The diagnosis is not difficult; and as reduction is usually easy the prognosis in simple, uncomplicated cases is good; but attention should always be paid to the presence or absence of pulsation in the distal branches of the artery, both before and after reduction. In some reported cases in which the dislocation has remained unreduced, the patient has had good use of the limb. Two such are the cases of Bagnall-Oakeley' and Karewski.2 The former's patient was a man, seventy years old, who had dislocated his left knee at the age of nine months; he had always made full use of the limb, and had earned his living as a brickmaker. A false joint had formed between the femur and tibia, which permitted 15° of flexion. The foot and leg were normally developed; the thigh had an abnormal anterior curvature. The patella could not be recognized, and was thought to have become united with the femur. The different prominences of the lower end of the femur were absolutely subcutaneous and seemed ready to perforate the skin, but there was no trace of previous ulceration. Karewski's patient was a servant girl, thirty-two years old, whose dislocation had existed for more than sixteen years. The right limb presented a typical dislocation backward, and when viewed from behind looked like a genu recurvatum, while when seen from in front and the side the thigh overhung the leg to a certain extent. The muscles of the calf were somewhat atrophied; the nerves and vessels stretched above the tibia like tense cords. The growth of the bones had been materially affected, the tibia being three centimetres shorter than the other, and also thinner; while the femur was lengthened by three or four centimetres. The overriding of the tibia and femur was four centimetres. Flexion and extension were normal, both actively and passively, and although there was much lateral mobility the functions of the limb were admirably performed. Pain was felt only after exceptional use. In Lossen's case, in which reduction was attempted at the end of six weeks and failed, the patient finally walked well; extension was complete; flexion to a right angle. The rupture of the external lateral ligament resulted in the production of a genu varum. Treatment.-Reduction, which is usually easy, has been effected by traction with coaptative pressure upon the adjoining ends of the femur and tibia and flexion of the knee and hip. In some cases flexion alone has been sufficient. In Testut's case, in which the femur was broken just above the condyles, reduction was made by traction under anesthesia. Spence successfully treated an irreducible dislocation by open. arthrotomy. The patient was a man, sixty years old, who had received the dislocation March 15, 1876, two days before admission to the hospital. After a failure to reduce under anaesthesia, continuous traction with a weight of sixteen pounds was made for three days, and then a second. unsuccessful attempt was made. March 22d, traction with pulleys having also failed, the joint was opened by a curved incision below the patella; it was found filled with clots, the internal lateral ligament broken, and the posterior part of the internal semilunar cartilage displaced. After division of the external lateral ligament and the tendons of the hamstring muscles, the dislocation was easily reduced. The wound was drained and dressed antiseptically, the limb placed on a long posterior splint, and continuous traction made with a weight of eight pounds. As the lower end of the femur tended to project anteriorly, pressure was made upon it in front. The traction was maintained until June 15th, and when the patient was last seen, September 13th, the limb promised to be very useful. In compound dislocations, and in those complicated by injury to the main vessels and nerves, the principles of treatment are the same as in dislocations forward. LATERAL DISLOCATIONS. Lateral dislocation, more rare than either of the preceding varieties, may be outward or inward, complete or incomplete, simple or compound. The outward form is more common than the inward. The term subluxation has been applied to those cases in which the displacement is slight. A. Outward dislocations. Of the complete form of this dislocation Malgaigne could find only one recorded case, and that a doubtful one; but, since the publication of his work, von Pitha' has reported two cases in which the dislocation was nearly, perhaps quite, complete; and Hughes has since published a third. Von Pitha's first patient was a young woman who, while carrying a heavy basket on her back, suddenly doubled up under it. The right tibia was so completely dislocated outward that its entire upper articular surface stood out free, so that von Pitha could easily lay four fingers upon it. The skin was tightly and smoothly stretched over the articular surface, and was continuous at a sharp angle with that of the side of the thigh; the edge of the tibia threatened to cut through the tense, thin skin, and in like manner the internal condyle of the femur projected abruptly over the leg. The patella was displaced outward, and was placed obliquely, almost transversely. Reduction was extraordinarily easy. The reaction was so slight that the patient left the hospital on the next day. His second patient was a robust young man who received his injury by springing to the sidewalk from an overturning wagon. The appearance of the limb, when seen immediately after the accident, was the same as in the other case, except that, if possible, the edge of the tibia had more nearly cut through the tense, white skin. The flat upper surface of the tibia stood out so free beside the femur that an ordinary goblet could have rested on it. Reduction was easily made, and the intense pain at once ceased. The patient refused to remain in hospital, saying that he felt able to walk, if necessary. In Hughes's case the injury was not compound, but the skin was much 1 Pitha and Billroth: Chirurgie, vol. 4, part 2, B., p. 258. Hughes Lancet, 1880, ii. p. 974. stretched. Reduction was easy. The patient had fallen thirty feet and died within twenty-four hours. In the incomplete form only a part of the head of the tibia, usually all the outer half, projects beyond the side of the external condyle of the femur. The commonest cause is outward flexion of the knee, abduction, produced by a fall upon the foot or by the pressure of a heavy weight upon the posterior, or by a blow upon the outer, side of the knee; in the latter case the blow is probably received upon the lower end of the femur and not upon the tibia. A rarer cause is direct violence acting transversely upon the outer side of the lower end of the femur or the inner side of the head of the tibia without causing lateral inflection (Annandale). The mode of production appears to be rupture of the internal lateral and perhaps of the crucial ligaments by abduction of the leg, followed by the lateral gliding of the articular surfaces. The only reports of direct examination of the injured joint are furnished by Hargrave' and Bonn, quoted by Malgaigne, and by Wells.2 Hargrave's patient died on the fifty-third day, after suppuration of