Compression of the Spinal Cord.

What are the clinical symptoms of spinal compression ? First, is there any deformity of the spine ? Deformity is very common in caries, but rare in tumour. Neither of these patients had any deformity. Root-symptoms are, almost always, present from the start. If it is a posterior root which is compressed, there is root-anaesthesia at the level of the lesion. If an anterior root is compressed, there is root-atrophy of the muscles at the level of the lesion. There is also loss of reflexes at the level of the root affected. In the first of our two cases the patient had loss of the knee-jerks at the level of the lesion, the third lumbar. Then there are tract symptoms, which may be sensory or motor. What are the sensory tract symptoms ? If the compression is a unilateral affair, you get one set of symptoms; if it is a bilateral affair, you get another set. Suppose it is a unilateral compression of the cord, then you have the Brown-Sequard syndrome-that is to say, on the side of the lesion, pyramidal symptoms below the lesion, and on the opposite side loss to temperature and pain in the opposite leg. There is, in fact, a weak motor leg and a weak sensory leg. If it is a bilateral lesion, what do you get ? You get loss to temperature and pain on both sides from affection of the lateral columns, and if the posterior columns are also compressed-as they were in one of our cases-there is also loss of joint-sense and vibration-sense, the fibres for which run upwards in the posterior columns, and may be spared it. au ordinary Brown-S6quard case. And if the whole tranverse area of the spinal cord is affected, you also get loss of perception of cotton-wool touches. Cotton-wool touch sensations have a choice of two paths: they may take the narrow path in the posterior column of the same side, or the broad path in the lateral column of the opposite side. Therefore both those paths must be obstructed for there to be loss to perception of cotton-wool touches. Remember, also, that the level of the ansesthesia in a completely transverse case is often lower than at first you might expect it to be. This is because of the obliquity with which the spino-thalamic tract crosses over from the posterior cornu to the opposite lateral column. What are the pyramidal symptoms ? If it is a unilateral case, there is motor paralysis below the level of the lesion, with increased tendon reflexes, and an extensor plantar reflex on the affected side. If it is a bilateral lesion, both legs are the subject of spastic paralysis, with increased reflexes, double ankle-clonus, and extensor responses. If it is higher up, there will be paralysis of the abdominal muscles; if higher up still, at or above the upper thoracic region, there will be intercostal paralysis ; and if higher still, in the upper cervical region, spastic paralysis of the upper limbs. It all depends on the level of the lesion. What changes in the reflexes do you expect T The reflexes at the actual level of the lesion of the affected root are absent. In our first case the knee-jerks were absent at the level of the lesion, the third lumbar. Below the level of the lesion the deep reflexes are increased and the plantar reflexes are extensor in type. If the lesion is high enough up, the abdominal reflexes are also absent. With regard to the cerebro-spinal fluid, as I have said, there may be xanthochromia and an excess of albumin which may be so great as to causespontaneous coagulation of the fluid. Sometimes there is also an excess of lymphocytes in the fluid. There is another point about the cerebro-spinal fluid--viz., that the fluid during lumbar puncture no longer pulsates, as it does above the level of the lesion. If you put a needle into the cistern and attach a manometer, you will see the fluid pulsate at each beat of the heart. If you put it in below the level of the lesion, the fluid does not pulsate. Moreover, it is underdecreased pressure. Again, if you inject air into the lumbar region, below the lesion, it will ascend to the lower level of the obstruction and stick there, so that it can be seen by X rays. Better still, if you inject lipiodol (which is an opaque iodised oil) into the cistern, and let it run down within the theca, the heavy oil will drop down to the level of the obstruction and stay there. It was so in both these cases.. Or again, if you put lipiodol into the lumbar region and stand the patient on his head, it will go up to the level of obstruction and stick there, instead of running up into his brain. So you can employ lipiodol to determine the upper and lower levels of the lesion. X rays also show us any bony deformity which may be present, as in caries, and, and in some cases of tumour of the bones. It will always show us the shadow of the lipiodol. In health the lipiodol should fall straight down to the second sacra) segment and form a triangular pool there; but in spinal compression it will be held up at the level of the lesion. These clinical symptoms are so easy nowadays that no one has any difficulty in localising spinal compression, andthe exact level of that compression.