(From Anchylosis 632 crooked). A stiff joint, a species of which is called orthocolon. It is a species of contractura in Cullen's Nosology. When the bones are immoveable, and the joint in a bent position, it is called ancyle: but if the limb be straight, and cannot be bent, orthocolon. Petit divides this case into the true and false; in the true the bones are united; in the false, from the contraction of the tendons, the limb is rendered immovable, without the joint being injured.

The bones are covered at their ends, where they form joints, with cartilages, to facilitate their motion, and to prevent any further production of bone; and if these cartilages should be eroded, a bony excrescence will follow, and produce this disorder: it is sometimes, however, the cure of worse misfortunes.

The general causes are, a caries, abscesses in the joints, ossification of the ligaments, scrofula, and rickets, contraction of the tendons.

When the bones are united, the cure is impossible . and, whatever else may be the cause, very uncertain, on account of the difficulty of reaching the seat of the disease; often from the difficulty of knowing the part of the joint principally affected.

The most simple case of this kind is that from a long confinement of the limb to one position; an inflammatory affection of the ligaments, from external injuries, is generally difficult; rheumatic and arthritic matter falling on the joint hardly ever to be removed; but the worst case is that from a white swelling, a scrofulous disease.

If the cause is a rigidity of the tendons, emollient topics are the proper means of relief. Dr. Lobb, from observing the glovers soften hard leather with a mixture of the white of egg and water, proposed it in some instances of this kind, it is said, with the best success.

Others commend mucilaginous oils, of which the neat's foot oil is the best.

If an inflammatory state of the ligaments is the cause, astringent and stimulant applications, and not emollients, are the best. Blisters, the most powerful remedy of this sort, have in many instances succeeded in this--case while it was in a recent state; but many blisters must be often applied in succession.

In more inveterate cases a few cures have been effected by the pump. Warm or cold water, falling from a considerable height upon the part, hath, by repetition, been successful. The warm bath hath had the like happy effects by continuing in it an hour or more, and repeating the application for several weeks successively. After the bath or the pumping, emollients may be applied.

When the joints themselves are not diseased, pumping and friction are perhaps the best remedies, gradually exercising the joint by a motion, which extends the muscles without giving great pain. When some mobility is obtained, the extension of the muscles may be preserved by any instrument, which keeps them in the state procured by the action of the remedies. Mr. Bell has recommended an useful machine for preserving this extension in the knee joint; and MM. Koeler and Trampel have described others, in no respect of superior efficacy.

Of the applications, some have preferred the more stimulating and astringent, as the fat of ducks, the brine of herrings with vinegar, vitriol, or alum; arum root often joined with the cicuta; the sabine ointment applied to blistered parts; oil of marjoram, turpentine, etc. Others recommend the more relaxing oils, the althaea ointment, with warm applications of water and vapour. The gum ammoniac with vinegar of squills is supposed to have a good effect, on a principle not easily explained. In general, where there is a deficiency of the synovia of the joint, the stimulating applications are the best; where the fault is in the rigidity of the tendons, the, relaxing ones.

In scrofulous cases, all means hitherto use3 have failed; however, as palliatives, when the tumour bursts into ulcers, the aqua lithargyri composita, and similar preparations, are considerably beneficial.

See Petit on the Diseases of the Bones. Heister's Surgery. Mem. de lacad. Royale des Sciences, years 1721 and 1728. Aikin's Obs. on the Preparations of

Lead. Bell's Surgery, vi. 283. White's Surgery, 431. Boyer on the Bones.