ribs from their angles to the sternum. Movements of the arms excite this pain. Firm pressure by the hands against the walls of the chest greatly relieves it. There is paralysis of the rectus superior muscle of the left eye, and its sensibility to the impression of light is much weakened. In the erect posture there is a remarkable projection at the back of the pelvis, which, upon examination, is ascertained to be caused by the extremities of the thigh-bones occupying this situation. In rotating each thigh, the head of the femur can be felt moving freely beneath the glutei muscles. The trochanter major of each femur is thrown directly backwards. The distance between each trochanter and the head of the bone is natural. The head of each femur thus situated upon the posterior part of the pelvis is two inches and a half below the highest part of the crista of the ilium, and four inches distant from the anterior superior spine of the same bone. In the erect posture, there is a diminution in the stature to the extent of between five and six inches, and evidently from the pelvis sinking between the thighs. In the horizontal posture, the thighs can be readily pulled downward so nearly to their natural situation, that the shortening of the stature is then only to the extent of between one and two inches. At the present time, the extremities of the thigh-bones are not so moveable as they were, apparently from the thickening and consolidation of the surrounding cellular tissue. There has been a gradual recovery of the power of directing the movements of the limbs, which is now sufficient to enable him to walk at a slow pace, with the aid of a stick, Case 2.-Dislocation of the hip-joint consequent on an attack of hemiplegia. A gentleman, aged 48, had been for above eight years affected with hemiplegia, chiefly perceptible in the left lower limb. He had been a courier, and he attributed his complaint to the severity and vicissitudes of weather to which he had been constantly exposed. Two years before his death, it became evident, as he moved about on crutches, that the affected limb had become considerably lengthened; this was accompanied by wasting of the limb, with a remarkable flaccidity of the muscles; and on rotating the thigh, the head of the femur could be so plainly felt, that it was concluded it must be out of its socket. This circumstance gave an interest to the case, which led to a careful examination of the hip-joint after death, when the following peculiarities were noticed: The capsule and the ligamentum teres were entire, but elongated to the extent of allowing the head of the femur to pass beyond the limits of the acetabulum. |