the joint; the internal lateral ligament was completely ruptured, the external partly torn; the anterior crucial torn across, the posterior crucial and the ligaments of the patella intact. Bonn's was an old unreduced dislocation; he says all the ligaments were intact and that the external condyle of the femur rested upon the crest of the tibia. In Wells's case a large scale of bone was torn from the inner side of the internal condyle, the patient died on the fourth day in consequence of gangrene of the limb. Instead of being directly outward the displacement may also be somewhat backward or forward. When compound, the wound has always been on the inside. In one compound case, Notta,3 the popliteal artery was ruptured and the patient died after amputation. The symptoms are more or less marked in accordance with the degree of the displacement; the internal condyle of the femur projects more or less markedly on the inner side, and the outer part of the head of the tibia on the outer side; and the greater the displacement the more likely, according to Malgaigne, is it that the outer part of the tibia will be rotated backward. The displacement outward of the patella shows corresponding variations in degree; it may be simply inclined, so that its vertical axis is directed downward and outward, or it may be carried to the outer side of the external condyle. The leg may be flexed or extended, and is usually adducted, but may be widely abducted (Fig. 153); voluntary movements are generally impossible. The prognosis does not differ materially from that in the two preceding forms; but it is worthy of note that in a case seen six years after the accident by Desormeaux (quoted by Spillmann) the leg was permanently abducted 45°, presumably the consequence of failure of repair of the internal lateral ligament. In another, reported by Morgan, in which the 1 Hargrave: Dublin Quart. Journ. Med. Sci., 1850, vol. 9, p. 473. 2 Wells: Am. Journ. Med. Sc., 1832, vol. 10, p. 25. Notta: Annales Méd. des Calvados, 1876, quoted by Poinsot. dislocation had remained unreduced for three and a half years, the limb could be flexed to a right angle but could not be voluntarily extended, so that the patient fell whenever the leg became at all bent while he was standing upon it. FIG. 153. INI Robert's case of dislocation of the knee outward, with abduction. In one reported by Dr. W. T. Bull (N. Y. Med. Journal, Jan. 1885), and shown to the N. Y. Surgical Society three years later (Jan. 1888), the recovery was absolutely complete. Treatment. Reduction, generally very easy, is effected by traction and direct coaptative pressure upon the ends of the bones. It is very important that the limb should be immobilized for a long time after reduction in order that the torn ligaments may solidly reunite. Probably it would be well to keep the limb for three or four months in a firm dressing which would keep it extended and prevent lateral bending. Passive flexion and extension might be systematically employed during much of this time if loss of normal mobility were feared. In a case reported by Braun' of incomplete outward dislocation which proved irreducible arthrotomy was done. The patient was a man fortyfour years old; the leg was rotated inward and abducted at an angle of 145°; the internal condyle of the femur was prominent, and a small movable piece of bone could be felt below its inner side. "A curved incision eight centimetres long was made parallel to the internal condyle.' The small piece of bone proved to be the detached internal tuberosity. The internal condyle filled the rent in the capsule so closely that only after a long search could a small opening be found below it through which the tip of the finger could be passed into the joint; it was slightly enlarged with the knife, and then reduction was easily made. The patient made a slow recovery, and the joint remained stiff. The treatment of compound dislocations and of those in which the artery has been torn is the same as in forward dislocations (q. v.). 1 Braun Deutsche med. Wochenschrift, 1882, p. 291. : B. Inward dislocations. These also may be complete or incomplete, simple or compound. Of the complete form there are only two cases on record, Miller and Hoffmann,' and Galli, both quoted by Malgaigne. The first was a man twentyeight years old who while getting into a carriage caught his leg between the spokes of the wheel and could not free it before the horses started. The femur was completely separated from the tibia and projected outward and downward, the external condyle presenting through a wound in the skin three inches long. Through this wound the joint and the uninjured popliteal artery could be seen. Reduction was made at once without difficulty; four months later the wound had closed and the patient walked with crutches. A month later he could walk well without aid. Galli's patient, a very muscular young man, was thrown from a horse, striking upon the right foot with the limb abducted, the knee bent and carried at the same time forward and inward. The lower end of the femur had almost entirely passed through the soft parts on the outer side; the ligamentum patella was ruptured. Reduction was made and the patient recovered. Two years later he could ride on horseback, but the knee was subject to become inflamed and also to frequent displacements which had to be guarded against by wearing a brace. The causes of the incomplete form are similar to those of the outward dislocations: lateral flexion of the knee or a blow upon the outer side of the tibia or on the inner side of the condyle of the femur. In a case quoted from Cooper by Malgaigne (loc. cit., p. 960) in which there was also rotation inward of the tibia, the soft parts covering the external condyle of the femur behind and externally had been ruptured. The limb was amputated, and dissection showed a large rent in the vastus externus immediately above its insertion upon the patella; posteriorly the capsule and gastrocnemius were torn; the lateral and crucial ligaments were intact. The symptoms of the incomplete form are the projection of the head of the tibia on the inner side and of the external condyle of the femur on the outer side. The leg may be inclined outward or inward, rotated inward, and more or less flexed. Reduction appears always to have been effected without much difficulty by traction and coaptative pressure; and the only special feature in the prognosis arises from the rupture of the internal lateral ligament, for if its repair is not thorough, or if the limb is prematurely used, the leg tends to deviate outward (knock-knee) under the weight of the body. It would, therefore, be advisable to support the joint for a long time by means of a brace. ANTERO-LATERAL dislocations constituted in Malgaigne's classification a separate class of very rare occurrence, the tibia being displaced forward and outward. Of the latter form he found only one recorded example and that a doubtful one. In the very rare examples of dislocation forward and inward no special features appear; and the same may be said 1 Miller and Hoffman: London Medical Repository, 1825, p. 346. |