4. The Condition Of The Muscles Acting On The Joint

The muscles in a case of stiff joint are naturally wasted more or less. The wasting may be slight or extreme, and in the latter case the muscles on the proximal side of the joint may be reduced to a condition which is little better than that of fibrous cords. The wasting, whether slight or excessive, affects the proximal muscles mainly, i.e. the muscles which act directly on the joint under ordinary circumstances.

Speaking generally, the less the amount of mobility in the joint the greater is the wasting of the muscles, for obvious reasons. The wasting, however, is not always the same in similar cases, although these may be in all other respects apparently the same. From the point of view of the radical treatment of stiff joints by forcible bending, muscle waste in itself is not of great importance, but rigidity of the muscles in addition to wasting is of considerable consequence. Muscular rigidity in these cases arises mainly from two causes: first, physiological shortening from the effects of disease or persistent complete disuse; and secondly, matting of the muscles or muscle to the underlying bones from inflammation or injury, as examples of which may be mentioned the adhesions resulting from cellulitis or periostitis, and the matting of the parts about a fracture. The more rigid the muscle the greater must be the care exercised in the forcible bending of these cases, and it is important to determine as far as possible to what extent, if any, the stiffness of the joint is due to the rigidity of the muscles. Speaking generally, it will be found that the greater the rigidity of the muscle's the less favourable are the cases for the radical treatment. Although muscular rigidity in itself is no actual bar to attempts at breaking down, these when rigidity is present should be made with great care, as not only may rupture of muscle occur, but, what is worse, a bone may give way (Plate XI). The explanation of the danger of the latter calamity lies in the fact that where a joint has been for a long period quite stiff and the muscles extremely wasted the bone is always to some extent wasted also, a very important fact in connection with the present discussion and one which I do not think is sufficiently recognised. In fact the condition of the muscles is a fair indication of the state of the bone in the matter of strength; wasted rigid muscles indicate a weak bone, and vice versa.

5. The Condition Of The Bones

Beyond what has been already indicated there is little to be added under this head. Any obvious indication of bone weakness, such for example as loss of tissue, may in some cases altogether negative the propriety of breaking down a stiff joint, and in all cases should lead to great care in manipulation. On the other hand, it is well not to assume, because a bone, as sometimes happens, is thicker than usual from some pathological change, e.g. osteitis, that it is stronger than usual. Although as a rule bones so affected are stronger over the actual area of the thickening, they are not always so immediately beyond, and I remember seeing a fracture of the femur in a middle-aged man which occurred during the breaking down of a knee-joint, the fracture having occurred at the extreme upper limit of considerable thickening of the lower end of the femur from old-standing osteitis. In this connection the tendency of a new growth to simulate simple bony thickening must not be lost sight of.

Plate XL

Diagrams of an ankylosed knee-joint before and after ill-advised forcible flexion.

Assuming that in all cases the milder measures of massage exercises and passive movements have been tried without effect or with only partial success, the main points relating to the desirability or the reverse of resorting to the radical method of the forcible bending of stiff joints may be summarised generally as follows: 1. The less the movements of the articulations are restricted the better is the prospect of the radical method.

2. Fibrous ankylosis resulting from tuberculous disease, unless very slight indeed, should not be forcibly broken down. If in such cases the joint be fixed in a position which is inconvenient or painful to the patient, rectification of the deformity should, in joints where such a course is possible (e.g. the hip), be effected by an osteotomy at some distance from the joint, and not by 'breaking down.'

3. A stiff joint which is hot to the touch whilst it contains no fluid is unfavourable for forcible bending, the condition being usually due to tubercle in a quiescent but dangerous stage. Forcible bending in such cases is commonly followed by the lighting up of the quiet tubercle which results in abscess or worse developments.

4. A stiff joint which is hot to the touch whilst it contains fluid is not unfavourable for breaking down unless the ankylosis is practically complete, heat with effusion being commonly due in chronic incomplete stiffness to the dragging upon adhesions, the rupture of which cures the symptoms. If the ankylosis is complete, or nearly so, and there is coincident effusion and heat, breaking down of the joint should be conducted with great care and caution, as in such cases there sometimes exists a small area of diseased bone in the joint or immediately outside it.

5. Effusion without appreciable heat may be ignored for ordinary purposes in deciding as to the propriety of the forcible bending of a joint.

6. The less the muscles acting on the joint are wasted, and the better their physiological condition, the more freely, coeteris paribus, may attempts at breaking down be approached.

7. Rigid or adherent muscles should be regarded as unfavourable factors in this treatment, but are not insuperable objections.

8. Wasted muscles which are not rigid may be disregarded except in very long-standing cases, in which extreme muscle-waste is invariably associated with weakening of the bones; such cases, therefore, should obviously be approached with caution.

9. The ideal condition of a stiff joint for the purposes of the radical treatment by breaking down may be said to be as follows: moderate stiffness, absence of heat and effusion, with flaccid muscles. Any joint which is not absolutely stiff, which is not hot to the touch, which contains no fluid, and in which the muscles acting upon it are not rigid or adherent, may be broken down with impunity.

10. The neurotic element in stiff joints must be borne in mind. Stiff joints which are without increased local heat and effusion may, if the muscles are not wasted, be regarded for practical purposes as neurotic in origin.