Emergency Management of Major Injuries of the Extremities

Emergency Management of Major Injuries of the Extremities OSCAR P. HAMPTON, JR., M.D., F.A.C.S.

A MAJOR injury of an extremity is one which, unless given precise surgical management, will result in significant impairment of function or perhaps loss of the limb. Major extremity injuries include open and many closed fractures of the long bones, open wounds of joints, dislocations of major joints, lacerations of major peripheral blood vessels or nerve trunks, and massive wounds of skin and muscle. For this discussion major injuries of the extremities include only open and certain closed fractures of the long bones, open wounds of joints, and dislocations of major joints, including massive ligamentous tears. The other major injuries just listed are discussed in detail elsewhere in this volume. FIRST-AID MEASURES AT THE SCENE OF THE ACCIDENT (OR LATER)

Significant first-aid measures include the application of dressings to wounds, the arrest of hemorrhage by compression dressings or, rarely, a tourniquet, and adequate emergency splinting for fractures. The physician who first treats the casualty, whether at the scene of the accident, in his office or in the emergency room of the hospital, is obligated to see that these measures are effectively carried out. In no other group of injuries are first-aid measures more important. A sterile or merely clean dressing prevents further contamination of a wound and tends to stop bleeding. A compression dressing or, when necessary, a tourniquet may prevent loss of life from hemorrhage. Effective emergency splinting of fractured extremities minimizes discomfort, prevents further damage to soft parts, tends to prevent or overcome shock, may avoid delayed compounding of a fracture, and prepares the patient for safe and comfortable transportation. Indeed, what is feasible as definitive surgery fOf From the Department of Surgery, Washington University School of Medicine, St. Louis, Missouri. 1261

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the injury and the eventual end result may depend largely on the quality of first aid rendered the patient by the physician. Emergency Splinting

It is essential to distinguish splinting applied for a limited time for transportation from splinting to achieve or hold reduction of a fracture and provide prolonged immobilization. An adequate transportation

Fig. 446. Splendid emergency splinting for fractures of the humerus. A sling supports the forearm. A bandage of split stockinette holds the arm firmly to the chest wall. Actually, the vertical turns are not necessary.

splint prevents additional soft part injury and further deformity. It must not, in itself, cause nerve injury or pressure sores or jeopardize the circulation of the extremity. Emergency splinting of fractured extremities may be provided by standard splints and methods, or it may be improvised. The use of standard splints, while highly preferable, is often not feasible. Since improvised splinting can be made effective, the lack of standard splints in

Emergency Management of Major Injuries of the Extremities 1263 no way relieves the physician of his obligation to provide effective emergency splinting for fractures of the extremities at his first opportunity. Upper Extremities. Adequate splinting of injured upper extremities is seldom a problem. For injuries distal to the elbow a cock-up or a board splint is desirable, but is really essential only when both bones of the forearm are completely broken. For injuries above the elbow the position of the arm at the side, with the elbow flexed about 90 degrees, is by far the most comfortable. Adequate splinting in this position is easily provided by the use of a sling to support the forearm and by binding the arm to the chest with another sling serving as a swathe or with several turns of a roll of bandage (Fig. 446).

Fig. 447. Fixed traction in a hinged half-ring splint is probably the best emprgency splinting for a fracture of the femur or of both bones of the leg. Note that the traction hitch is over the shoe, which is not removed, and that the end of the splint is elevated.

The full-ring hinged arm traction splint, often recommended in old texts, is mentioned only to condemn it. It has no place in the emergency splinting of injuries of the upper extremity. During W orId War II it was found to be totally unsuited for emergency splinting, and it has been discarded for this purpose by the military. Lower Extremities. The most effective emergency splinting is that provided by fixed traction in standard Thomas or hinged half-ring splints (Fig. 447). Care must be taken to make certain that the traction hitch about the foot and ankle does not cause excessive pressure on the dorsum of the foot. To that end the traction hitch may be applied over the shoe, which is not removed. Only moderate traction is necessary.

