LUXATION. 



to put tlie fore-arm and hand in fplints, as in the cafe of a 

 fradiire. (See Fracture.) I'he arm mull alfo be kept 

 pt-rfiAly at reft in a fiing. 



When the ruptured ligaments have ur.itcd, the ufc of lini- 

 ments will tend to remove the remaining ftiffnefs and wcak.- 

 nefs of the joint . 



Liixa'ions of the Bones of the Carpus and Metacarpus. — A 

 didocat'on of the carpal bones from ca.h other feerns almofl 

 impofiible. The 03 magnum, however, has been known to 

 be luxated from the deep cavity formed for it by the fca- 

 phoides and femilvinare, in confequence of too great a 

 floxion of the bones of the fird phalanx on thofe of the 

 fecond, and it forms a tumour on the back of the hand.. 

 Chopart. Boyer. Richerand. 



The metacarpal bones are never luxated from each other. 

 The firll one is fometimes, though very rarely, pudied off 

 the trapezium. 



Luxatious cf the Fiiig;rs. — Th? fir.1 phalanges may be 

 diflocated backwards off the heads of the metacarpal bones. 

 A luxation forwards would be very diiKcult, if not im- 

 poflible, becaufe the articular furfaces of the metacarpal 

 bones extend a good way forwards, and the palm of the 

 hand makes refiitance to fuch an accident. The firft pha- 

 langes of the thumb and lirtle finger can alone be diflocated 

 inwards; and tlie firft phalanx of the thnmb is ahme fub- 

 jeil; to be luxated outwards. This phalanx is alfo moft 

 liable to diflocations backwards, behind the head of the 

 firft metacarpal bone, in which cafe it remains extended, 

 while the fecond is bent. 



Thefe diflocations flio'jld be fpeedily reduced ; for, after 

 eight or ten days, they become irreducible. In a Inxation 

 of the firft bone of the thnmb, which was too old to be 

 reduced, Default propafed cutting down to the head cf ihe 

 bone, and pufliing it into its place v.'ith a fpatula. Diflo- 

 cat/Ons of the thumb and little finger inwards, that of the 

 thumb outwards, and luxations of the firil phalanges of the 

 other fingers backwards, are all reduced by making exten- 

 fion on the lower end of the affected thumb, or finger. 

 The firft and fecond phalanges may alfo be diflocated back- 

 wards. 



After the reduction, the thnmb or finger afTcfted fhonld 

 be rolled with tape, and incafed, and fupporred in palle- 

 board, til! the lacerated licranients have united ; taking cai'e 

 to keep the hand and fore-arm quietly in a fling. 



LiUxations of the Femur, or Thigh-hone, at the Hip — Thefe 

 <liilocations may take place upwards and" outwards on the 

 excrnal fiirface of the os ilium ; upwards and forwards on 

 the body of the os pnbi; ; downwards and inv.'ards on the 

 foramen ovale; and downwards and outwards on the os 

 iUliium. 



The luxation upwards and outwards, and that downwards 

 and inwards, are the moft frequent, and it ir, not eafy to fay 

 which of thefe two cafes happens molt often. It is to be 

 iriderliood, however, that diflocations of the hip are far 

 lefs common than thofe of the (hnulder. We have feen 

 onlv three cafes of the firfl defcription ; but, at leaft, from 

 fifteen to twenty diflocations of the fhouldcr. Mr. Hey in- 

 forms us. that feven inftances of the latter accident, and three 

 of the former, are all that liavo occurred in his praftice. 

 (Praft. Obf p. JT4. edit. 2.) The following account of 

 luxations of the thigh-bone at the hip is from Boyer's work 

 on the Difeafes of the Bones, tranfl. by Farrell. 



