JOI 



concealed entirely within the partition, or folded cloCe to it ; 

 they are ufed for the pilrpofe of making a free commnnica- 

 tion between one foom and another, at great meetings or 

 balls, when any one of the rooms would be infufficient 

 though large enough for common ufe. 



/"/> 9. tlic elevation of a door to be folded clofe to the 

 partition, by means of a hanging ftyle, or pilader. on each 

 Jide which 1? firft hung to tiie jamb, then a folding door to 

 each pilafter. 



Fig. 10. is a door confiding of four parts : each middle 

 part is hinged to each extreme part ; each two parts, on 

 each fide, in time of company, may be removed entirely 

 out of the way into hollows on each iide of the partition, 

 and guided by grooves at the top and bottom, and made to 

 Hide freely upon rollers. 



F;». II. is a jib-door, that is, fuch a door as, when (lint, 

 may be as much concealed as pofllble from having the ap- 

 pearance of a door. Jib-doors are ufed, when only one 

 aperture at the end of the fide of a room is necelFary ; and 

 when it is required to keep the fymmetry of that fide, witliout 

 having the appearance of a door ; the bale, fuibafe, and 

 paper are, therefore, continued o'er it ae in the other parts 

 of the room, the joint being only feen at the top, and upon 

 the edge oppofitc the hinge. 



JOINING of Is&iE. See Issue. 



JOINT, the juncture, articiJation, or affemblage, of 

 two or more things. See Articul.\tiox. 



JoiVT, in Anatomy, the connection of two or more hones 

 to each other : thefe parts are generally fo organized as to 

 admit of motion, but in fonie intlances tliis is not the cafe. 



The joints or articulations are generally referred to three 

 clalfes : the immoveable, or J'ynarlhrojis ; the half moveable, 

 or amphiarihrcji; ; and the completely moveable, or tllar- 

 tbrsfi. 



The firft of thefe includes the various kinds of future ; 

 for the defcription of which, fee Cr.wilm. 



The amphiarthrofis, or joint admi;ting of flight motion, is 

 made up either of cartilaginous Hgaments {fynipL'yJii), or 

 of true cartilage {fynchomlrofs). The union of the bodies 

 of the vertebrae to eacti oth^-T) and the articulations of the 

 pelvis, are examples of the former : tile connection of the 

 firll pair of ribs to the fternuni, and of the different bones 

 of the ilernum to each other, cxempHfy the latter. 



For the account of the third fpecies, or moveable articu- 

 lation, fee Di.'VRTuno.sis. 



A general defcription of the compofition of a joint will 

 be found under the article Exthe.mities, near tlie begin- 

 ning ; and in the fame article the particular joints of the 

 limbs are defcribed. The account of tlie articulation of the 

 lower jaw is given under Deglvtition" ; that of the con- 

 nection of the head to the vertebral column under Hi;.-iD. 

 The articulations of the vertebrs are confidered in the 

 article Spine ; thofeof the ribs, in Ribs ; and of the pelvis, 

 in Pelvls. 



.To.'NTS, Difeafes of. Under this head we intend to notice 

 a few cafes which belong to the department of Surgery, and 

 are not elfewhere treated of in this publication. 



Inflammat'wn of Joinls. — Idiopathic cafes of this kind are 

 not common. The complaint ordinarily originates in con- 

 fequence of a contufion, fpr.iin, wound, or other kind of in- 

 jury d-me to the part affefted. Phlegmonous inflammation, 

 wlierefoever lituated, is uniformly attended with certain local 

 fymptoms, by whicli both its prefence and degree may be 

 afccrtaincd. Pl-eternaturdl rednefs, Incrcafed heat, a throb- 

 bing pain, and a tenfe fwelling, affcv'-^ing the feat of its 

 attack, are the common marks which denote its exillence 

 in all fituatiuns. WHicn a joint is inflamed, thtx fame Ijcal 



jOf 



phenomena ai'e pivfent, and the conditutio!) is dillurbed by 

 the ufual fymptoms of inflammatory fever ; but in thefe 

 Cafes they are apt to be exceedingly fevere. The inflam- 

 mation attacks the capfular ligaments, and not remaining 

 confined to any particular portion of them, it very quickly 

 diffufes itlelf univerfally over their whole extent, as is com- 

 monly the cafe in all inflammations of fmooth membranes. 