Oscar P. Hampton, Jr. Improvised splinting, while not ideal, can be highly effective. For fractures of the femur at any level and really for fractures of the tibia at the knee the ideal improvised emergency splinting consists of three board splints well padded. Posterior and medial padded boards extend from the upper thigh, and a lateral padded board extends from the axilla to the foot. The latter is securely bound not only to the extremity, but also to the abdominal and chest walls (Fig. 448, A). For fractures of the lower two-thirds of the leg two or three padded coaptation board splints extending from the upper portion of the thigh to

B A i:iFig. 448. A, Coaptation emergency splinting for a fracture of the femoral shaft. A posterior board is not visible. The lateral board passes above the costal margin and is securely bound to the trunk. B, Coaptation emergency splinting for a fracture of both bones of the leg. The posterior and medial boards are not visualized. It is important that the physician test for adequate arterial pulsations in the foot after the splinting has been provided.

below the foot provide effective splinting (Fig. 448, B). Also, the pillow splint, in which a pillow provides the padding while posterior, medial and lateral boards provide the immobilization, is highly effective emergency splinting for fractures of the leg. For fractures about the ankle a pillow bound snugly to the leg and foot may often furnish adequate splinting. When board splints are applied to the lower extremity, sufficient padding, properly arranged, must protect the malleoli and also the head of the fibula to avoid pressure on the peroneal nerve which could cause peroneal paralysis. OPEN FRACTURES

An open wound communicating with a fracture site is hazardous for many reasons, but principally because of the danger of secondary infec-

Emergency Management of Major Injuries of the Extremities 1265 tion and failure of the wound and fracture to heal. An infected open fracture is serious for many reasons. Nonunion may follow. Massive sequestration of bone may take place. Adjacent joints may be destroyed. Infection may endanger life or limb. At best, wound healing is slow and is accompanied by excessive scar formation. These potential dire consequences demand that all efforts in the management of open fractures be directed toward the rapid healing of open wounds without infection as well as toward the healing of the fracture in good position. Infection in the compounding wound may be a true invasive infection taking origin in dead and devitalized tissue. More commonly, infection results from bacterial decomposition of dead tissue and blood clot with resulting suppuration. The purulent collection leads to further destruction of tissue with more suppuration: In other instances a suppurative process is not present in the beginning, but the open wound leaves bone or fascial-tendinous structures exposed. Those tissues, which cannot survive exposed soon die with resulting wound suppuration. Exposed bone or fascial-tendinous tissue is, then, tantamount to dead tissue in the wound. The common denominator in all these wound infections is dead and devitalized tissue. The basic principles of management of open fractures call for the surgical elimination of this pabulum of sepsis. First-Aid Treatment

This consists in the application of a sterile dressing and proper splinting. Antiseptics are definitely contraindicated. Protruding fragments of bone should not be replaced in the wound, but should merely be covered with the dressing. It follows that in applying fixed traction in emergency splinting the amount of traction should not be sufficient to cause protruding fragments to recede into the depths of the wound. Immediate hospitalization is indicated. Antibiotics and appropriate antitetanus prophylaxis should be initiated promptly. Definitive Treatment

Open fractures deserve prompt, thorough investigation, apprasial and treatment in a well equipped operating room. The emergency room is no place for evaluation of an open fracture. After adequate treatment of hemorrhage or wound shock, with adequate roentgenograms visualizing the entire length of the broken bone, and with the patient under adequate anesthesia the open wound is thoroughly examined. Appraisal of the amount of retained dead tissue and the degree of the contamination of the wound determines what surgery is indicated. Wound Debridement. Exposure of the depths of the wound must be adequate. Inadequate exposure leads only to inadequate debridement. Usually the wound must be extended in the directions affording the best access to the depths and still permitting closure by suture. Contrarily,