No anatomical reafon can be given for the frequency of 

 the diflocation upwards and outv/ards ; the o Jge of the ace- 

 tabulum projects more at the fuperior and exterior parts than 

 at any other ; the orbicular ligament, v.hich is very thick 

 at this place, and the interior ligament of the articulation, 



which muft be previoufly ruptured, oppofe the diflocation 

 in this diredlion. There is little, on the contrary, to oppofe 

 the luxation dov.'nwards on the foramen ovale. The inferior 

 and internal part of the circumference of the cavity, the 

 place by which the bone cfcapes in this fpcc'es of luxation, 

 prefents a deep notch formed into a hole by a ligan cnt, 

 under which the vcfftls of the articulation enter. The or- 

 bicular ligament is thinner here than at any other olace ; 

 the motion of abduttion, in which thiii Inxation t;:kes place, 

 is more cxtenfive than that of adduction ; and laflly, thi 

 round ligament within the articu'ation does not oppofe it, as 

 it may take place without its being ruptured. 



Luxation upwards and forwards is very rare ; that down- 

 wards and backwards is flill more fo ; and, perhaps, as 

 fliall be cbferved farther on, never occurs but fecondarily. 



When, by a fall from a place more or lefs elevated, on 

 the foles of the feet, or on the knee?, the thigh is puflied 

 forwards and inwards, the head of the femur, forced to- 

 wards the fuperior and external part of the acetabulum, 

 breaks the internal and orbicular ligaments, efcape^ through 

 the laceration in the latter, and afcends on the external face 

 of the OS ilium ; but as the part of the os ilium immediately 

 above and at the external fide of the cavity is very con- 

 vex, t!;e head of the femur foon abandons its firll pofition, . 

 and Aides backwards and upwards wXo the cxterr.al fofia 

 of the OS ilium, following the inclination of the plane to- 

 wards this foiTa, and obeyino' the :-.6tion of the gint'<£i rauf- 

 clcs, wliich draws it in this diredtion. The head of the fe- 

 mur, in afcending thus on ihe external face cf the os ilium, 

 pufnes upwards the gluteus minimus, which forms a fort of 

 cap for it ; and the gluta;us maximtis and m.edius are rclaxedby 

 the approximation of the points into which they are inferted. 

 The pyriformis is nearly in its natural I'ate, the gemini, ob- 

 turatores, and qifadratus fcmoris, are a little elongated. 

 The pfoas magnus and iliacus internus are relaxed, as are 

 alfo the other mufcles inferted into the trochanter minor. 

 If to this defcription it be added, that the orbicular liga- 

 ment, torn at its fuoerior part, is ftretched over the aceta- 

 bulum, and covers it, an exail idea may be formed of the 

 change occafioned in tiie furrounding parts by this luxation 

 of the femur. 



The affefted thigh is fhorter than the found one ; it is a 

 little bent, and carried inwards. The k.ee inclines more 

 forwards and inwards than the oppofite one ; the leg and 

 tliigh are turned inwards, and the foot points in this direction. 

 The trochanter major is brought nearer the anterior and fu- - 

 pcrior fpinous procefs of the os ihum, and is at the fame 

 time elevated and carried a little forwards ; the latter cir- 

 cumllance m.ay be confidered as the neccfTary confequence 

 of the rotation inwards of the thigh. The natural length 

 of the limb cannot be rellored without reducing the lux- 

 ation ; the foot cannot be turned outwards, and any attempt 

 to do fo caufes pain ; but the inclination of the foot in- - 

 wards may be increafed. If the patient endeavours to 

 walk, he extends the foot to put tiie top of it on the 

 ground ; and though the heel is raifcd, he is flill lame ; for 

 thedifeafed limb remains always lliortcr than the other, and . 

 the pain occafioned by the attempt to walk renders progref- 

 fion flill more difficult. 



Luxation of the femur upwards and outwards has nothing 

 in common with the frafture of the neck of this bone but 

 the fliortnefs of the limb. The eafy rotation of the member 

 outwards and inwards, &c. &c. preclude a 1 pojlibility of 

 confounding them, unlets 'ihe furgcon be remarkably inat- 

 tentive. 



It in difficult to affign the caufe of the foot and remainder 

 of the limb being tuvQcd Liwards in this luxation. It may 



be 



