JOINTS, SURGICAL DISEASES OF.
Varieties, — The affections to which joints are liable are almost all clue to inflammation and its results. Their character varies according to the causes which originate them and the extent to which the disease progresses. If the in flammatory action is confined to the lin ing membrane of the joints, then it is designated as a synovitis. If, however, it goes farther, and involves the remaining structures in addition, then it is spoken of as an arthritis. If pus is a prominent symptom, it may be called a purulent synovitis or arthritis, although when this occurs it is more apt to be regarded as an arthritis. Micro-organisms play an im portant part at times in joint-inflamma tions. These are usually of the ordinary pus-producing kinds, such as produce suppuration in ordinary wounds, or sep sis. When this is the case, one speaks of a septic arthritis. If the exact source of the infection is known, then the specific cause of the affection results in naming it according to its origin. Thus one speaks of rheumatic, gouty or tubercular arthritis, also of gonorrluval or syphilitic. Sometimes a special name is given, such as osteoarthritis, not indicating its ori gin, but rather the parts affected; also Charcot's disease of the joints, so named after him who described it.
Loose bodies in joints occur as the re sult of injury or disease. When the dis ease affecting a joint pursues an extreme course, the functions of the joint are de stroyed and it may no longer bend. This state of more or less complete fixa tion is called ankylosis, and, after the diseased process has died out and en tirely ceased to act, it alone remains and may be the cause of the patient's seek ing the surgeon and dema.nding relief.
Synovitis.
Synovitis is the name given to a sim ple inflammation, which is supposed to he limited to the synovial membrane. It is apt to be incorrectly applied, at times, on account of other structures of the joint being affected at the same time. The term simple synovitis is of consider able service to designate those inflarrmaa tions which cannot be traced to specific irritants, such as gout and rheumatism, nor to disease of contiguous structures, such as the bones.
symptoms are those common to inflammations in general, such as pain, heat, redness, and swelling, with impairment of function, as well as others due to the peculiarities of the special structure or part involved.
ACUTE SYNOVITIS.—In acute synovitis
the pain may vary from slight to ex cessively severe. The rapidity with which the effusion may occur can cause intense pain by distension of the joint capsule. The joint may be red and hot to the touch and very tender. The swelling is due mainly to distension of the joint, both by the increase in size of s‘no‘i.11 fr.tig.. and to the increased SINL1ling is a most important s%1‘.1 tL and it is much more marked asLs than in others. In such as the knee, that are not deeply Low.L.1 bv soft parts the swelling is arl.LLI 11111.1 peculiar in shape, while in t host. liicl" are not so superficial, as the slhouldL r and hip. it may be so slight as int to be Lvident. In these latter joints there inav be a slight uniform enlarge 'mut which it would be difficult to say was not dim to the bruising of the soft lams in case the affection followed an :njurv. ln the knee and ankle, on the ntrary, the swelling may be 'narked, and follow accurately the outlines of the ints. It is influenced in its shape by thy L Ntrlying structures. Thus, in the knee-joint the swelling of the synovial fringes below the patella causes a pro trusion at that point, which is more marked on each side of the tendo-patelbe. There may be a swelling above the pa tella or on each side. The patella. is like wise lifted up away from the femur by the effusion, forming the so-called float ing-. patella; or, pushing the patella down ward, it can be felt to strike against the condyles beneath. When the sublemoral bursa communicates with the joint, the swelling often extends quite a distance above the patella. In the ankle-joint the swelling is more toward the sides, but is also seen in front. Behind, it is not sn marked except on each side of the tendo Achillis, which, however, does not play so prominent a part in the symp toms of affections of this joint as do the patella and its tendon in those of the knee. In the elbow the tendon of the triceps muscle also causes the swelling. to be more marked on each side than in the middle. Impairment of function is usu ally marked, and movements are very pa;r: ful in the acute type of the affection.
Not only does pain interfere with the joint's functions, but the effusion into and distension of the joint prevents it from performing them by rendering it looser and less secure; so that weakness is marked. and, even if pain is absent, the joint is practically useless.