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unnecessary exposure of tissues likely to die, if they remain uncovered, is avoided. An incision should not cross the center of a wound running in the opposite direction, since this would create a crucial incision. Rather, proximal and distal incisions from a transverse or circular wound should begin at opposite corners of the wound so as to leave in effect a Z-shaped incision which facilitates later repair by suture. After ample skin incision dead and/or devitalized tissue is excised. Healthy muscle is not discolored, bleeds freely and contracts when pinched; muscle not meeting these requirements warrants excision. Foreign bodies and dirt are removed. Thorough irrigation is a valuable cleansing method. Small bone fragments completely free of attachment are excised; fragments which have any soft tissue attachment are carefully preserved. Sponging at the fracture site is done with great care to avoid avulsing jagged fragments, which easily catch in the meshes of a sponge. Wound Closure. The decision to suture the wound immediately requires sound surgical judgment. An immediate successful suture of the wound is most advantageous, but an unsuccessful suture, because of abscess formation or necrosis of skin margins from excessive tension, is worse than if the wound had been left open to granulate to healing. Either of these complications causes additional soft tissue necrosis which further retards and may prevent healing of the wound. Primary suture of clean, well debrided wounds of open fractures is usually feasible, particularly within 12 to 16 hours after injury, provided closure is surgically feasible without excessive tension both at the time of the closure and later after swelling of the wound margins has occurred. Conversely, when the surgeon cannot be sure that the wound is free of the pabulum of sepsis or if closure by suture might lead to excessive tension, an open wound is highly preferable despite its inherent hazards. Frequently, excessive tension can be eliminated by long full-thickness relaxing incisions parallel to, but several inches from, the suture line. If for good cause the wound is left open, delayed closure between the fourth and seventh days is indicated if surgically feasible and the wound is clinically clean. Delayed closure of clinically clean wounds is indicated, provided dead space is obliterated or dependently drained and excessive tension is avoided. The problem of surgical closure, primary or delayed, of an open wound of a fracture versus the advantages of an open wound for drainage as a safeguard against deep infection is one that may severely tax the judgment of even the most experienced surgeon. COMMENT. Do all open fractures require wide debridement? Undoubtedly in many, usually those opened from within-out, the surgeon can be reasonably certain from the circumstances"o(the accident, the appearance of the wound and the appearance of the clothing about the site of injury that no foreign material has been carried into the wound

Emergency Management of Major Injuries of the Extremities 1267 and that soft tissue damage is negligible. Under these circumstances the surgeon may elect to irrigate the wound thoroughly with sterile saline solution, suture the skin margins, or merely apply a pressure dressing and reduce and immobilize the fracture. Such practices are calculated risks. In a majority of open fractures some debridement of the depths of the wound is definitely indicated. Management of the Fracture. The same methods of management are applicable in general to open as to closed fractures. In the former, however, the question of internal fixation assumes paramount importance at the time of debridement of the wound. If the contour of the fracture permits adequate stabilization by the usual internal fixation techniques, this method is usually considered. This, too, is a problem that requires expert decision. Practically, in well debrided wounds which permit closure by suture or in which heavy masses of muscle tissue will fall over and protect bone and metal from exposure, indicated internal fixations are permissible. Methods which require little or no periosteal stripping such as intramedullary or multiple screw fixation appear highly preferable to plating. On the other hand, when factors which predispose to infection are present, internal fixation is probably too hazardous. In doubtful instances it is preferable to use some method of management of the fracture other than internal fixation and direct all efforts toward wound healing. Then, if adequate reduction of the fracture has not been maintained, internal fixation may be performed through an intact skin envelope. However, an adequately stabilized fracture in good position actually may favor rather than retard wound healing. Moreover, with the fracture stabilized in reduction, staged wound care is possible without fear of loss of position. In summary, the basic principles of the management of open fractures are (1) proper first aid, sterile dressing and effective emergency splinting; (2) proper treatment of the effects of hemorrhage and wound shock; (3) prompt debridement of the wound, according to indications, in the operating room, not in an emergency room, (4) proper selection of the method of management of the fracture) using internal fixation only as a calculated risk; (5) primary or delayed closure of the wound according to surgical limitations; (6) antibiotics administered systemically as a safeguard against invasive infection of living tissue by bacteria presumed to be present in every traumatic open wound. CLOSED FRACTURES

Space limitations dictate that any consideration of closed fractures be limited to a few statements concerning the selection of the proper method of management for certain complicated fractures. Each entity discussed is meant to be one of considerable magnitude requiring special skill and measures for proper treatment.

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Every method which a surgeon may select for any of these injuries may be classified as (1) closed reduction followed by immobilization, usually with a plaster cast, (2) continuous traction, usually skeletal, and (3) open reduction with internal fixation. Each of these methods offers certain advantages and disadvantages for varying problems. The choice of method depends upon a number of factors, including the contour of the fracture, the condition of the skin overlying the fracture, the general condition of the patient, the skill and experience of the surgeon in the several methods of management, and the equipment available. In fractures of the upper extremities the surgeon must constantly keep in mind that the most important consideration is the preservation or restoration of the function of the hand. Solid bony union of the fracture in good alignment with preservation of the motion of all the joints above the hand is highly desirable, but in the attempt to achieve this the ultimate function of the hand must not be jeopardized. It is far better to accept some bony deformity and even some restriction of motion in joints above the hand and still preserve all its function than to obtain perfect bony alignment and full motion of the major joints at a premium of impaired hand function. In the lower extremity, on the other hand, the objective is to obtain a healed fracture which permits painless, stable weight bearing. Movable jointlil for locomotion and full length are highly desirable, but even these take second place in importance to a pain-free, stable extremity which will amply support the weight of the body. Moreover, full length is not essential for excellent function, and often it is preferable to insure excellent contact of fragments at the price of some shortening in preference to overcoming all shortening at the risk of distraction and nonunion. Fractures of the Shaft of the FeIllur

