Although paralytic deformities consist of joint contractures and • arise in consequence of various forms of paralysis, and therefore form part of the joint contractures already under discussion, yet they form a special group in regard to treatment by medical gymnastics and demand special consideration here. This is the more necessary since the treatment of these deformities has recently changed so much by the introduction of new methods, and medical gymnastics is therefore only one of the various means of treatment.

These deformities originate after various diseases which affect the central motor apparatus of the brain or spinal cord, generally after an acute poliomyelitis, when the remaining paralysis in severe cases has reasonably been regarded as hopeless, and our treatment powerless. It is not only on account of the loss of functional power which of necessity follows every paralysis, but also because of the severe deformities which accompany this disease, that it has such a bad reputation. By observing the manner in which these deformities arise we shall be able to find a method for effective treatment by medical gymnastics and massage for the different stages of the disease.

The muscles around a normal joint are grouped in such a way that they partly hold the joint in a certain resting position, partly permit a certain number of varied movements from that resting position by which the joint carries out the different functions of the limb. If one or several of these muscles become paralysed, the equilibrium is upset and the normal resting position is thereby changed. Since a partial limb paralysis often remains as the result of an acute poliomyelitis or similar disease, a similar change must take place in one or more joints. Thus arises the paralytic joint deformity, which is a joint contracture due entirely to muscle change. The treatment in such cases must be of quite another kind from that already spoken of in cases of contracture caused by joint disease. As long as there is a lack of equilibrium between the muscles around the joint a paralytic deformity is inevitable. By forced correction in such cases one can only bring about a temporary improvement if nothing can be done to replace the equilibrium of the muscles, or by some other outside means at least to counteract the recurrence of the deformity.

Medical gymnastics and massage have long played an important part in the attempt to restore the muscular equilibrium. The aim of the treatment by medical gymnastics varies a great deal during the different stages of infantile paralysis.

In the first stage of acute poliomyelitis, when the paralysis is often more widely extended than in the last fixed stages, it has been observed that thorough and regular massage and corrective exercises help in the restoration of the power of movement of the paralysed muscles. In paralysis due to poliomyelitis the reason why the paralysis is so much more widely extended directly after the illness than later on is due to the fact that not all the motor cells and paths which have been affected by the toxins of the disease have been destroyed, but that a greater or lesser number of the damaged cells are capable of recovery. To what extent medical gymnastics and massage can help in this stage of repair in poliomyelitis is uncertain; but probably treatment does not play such a great part as has been ascribed to it by gymnasts. By this we do not say that such treatment has no effect in this stage. At any rate, the treatment helps in a great degree to prevent secondary deformity, which must certainly be treated by remedial joint movements given daily. When the case of poliomyelitis has got past the stage of repair and the definite paralysis has become completely stationary, and the gymnast as well as the patient and his friends can see no further improvement, the treatment is left off by degrees, and the medical gymnast probably meets the patient again at a later stage in his life.

When the first medical gymnastic and massage treatment is discontinued the patient is often forced by necessity to manage with his functional defect as best he can, and thus the paralytic deformity gradually develops with mathematical certainty, the degree or nature of the deformity depending upon which muscles and how many have been permanently paralysed by this terrible disease.

In more fortunate cases orthopaedic apparatus may often prevent the occurrence of any deformity and secure for the patient fairly good functional power, depending naturally on the degree of the muscular defect. But in many cases no benefit can be gained by such external apparatus. Muscles which are not acting in harmony with one another seem to possess an almost incredible power of producing deformity. It has often been observed how in paralysis of Extensor Communis Digitorum and the Peronei the corresponding typical deformity, pes equino-varus paralyticus, arises, in spite of a carefully-constructed surgical boot, and in spite of the fact that the patient was at first able to walk on the sole of the foot, so that the body weight at each step tended to prevent the development of the deformity.*

It is difficult from the economical point of view for even wealthy patients to give sufficient attention to orthopaedic apparatus, for it is no easy matter to get the apparatus to fit and to keep it in good repair. After vain attempts to prevent the deformity many patients are at last forced to abandon the whole question of apparatus and the use of orthopaedic supports, and the deformity, although originally it could possibly have been counteracted, must at last arise. One may say that only a very few of the wealthier class are fortunate enough to prevent the deformity by the use of apparatus. It arises gradually, and by its increasing functional effect often results in marked crippling. The patient then frequently seeks new help and advice, either from the physician or direct from the medical gymnast, who now meets a poliomyelitis in a quite different stage of the disease. Not even the most sanguine gymnast can give any hope of restoring the functions of muscles which have been paralysed for years. On the other hand, he may try by the help of manual correction and massage to soften the tissues and improve the circulation and thereby give the deformed limb a more normal appearance. This can be done successfully, without doubt, by hard work, and many gymnasts (de Ron, for example) have achieved successful results by very energetic treatment of these deformities; but the deformity must of necessity recur when the treatment is stopped. The disease has therefore come to be considered hopeless. Recently orthopaedists have attempted in their treatment to attack the causation of the disease with undoubted advance in this hitherto thankless branch of orthopaedics.