HIP, ABNORMAL. CONDITION OF.) Both knee-joints in this case are affected with this disease, but the left is more distended by fluid than the right. The inner condyles of the femur and tibia of this limb are thrown somewhat inwards, and form a salient angle in this direction, which, the patient says, is cer tainly the result of disease, as his limbs were perfectly straight before he was visited by his present illness.
Although his knee-joints are more affected with this chronic disease, his other joints pre sent very evident traces of this afflicting malady. The disease in him followed a rheumatic fever, which was brought on in consequence of his having lain a whole night asleep on a wet road, having fallen unobserved from his cart when in a state of intoxication.
Although this is not the place to speak of treatment, we may be permitted to say that under the influence of rest in bed and a mild mercurial course, followed by a long-continued use of sarsaparilla with large doses of the hydriodate of potass, this man left the hospital, by no means cured, but much improved and tolerably well able to follow his occupation.
Ile found it necessary, however, after the lapse of three years, to seek re-admission into the hospital, where he now is. The right knee joint is now enlarged, and in a condition simi lar to that of the left on his first admission. The latter, on the contrary, has nearly resumed its normal condition ; the dropsical effusion of synovia has disappeared ; he does not com plain of pain in it; but if the joint be accu rately examined, the bony irregularities which were noticed on the head of the tibia will be found, as might be expected, still to exist. If we move the patella transversely, an articular crepitus is perceived, plainly sheaving that the cartilages have been removed from the patella and corresponding trochlea of the femur. The edges of the trochlea can also be felt through the skin to be elevated into rising crests. The peculiar crackling noise which is elicited when the joint is flexed and extended is infinitely more remarkable in the left knee-joint now, when it is comparatively well, than formerly, when it was much swollen, and when the syno vial membrane was in what has been called a dropsical condition.
Anatomical characters.—When we have an opportunity of making an anatomical examina tion of a knee in which the disease had been fully established, we find the synovial fluid increased in quantity, and but little altered in its sensible qualities. The membrane is thicker than natural, and opaque. Sometimes vascular synovial fimbriie are formed, and hang into the synovial sac.* We also find moveable carti laginous bodies in the interior, similar to those noticed in the elbow-joint.t (See ELBOW, ABNORMAL CONDITIONS or.) In the line of flexion and extension we observe narrow sulci formed by the removal of the cartilages. On examining the popliteal tumour, we find it to be, what we might have surmised, an enlargement and dropsical condi tion of the bursa, which naturally exists at the point of decussation of the semi-membranosus tendon with the tendon of the internal head of the gastrocnemius. This bursa communicates normally with the synovial sac of the knee joint by a very small circular aperture. It is not an uniform ovoid sac, but evidently has semilunar septa irregularly thrown across its interior, making the bursa a small multilocular cavity. When the joint is much distended by synovial fluid, the bursa admits some of this fluid, and takes upon itself the same morbid process which affects the proper synovial mem brane of the joint itself. As we examine the disease when it has existed for some time, we find that the cartilage has been removed in grooves, and its place supplied by a porcelain ous or ivory deposit. The bones of the knee joint, however, present appearances charac teristic enough : they generally appear to be enlarged. This is obviously the case with the patella: it is broader than natural, excavated, and grooved vertically. All the bones seem enlarged and porous on all those parts of the articular surfaces which have not been worn by use into porcelainous polished surfaces and Rile'.