opposite directions upon the lower ends of the radius and ulna while the hand was more or less supinated. It does not clearly appear that the cause has ever acted by carrying the movement of supination beyond its normal limit, although it is not improbable that this was the case in one or two instances. No post-mortem examination has been reported, and the pathology of the injury can, therefore, only be inferred. Desault, however, met with a specimen of an old dislocation in the cadaver of a man sixty years old; the hand could not be extended, and rotation was very limited. The sigmoid cavity of the radius was filled with cellular tissue; the head of the ulna, situated in front of this cavity, rested on a sesamoid bone to which it was attached by a capsular ligament. Other injuries had contributed to the loss of motion. The hand was cedematous; the flexor tendons, pushed outward, adhered to one another and to the skin; the elbow could not be extended, and both shoulders were dislocated forward (Malgaigne, loc. cit., p. 688). FIG 97. In an entirely unique case reported by Valleteau' the dislocation was compound. The patient's forearm had been caught between the spokes of a moving wheel; the ulna projected twenty-eight lines through the skin, crossing the front of the radius, which appears not to have been broken. Symptoms. The forearm is partly pronated or in varying degrees of supination, the wrist flexed or extended, rotation difficult and painful. The lower end of the ulna is prominent in front, with a corresponding depression behind, and sometimes displaced toward the outer side so that it overlaps the front of the radius and its axis is directed toward the middle of the hand. The diagnosis is easy, but search should be made, as in the preceding variety, for the possible coexistence of a fracture of the radius. The best method of reduction appears to be by direct pressure upon the ulna and counter-pressure in the radius. Dislocations inward and downward (Fig. 97) have been observed only in connection with fracture of the radius or, very rarely, with dis Fracture of the radius and ulna: displacement upward of the lower fragment of the radius. (MALGAIGNE.) location of its upper end, and are to be deemed complications or incidents of the other and more important injury. 1 Valleteau: Gazette Médicale, 18-6, p. 250. In like manner, the serious complication of perforation of the skin. by the ulna has occurred only once except in connection with fracture of the radius. of Pathological dislocations have been reported as the consequence chronic suppurative arthritis and also of non-suppurative arthritis provoked by a sprain or by a fracture of the radius. Possibly the case reported by Rognetta' of a negro who suffered from an habitual dislocation backward gradually produced by the effects of his occupation as a woodsawyer belongs in this category, the ligaments having become relaxed in consequence of an arthritis set up by the constantly repeated mechanical violence of the movement. B. DISLOCATIONS OF THE RADIO-CARPAL JOINT. These dislocations, long thought to be common because fracture of the lower end of the radius was habitually supposed to be a dislocation until Dupuytren forced a recognition of the error, are now known to be of infrequent occurrence. Dupuytren, in the vigor of his correction of the error, went to the other extreme and pronounced them unknown or of very great rarity, and this assertion has colored the general opinion concerning their frequency even to the present time. The statistics that have since been collected are not entirely trustworthy, perhaps, for the error in diagnosis appears still to be made and all reported cases cannot be unhesitatingly accepted, but there is reason to think that the rarity is not very great, and there are enough well-authenticated cases to make it possible to trace a general description of the injury. Malgaigne collected 14 cases, 8 of backward, 6 of forward dislocation. Parker collected 33 cases, 23 backward and 10 forward. Tillmanns (loc. cit.), 1874, collected 24, 13 backward and 10 forward; and Serviers in 1880 collected 26 besides 1 observed by himself, 13 backward, 13 forward, and 1 outward, of which about 19 were not contained in Tillmanns's paper. I have found 13 cases published since 1880 and have myself observed 1, 12 backward and 2 forward, and it is worthy of note that 5 of these were reported in the British Medical Journal within six weeks of one another, March and April, 1880, the reports of the last 4 having been called out by that of the first. In addition, Albert speaks of 5 within his knowledge or observation. Even supposing Parker's 33 to include all of Malgaigne's and Tillmanns's, and counting 19 of Servier's, this would still give a total of about 70 cases more or less well authenticated, the correctness of the diagnosis in a number of them being entirely beyond question. The necessity of receiving with some caution those cases that have been observed clinically and reported with scanty detail is shown by the errors in diagnosis that have been made by experienced surgeons fully aware of the difficulty. Malgaigne (loc. cit., p. 703) narrates three striking cases. At the time when Dupuytren was first questioning the 1 Rognetta: Archives gén. de Méd. 1834, vol. 5, p. 396. 