In September, 1919, I had the good fortune to visit, by invitation, the United States of America. Unfortunately, I was only able to spend slightly less than two months in the country. During this time it was my privilege to visit a large number of medical men (privately and at their clinics) throughout a triangle whose angles are situated at Rochester, Minnesota; Boston, Massachusetts; and Washington, D.C. I was able, therefore, to carry through a considerable amount of investigation on the subject of physical therapeutics; but time being limited, I chose particularly as objects of inquiry sacro-iliac and sacro-lumbar "strain" and "sub-deltoid bursitis." I had heard frequent reference made to these conditions by many of the American surgeons whom I had met during the War, and my selection of them as subjects for investigation was due to this and to the fact that I had barely even heard mention of them at home.

The number of medical men who take any interest in physical therapeutics in the United States is surprisingly small. Nothing could have exceeded the kindness and courtesy shown to me by those I visited, or the trouble taken by them in demonstrating cases, and the various methods by which they are treated. I cannot feel, therefore, that it is owing to lack of opportunity or observation that the conclusions I was able to draw were indefinite, and that I have failed to return with any very clear-cut ideas. Rather I must attribute these things to the fact that in America, as well as at home, medical science has still much to learn on these and kindred subjects. I feel, however, beyond doubt that I have been shown the glimmerings of many important truths; and although without further experience my ideas must necessarily be unformed and raw, and though present conclusions may be liable to revision, I feel so convinced of the extreme importance of these fields of investigation, that I am compelled to insert the present chapter, although perhaps the material on which it is based has nothing, strictly, to do with massage.

Amongst the surgeons I visited I found the widest difference of opinion, ranging from those who hardly regard the conditions of sacro-iliac "strain" and "sub-deltoid bursitis" as worthy of attention, to those who consider them as responsible for an almost limitless variety of aches and other ailments. Even amongst those who hold the latter view there is a wide divergence of opinion, not only in detail, but even in the essentials of treatment. To take one instance only. In three separate clinics the condition known as sacro-iliac "strain" is treated by three different kinds of belt, and in each case the belt prescribed is regarded as the one and only satisfactory cure for the complaint. In a fourth clinic the use of belts of any sort is anathema, and reliance is placed almost entirely on manipulation.

In all four of these schools the existence of such things as gout, muscular rheumatism and fibrositis, as pathological conditions producing definite symptoms, is readily disregarded; while, on the other hand, those who pay little attention to sacro-iliac "strains" look upon these conditions as solely responsible for the production of the symptoms elsewhere attributed to "strains." Rarely did I find a definite distinction drawn between referred pain and pain due to local infiltration. Almost invariably the possibility of one or other condition being present seemed to be ignored. Time did not allow me thoroughly to investigate the various schools of thought in these matters, and my remarks upon them are therefore given with all reserve.

It was with great interest also that I investigated, as far as time allowed me, the work of the osteopaths and the cheiro-practors. Co-related to the practice of the latter irregular practitioners, it is impossible to overlook the high value placed upon the manipulation of the back in Swedish manipulations, and particularly by percussion in its various forms.

In sum, then, my investigations left me confronted with this problem. There are three schools of thought. In the first, sacro-iliac "strain" is held to be of trivial importance; in the second and third it is held to be of great importance, though the remedy extolled differs. As a result of sifting the evidence placed before me I think that, beyond all question, those who tend to ignore the existence of sacro-iliac and lumbar "strain" are wrong. If either of these conditions exists, the only problem is: Are they to be treated by support or by manipulation? In the second school the wearing of a belt is prescribed as the remedial agent, and in the third the choice falls on manipulation. Is there any possible manner in which these two schools can be reconciled, or do they together or separately give any definite contribution to medical science? At present I incline to the opinion that both methods of treatment are efficacious in suitable cases, but equally I am convinced that both can be injudiciously applied.

The first point to consider is: What is meant by sacro-iliac or lumbo-sacral "strain"? The less educated among the osteopaths and, I believe, almost all cheiropractors labour under the delusion that the symptoms for which they apply treatment are due to gross displacement of the vertebrae, though it is rare to hear the displacement referred to as a dislocation, "subluxation" being the usual term applied.1 Many are too ignorant to be able to define exactly what joints are supposed to be displaced, failing to distinguish between the joints that separate the articular processes and the joints between the bodies of the vertebrae. In one school of osteopathy, and I believe in more than one, teaching is definite on this point. It acknowledges that minor displacements of the inter-vertebral joints are impossible, and attributes all the evils for which treatment is applied to "subluxation" of the joints between the articular processes. All, however, are agreed that minor displacements of the ilium on the sacrum, or vice versa, do actually take place. Explanation of the effects of subluxation varies, though nearly all agree that it causes "pressure on the nerves." On what nerves is not usually specified. Granted the pressure, the explanation of its effects varies with the educational training of the person delivering the explanation.