growing rapidly, and whose muscular system is weak, the bad habit of standing, and throwing the weight of the body constantly on one leg, gives rise to a serious tilting of the trunk; or, if, when writing at a desk, they sit habitually in a twisted position, a lateral curvature of the spine is apt to take place. By constant indulgence in these bad habits the spinal column gets permanently set in a faulty position. Sometimes the tilting of the base of the trunk is due to a congenital or acquired difference in the length of the legs. In the concavity of the curve there is increased pressure, and, necessarily, diminished growth; in the convexity of the curve there is diminished pressure with increased growth. The patient's friends probably notice that one shoulder is higher than the other, or that " the hip is growing out," and unless means are taken to alter the abnormal distribution of pressure, the condition becomes worse, until complete ossification checks the further progress of the deformity. The growth of the subject being completed, the deformity ceases to increase. And when the growth is completed and the bones are solid and misshapen the condition is quite incapable of improvement. The usual curvature is one in which there is a convexity of the spine in the chest-region towards the right, with the right shoulder higher than the left. Compensatory curves in the opposite direction form in the loins and neck. Along with the lateral bending of the spine a rotation of the bodies of the vertebrae towards the convexity of the curve takes place, the spinous processes turning towards the concavity of the curve. Since the line of the spinous processes of the vertebrae can be easily traced through the skin, their deviation may mislead the superficial observer as to the actual amount of the curvature.
To counteract this deformity in the earliest stages (and it is in the early stage that treatment effects most), the patient (generally a girl) should be encouraged to walk perfectly erect. Systematic exercises, to strengthen the muscles of the back, ought to be strictly and persistently carried out under the direction of a surgeon with the assistance of a skilled instructor of gymnastics. During the intervals of rest the child should lie upon her back on a firm board, and should avoid taking exercise which gives rise to weariness of the muscles; for whenever the muscles become wearied she will attempt to take up a position which throws the strain on to her ligamentous and bony structures. One of the best exercises is to lay the patient on her face, fix her feet, and encourage her to raise herself by using the muscles of the back. Whilst she hangs from a trapeze the weight of the lower limbs and pelvis will help to straighten the spine as a whole, necessarily diminishing the increased pressure upon the cartilaginous bodies of the vertebrae towards the concavity, and increasing the pressure between the sides of the bodies towards the convexity. It is often a good thing to remove a girl with commencing lateral curvature from the sedentary life of school or town and to let her run wild in the country, exercising her muscles to the full.
If the deformity is due to inequality in the length of the legs, a high boot on the short leg may correct it. In some cases of lateral curvature a tilted seat is useful. Mechanical " spinal supports " are as expensive as they are inefficient. As a rule, indeed, they are positively harmful, in that they add to the weight of the trunk and hinder needful muscular development.
By kyphosis is meant an exaggerated degree of roundness of the shoulders. It can be effaced only by constant drillings and exercises whilst the spinal column is still plastic. When once the bones are solid no great improvement is possible. The deformity is sometimes due to short sight. It is well, therefore, to have the child's vision duly tested.
Lordosis is an exaggeration of the normal concavity of the loin-region of the spine. It is most often met with in those cases in which from congenital displacement of the head of the thigh bone, or from old disease of the hip-joint, the subject has acquired the habit of throwing the shoulders back in order to preserve the balance.
Tuberculous disease of the spine (Pott's disease), is the result of a deposit of tubercle-germs in the body of the vertebra. Inflammation having thus been set up, ulceration (caries) of the vertebra, or of several vertebrae, occurs, and if the case runs on unchecked extensive abscesses may form in the thigh, loin or groin. The trouble is often begun by a blow or by a sprain of the spine, which, by lowering the power of resistance of the delicate bone, prepares it for the bacillary invasion. The earliest symptoms are likely to be a dull aching in the back with stiffness of the spine. The child complains of being tired, and is anxious to lie down and be left quiet whilst his little companions are running about. If the disease is in the middle part of the spine, pains are complained of in the front of the chest or at the pit of the stomach. Unfortunately such pains are often ascribed to indigestion. If the disease is in the upper part of the spine the pains may be in the head, the shoulders or the arms. If in the loin-region of the spine they are in the lower part of the trunk, the thighs or the legs. (These obscure peripheral pains are often misunderstood and are apt to be attributed to rheumatism). The back is stiff so that the child cannot stoop. In trying to pick up anything from the floor he keeps his back straight and bends his knees. If the disease is in the neck-region he cannot easily look upwards, and, instead of turning his head to look sideways, he wheels round his whole body. In some cases, though the disease is far advanced, there have been no complaints of pain in the back. As the bodies of the vertebrae crumble away, the spine bends forwards under the influence of the weight of the head and of the upper part of the trunk, and a projection may appear in the middle, line of the back. In the neck, and in the loinregion, the projection is rarely well marked, but in the chest-region a conspicuous boss may make its appearance - the " hump-back." The projection is often spoken of as an angular curvature - a contradiction in terms, for a thing which is angular is not curved. When the deformity is great there may be pressure upon the spinal cord with more or less paralysis in the parts below.
The treatment of tuberculous disease of the spine demands absolute and uninterrupted rest. The best thing is to put the patient flat on his back for as many months as may be found necessary, but not in a close bedroom. If he is compelled to lie in a bedroom the windows should be open night and day. If the patient is a child, he should be laid flat in a box-splint, or upon a thin horsehair mattress, and should be carried out of doors every day - but always lying flat. When the pressure-symptoms, such as the pains in the legs, thighs or arms, the " belly-ache," or the pains in the chest or neck have passed away, a firm leather splint may be moulded on to keep the parts quiet until consolidation has taken place, or a cuirass of poroplastic felt or of plaster of Paris may be applied. The danger in these cases is of leaving off treatment too soon: they must not be hurried, or the trouble will be likely to come back again with, perhaps, increased deformity. If the disease is in the upper part of the dorsal spine, or in the neck-region, a cervical collar of leather, or a double Thomas's hip-splint may be found useful.
In cases of advanced tuberculous disease of the spine, in which the spinal cord is compressed within its bony canal either by the posterior parts of the vertebral bodies or by inflammatory products, or in which, after severe injury, the cord is pressed upon by a displaced piece of bone, the surgeon may think it expedient to open the spinal canal from behind, removing in the procedure the posterior arches (laminae) of the vertebrae. The operation is called by the hybrid word laminectomy. Sometimes in the case of tuberculous disease, where the propriety of resorting to the operation is being discussed, the symptoms of the compression begin to clear off and the child makes a complete recovery without being operated on; the moral is that we should wait patiently and give Nature a full chance of doing her work in her own way. The operative treatment of these cases is not highly'satisfactory. Still, there are a certain small number of cases in which it may be given a trial.
The treatment of spinal abscess has been greatly influenced by the Listerian method. The collection of broken-down tuberculous material or fluid is not an abscess in the usual sense, for it does not contain " pus " or " matter," being, as a rule, destitute of septic micro-organisms. A spinal abscess is therefore no longer drained: it is incised, scraped, washed out, and swabbed dry, the opening being carefully and permanently sewn up. In this way septic germs are effectually excluded from the cavity, and the patient is spared the depressing and tedious discharging of the cavity which so often followed the old methods of treatment. It must be clearly understood, however, that every spinal abscess does not undergo cure after being subjected to the evacuation and closure treatment mentioned