2 Parker: Trans. South Carolina Med. Assoc. Abstract in N. Y. Med. Record, 1871, vol. 6, p. 396. 3 Servier: Gazette Hebdom., 1880, p. 211. correctness of the diagnosis in which fracture of the lower end of the radius was habitually taken to be a backward dislocation of the wrist, a patient presenting all the usual signs of this injury died at the Hôtel Dieu. Pelletan declared it to be a dislocation, Dupuytren a fracture, and the former did not vary from his opinion until after the last stroke of the scalpel had exposed the bone and showed the injury to be a fracture with crushing of the lower end of the radius. In 1834 Roux made the diagnosis of dislocation backward in the case of a child that had fallen from a tree; again dissection proved it to be a fracture, with separation of the epiphysis. Still more remarkable was a case reported by Chassaignac in which he excised the projecting ends of the radius and ulna, thinking the case was dislocation; on careful examination it proved to be a separation of the epiphysis of the radius. The difficulty is probably not so great in dislocations of the carpus forward. The dislocation may be complete or incomplete backward or forward, and in one case was incomplete outward; it may be simple or compound, or associated with fracture of the radius or ulna. Apparently fracture of the edge of the articular surface of the radius on the side toward which the carpus is dislocated is not infrequent; such fracture of the posterior lip of the radius is known in this country as "Barton's fracture," but it appears to me properly to belong among the dislocations, the fracture being only an incident or complication. The incomplete dislocations are mainly those in which only the outer portion of the carpus, the scaphoid and semilunaris, are dislocated from the radius, while the inner portion maintains its relations with the triangular fibrocartilage and ulna; this variety appears to be produced by a movement of rotation (pronation or supination) in which either the radius or the carpus is kept stationary while the other moves away from it; it appears to be sometimes associated with disturbance of the relations of the lower radio-ulnar joint. In addition to the traumatic, a few pathological and congenital dislocations have been reported. 2 Dislocations backward.—The causes of this dislocation are characterized by great violence, as a fall from a height upon the palm of the hand; in some cases the wrist appears to have been flexed forward, "doubled under" the patient, in a fall while walking, or from a slight elevation: and in one case, Chapplain, the injury appears to have been caused by direct violence, the wrist having been caught between the buffers of two railway cars. In the first form it appears probable that the anterior ligament yields, and that then the carpus slips backward upon the radius and ulna; in the second, the posterior ligament must be the first to rupture. In two almost identical cases, Billroth, Rydygier, the mode of production is clearly shown: in the former, the patient, while pressing with the palm of his hand against a railway car in an effort to arrest its motion, was struck upon the back of the elbow by another car moving in Chassaignac Bull. de la Société de Chir., 1868, p. 225. : 2 Chapplain: Bull. de la Soc. de Chirur., 1874, vol. 3, p. 461. Billroth: Arch. für klin. Chir., vol. 10, p. 601, quoted by Tillmanns. the opposite direction, and a compound dislocation of the wrist was produced, the articular surfaces of the radius and ulna projecting through the skin on the palmar surface. Rydygier's patient was caught in the same way between a wagon and a wall, alongside of which it was moving. The pathology is illustrated by a number of post-mortem examinations, and by some cases complicated by wounds which permitted direct examination of the joint. The autopsy that has been reported with most detail is that of a case observed by Voillemier. The patient was a man twentyseven years old, who had fallen from the third story of a building, and received injuries which caused his death in four hours. The violence that caused the dislocation of the wrist was apparently received upon