KNEE-JOINT, ABNORMAL CONDITIONS or.—The abnormal conditions of the knee joint may be arranged under those which result from disease and accident. The deviations oc casionally met with as the consequence of con genital malformation are fortunately rare.
Dtsnasr.—The abnormal appearances in the knee-joint resulting from disease are those which spring from some specific irritation, such as strums, gout, rheumatism, syphilis, or malig nant disease, or from direct violence. Most of these irritations affect all the structures of the articulation, and are associated with some form of inflammatory action, either acute or chronic.
Simple acute inflammation of the knee-joint, or acute arthritis genu, may be the result of a contusion, a sprain, or a wound; or there may be no assignable cause. In the latter case it may have been preceded by rheumatic fever, erysipelas, or diffuse inflammation, which had previously engaged distant organs and other structures. The symptoms are usually strongly marked. Considerable pain, which conies on very suddenly, is felt in the knee ; the leg in most cases soon becomes flexed and reposes on its outside ; and the patient cannot bear the slightest movement to be communicated to the knee-joint. There is considerable increase of temperature in the skin over the affected arti culation, together with tension of it from in ordinate effusion of synovial fluid into the joint. Although the usual phenomena of red ness as an accompaniment of phlogosis may not be observed externally, there can be but little doubt that the capillary vessels pervading the different structures of the interior of the joint are in a state of The patient'has but little sleep, and this is frequently inter rupted by unpleasant dreams and painful spas modic startings of the affected extremity. lede ma of the lower part of the limb now occurs, and in severe cases sometimes extends up the whole leg and thigh, even to the groin. The sympathetic fever may run so high, and the swelling and other local symptoms proceed so rapidly as to deprive the surgeon of any oppor tunity of proposing or performing amputation to save the patient's life.
The fever in well-marked cases of acute ar thritis genu is sometimes symptomatic of the local disease ; sometimes it has preceded the local affection, and has been ushered in by a very severe rigour followed by profuse perspi ration. Like the disease, the fever will vary in
its character. Erysipelas, rheumatic fever, and diffuse inflammation, as has been mentioned, will each occasionally present in their progress examples of the disease of the knee-joint now under consideration, and the accompanying fever will bear the character of the disease with which the inflammatory affection of the joint is associated. The local phenomena presented by an acute arthritis genu do not, however, vary so much, except in degree and severity.
Acute arthritis genu may supervene as a consequence of wounds. Sometimes these wounds are very small. We have known one case in which a puncture made with a fine sew ing needle, which was accidentally driven with force into the knee-joint, at the inside of the patella, was the cause of a fatal inflammation of the joint : the point of the needle probably penetrated the bone. The patient, a young woman, was under the care of Mr. Colles many years ago, in Steevens's Hospital. In some instances we have known inflammation of the synovial membrane of the knee to have been the result of a wound of the subcruneal bursa. A countryman had received a trans verse wound by the cut of a broadsword just above the patella, and fatal inflammation extended from this bursa, which was opened, to the synovial sac of the knee-joint.
Acute inflammation of the knee-joint has been the result of surgical operations, such, for instance, as that occasionally undertaken for the extraction of moveable bodies which form in the joint and interfere with the due perform ance of its functions. This operation, we be lieve, is now very seldom recommended. We have heard and read of many cases in which it has been performed with complete success; on the other hand, we have reason to know that many have died of the inflammation con sequent on it, and that others have narrowly escaped with their lives, having ever after wards an anchylosed knee-joint. It is rather singular, but we believe it to be true, that the inflammation resulting from a valvular opening having been made in the knee-joint has not come on for six or seven days after the moveable cartilage has been extracted; but in flammation being once set up, its course is ge nerally acute and dangerous.