 That there is this peculiarity in inflammation of membranes, 

 is often ihlkingly proved in the inllance of peritonitis, 

 arihng after the operation of lithotomy. Here, we know, 

 that the inflammation commences in the bladder, is communi- 

 cated to the portion of the peritoneum which covers the fun- 

 dus and pollerior furface of this vifcus, and thence rapidly 

 fpivads over the v.'hule extent of the abdomen. 



The capfules of the joints are naturally endued with little 

 fenfibllity ; but, like the gums, and feveral other parts in a 

 fimllar iiate, tliev l>ecome acutely painful when inflamed. 

 The complaint is accompanied by an increafed fccretion of 

 the fynovia, which becomes of a more aqueous, and of a lefs 

 albuminous quality than it is In a healthy (late. Hence 

 this fluid is not fo well calculated for lubricating the arti- 

 cular furfaces and preventing the effects of friclion, as it is 

 in the natural condition of the joint. This circumilance 

 may explain why a grating fenfation is often perceived on 

 moving the patella when the knee is inflamed. 



The capfules of the joints may, as well as other mem- 

 branes, be thickened by inflammation. At other times an 

 exudation of coagulating lymph may take place upon their 

 internal furfaces ; and as, by a general law of the animal 

 economy, the contiguous veffels are always prone to Ihoot 

 into lymph thus L-ff"ufed upon an inflamed furface, the con- 

 fequence frequently is, that organized fubllancr,--, fuch as 

 pieces of cartilage and bone, are produced in the interior of 

 the joint. The inconveniences of thefe extraneous bodies, 

 and the mode of relief, will be a fubjeft v.hicli we Ihall pre- 

 fently have to confider. 



Wlien the Inflammation is more vehement, fuppnration 

 may liappen within the capfidar ligament. Unfortimately, 

 this is by no means an unfrequcnt occurrence. At lengtli 

 the capfular ligament ulcerates, and purulent matter is ef- 

 fufed beneath tlie integuments. Tlie flcin may next ulce- 

 rate, fo that the abfcefs is difcharged, and the cafe fecms to 

 be fomewhat benefited. The openings through which fuch 

 collections of matter are difcharged, will be found, upon 

 examination with a probe, to be the terminations of finufes 

 leading into the cavity of the joint. 



A large joint feldom fidls into a flatc of fuppnration, in 

 confequence of acute inflammation, Without th.e conllitution 

 being at the fame time fo dllhirhid. that life itfelf is greatly 

 endangered. In the moll violent ilate of the inflammation, 

 or that which is the immediate forerunner of fuppuration, 

 the pulfe Is CAceedlngly frequent ; but not quite fo full and 

 (Irong as it would be if the part aflfefted were of a ilruduro 

 better adapted to refill the ravages of dlfeafe. The patient's 

 flcln is dry and hot ; he is refllefs and vigilant ; and, in very 

 bad cafes, delirium and coma may cnfue, and end fatally. 



But the rapidity with which the common inflammatory 

 fever afl'umes in fuch cafes the hettic type is a circumilance 

 which muil not be pafled over in fdenc'e. When an abfcefs 

 has formed in a large joint, in confequence of a fevere at- 

 tack of common inflammation, the patient immediately be- 

 gins to be affccled with hectic fymptoms, and tlse flror.g 

 aClion attendant on the inflammatory fever fuddenly ceafes. 



Local confcquences, even worfe than ihofc above defcribed, 

 may follow inflammation of a joint. As the layer of the 

 capfular ligament reflefted over the cartilages of the arti- 

 culation is often inflamed, the cartilages themfelveJ are very 



hablc 