Open reduction and internal fixation by intramedullary nailing has been established as the preferable method of management for this severe skeletal injury, provided the nail will adequately stabilize the fragments. The nail must be strong and straight and fill the medullary canal as much as possible. To that end, reaming of the medullary canal, particularly at the junction of the upper and middle thirds of the femoral shaft so as to permit the use of a larger-diameter nail, is an important step in the technique. The Kuntcher cloverleaf nail is recommended as the best available nail for intramedullary fixation. Intramedullary nailing for transverse and near-transverse fractures of the middle three-fifths of the femoral shaft is generally accepted. The tremendous advantages of this method of management over all others should be extended whenever possible and practicable to comminuted fractures within the same levels. The judicious use of tangential screws,

Emergency Management of Major Injuries of the Extremities 1269 circumferential loops of stainless steel wire or Parham-Martin bands to stabilize comminuted fragments as a supplement to the fixation provide by the intramedullary nail will often achi.eve the objective of a stable fixation so that external immobilization is not necessary (Fig. 449). T -Fractures of the Lower End of the Femur

These complicated fractures can often be stabilized in good reduction so as accurately to restore and maintain the articular surface of the femur by open reduction and internal fixation with a blade plate. The Moore or

B A Fig. 449. A, Comminuted oblique fracture of the femur at the junction of the middle and lower thirds. Ordinarily the advantages of intramedullary fixation are not extended to such a fracture. B, This severely comminuted fracture was adequately stabilized with an intramedullary nail and 2 Parham-Martin bands. External immobilization was not necessary. The fracture proceeded to solid union within a reasonable period of time. The Parham bands were removed after x-ray evidence of union of the fracture was visible.

Blount hip nails, properly molded, are splendid for this purpose, although special blade plates designed for this injury are available. In the Tfracture with widely separated condyles, better exposure at operation can be obtained for accurate reduction of the condyles if, as part of the operative exposure, the patella ligament is severed. Of course it must be accurately repaired. It will heal before the fracture is united. The condyles may be first stabilized in reduction by means of a tibial bolt; then the blade plate can be inserted more easily and accurately. At times the bolt may be removed after the blade plate fixation has been obtained, or it may be left in place and removed under local anesthesia at a later . operation (Fig. 450).

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Fractures of Both Bones of the Leg

r:Closed reduction and immobilization is adequate for these injuries only when a stable reduction can be obtained and maintained. A really stable reduction is possible as a rule only in transverse or near-transverse fractures of the tibia. For those fractures which do not permit a stable manual reduction some form of internal fixation is highly desirable and should be~provided unless local condition of the skin or the general condition of the patient contraindicates it.

Fig. 450. T-fracture of the distal end of the femur treated by open reduction and internal fixation with a blade plate. The ordinary Moore hip nail, properly molded, was used.

Intramedullary nailing is a highly efficient method for many fractures of the tibia. For this purpose the Lottes triphlanged nail is the most advantageous. In a great majority of fresh or recent fractures the nail may be inserted "blindly," thereby avoiding an incision over the fracture site.IThe nail is inserted high on the tibia just medial to the patellar tendon and driven down the canal just short of the level of the fracture. The latter is then manipulated into reduction and held while an assistant drives the nail across the fracture site and into the distal fragment. At this point check x-ray films confirm that the point of the nail has entered

Emergency Management of Major Injuries of the Extremities 1271 the distal fragment and is passing down the medullary canal. Minor errors in alignment can easily be corrected. The nail is then driven home. It should extend to within 1 inch of the ankle joint. An important advantage of this nail is that it if) sufficiently soft to permit it to be bent at the fracture site by manual force so that any malalignment, which is occasionally obtained, may be immediately corrected. As a general rule, a long leg plaster cast for external immobilization is necessary. The objective of intramedullary nailing of fractures of the tibia is not to eliminate the necessity for a plaster cast. Its chief advantages are that it can be inserted "blindly," thereby avoiding open exposure of the fracture site with its inherent dangers of infection or poor wound healing, and that it does maintain adequate apposition and alignment of the fragments while still permitting constant contact compression of the fragments which predisposes toa rapid and high rate of union of the fractures. WOUNDS OF JOINTS