the palm of the hand while in dorsal flexion. The external and posterior ligaments were ruptured, the anterior was torn away from the radius, and the internal was intact but was separated from the ulna by avulsion of its styloid process. The tendons and muscles of the back of the forearm were not torn, but had been stripped off the radius, bringing with them the periosteum and small pieces of attached bone. The superficial flexor muscle was widely perforated and torn by the styloid process of the radius at its inner portion, that corresponding to the tendons of the ring and little fingers, the remainder being pushed to the outer side together with the median nerve and radial vessels. In Servier's case, a man twenty-five years old, the ligaments were extensively torn, except those portions which bind the semilunar to the radius; all the ligaments that attach the semilunar to the scaphoid, os magnum, and cuneiform were torn, and the latter bone was in addition almost completely separated from the unciform and was fifteen millimetres distant from the styloid process of the ulna. The carpus, with the exception of the semilunar which remained solidly attached to the radius, was displaced backward about one centimetre; the radio-ulnar ligament was intact, and there was no fracture of any of the bones. The injury was caused by a fall from a great height in which the skull also was broken, the patient dying a few hours later. Paret's patient was a sailor who had received his injury in a fall from a yard to the deck; the entire anterior lip of the radius projected through the skin; the tendon of the flexor longus pollicis was torn, and the ulna broken in its lower third. In a case reported by Colgate there was a transverse wound of the skin on the front of the wrist, which apparently was not deep and did not communicate with the joint. In a case reported by Marjolin (quoted by Servier), in which the dislocation was made compound by a wound at the level of the lower end of the radius and the patient died of purulent infection, the anterior and external ligaments were torn; the bones were intact. In an old case dissected by Padieu (quoted by Servier) the first row of the carpus rested on the back of the radius. In Lenoir's case a narrow fragment of the posterior articular border 1 Voillemier: Arch. gén. de Méd., 1839, vol. 6, p. 401. 2 Paret: quoted by Servier and Tillmanns. Colgate: Lancet, 1873, I., p. 697. of the radius had been broken off; it remained attached to the capsule and was displaced backward with the carpus. This is the so-called "Barton's fracture of the radius" (see Fractures, p. 453). In no other autopsy of a backward dislocation has this fracture been reported, but it has been suspected to exist in some of the cases observed clinically, and a few specimens of the reunited fracture without history are in existence. In a case quoted in the Centralblatt für Chirurgie, 1884, page 279, both styloid processes were broken. Of the incomplete form, that in which only the outer portion of the carpus is dislocated, the only case given in sufficient detail is that of Dupuy the patient, a young and muscular porter, while trying to lift a cask had his hand forcibly supinated while the radius remained pronated. On examination two hours later the hand was found flexed and half supinated, while the radius was pronated. Both styloid processes could be distinctly felt, that of the ulna in its normal relations with the carpus, but that of the radius and the articular surface of the latter projecting as a ridge on the posterior aspect of the wrist. Fifteen millimetres above the posterior margin of the end of the radius was a rounded bony prominence, highest on the outer side and gradually diminishing toward the ulna. No crepitation; no shortening of the limb. Reduction was effected by traction and direct pressure. In short, the dislocation is habitually accompanied by an extensive laceration of the ligaments, especially the anterior and external; avulsion of the posterior lip of the articular surface of the radius may take the place of rupture of the posterior ligament. The extensor tendons are lifted from their grooves but not torn; the flexors may be torn or pushed to the outer side by the projecting radius; the median nerve and radial artery have always escaped injury, even when the radius has been driven through the skin. The carpus may be displaced directly backward so as to rest upon the posterior surface of the radius, without FIG. 98. Dislocation of the carpus backward. (FERGUSSON.) change in the relations of the several bones that constitute it, or with more or less separation of them from one another, the semilunar bone in 1 Dupuy Journ. de Bordeaux, July, 1850, quoted by Tillmanns. |