Any wound which involves a joint is a serious wound. The damage at wounding, however slight, immediately prejudices the subsequent function of the joint. Of even greater importance, every wound of a joint is a potential site of suppurative arthritis. If that process becomes established, all function of the joint may be lost, and, especially if the affected joint is in the lower extremity, life as well as limb may be endangered. An open wound of a joint is a true surgical emergency which warrants thorough investigation in the operating room under anesthesia. The principles of debridement of wounds are interpreted to include an adequate arthrotomy sufficient to permit removal of all foreign bodies and material and devitalized areas of articular cartilage resulting from trauma or superimposed suppuration. The joint is opened to the extent and in the area which best provides access to the interior of the joint and the site of possible articular cartilage damage. Occasionally enlargement of the traumatic wound is sufficient for this purpose, but often a standard arthrotomy incision is necessary. Loose chips of bone and all exudate in the joint should be removed, followed by thorough irrigation of the joint cavity. Then the synovial membrane, perhaps with the capsule, is closed by suture. The skin mayor may not be sutured, depending upon the degree of destruction of tissue and contamination. After closure of the joint-for obvious reasons not before-50,OOO to 100,000 units of penicillin in 5 to 10 cc. of saline solution are instilled into the joint cavity. After operation adequate immobilization is an important prophylactic measure against suppurative arthritis. The indicated emergency surgery for wounds of joints is the same for wounds seen late and even for those with established suppurative arthritis as it is for wounds seen early. Open drainage incisions are seldom, if ever,

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indicated as the treatment for wounds of joints or for suppurative arthritis. Such a process can be eliminated more effectively by thorough intra-articular cleansing followed by closure of the joint, instillation of penicillin supplemented by systemic antibiotic therapy and immobilization. DISLOCATIONS

Dislocations of major joints are true surgical emergencies. Reduction of many fractures may be carried out several days after injury with no prejudice to the end result. The longer a dislocation remains unreduced, however, the greater the incidence of complications. Prolonged stretch on adjacent major nerve trunks or blood vessels may cause temporary or even permanent paralysis or ischemia and possible gangrene. Moreover, an open reduction may be necessary, and the end results thereafter often are not optimal. Even if a delayed closed reduction is possible, posttraumatic inflammatory processes about the joint, made worse by the delay in reduction, are likely to limit the return of function. For all these and other comparable reasons, dislocations of major joints deserve prompt reduction. Several techniques of reduction of each of the major dislocations have been standardized for many years. It would be repetitious to outline them here. On the other hand, several features of dislocations of the hip and knee joints are worthy of further discussion. Dislocations of the Hip

This injury occurs most commonly when a front-seat occupant of an automobile in a collision is thrown forward so that a knee strikes the dashboard. The force of the impact travels up the femur and forces the head out of the acetabulum posteriorly. Frequently the posterior wall of the acetabulum is fractured and driven ahead of the femoral head. This combined injury sustained in an automobile collision is often called a "dashboard dislocation." When the physician is confronted with a dashboard injury, the possibility of a dislocated hip must be considered. Often "the diagnosis is overlooked (Fig. 451). The patient may be unconscious, a fact which tends to minimize examination. An associated open fracture of the patella is so evident that an injury in the region of the hip goes unsuspected. Even without these masking injuries a dislocated hip may be overlooked because it is incomplete (as often occurs with a fracture of the posterior acetabular wall). Appreciation of this mechanism of injury as a cause of dislocated hip will tend to minimize errors in diagnosis. Early reduction of a dislocated hip is indicated because, in addition to the reasons outlined above, the incidence of late avascular necrosis of

Emergency Management of Major Injuries of the Extremities 1273 A

B Fig. 451. A, Bilateral dislocation of the hips with fractures of each posterior acetabulum sustained as a dashboard injury. These dislocations were overlooked on poor films made in a small hospital even though the mechanism of injury was typical and the patient would not permit extension of the thighs at the hips and held the thighs internally rotated. B, Postreduction film.

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the femoral head varies directly with the length of time between injury and reduction of the dislocation. As a rule, general or spinal anesthesia is required. When a large, posterior acetabular fragment has been broken away, the dislocated head can sometimes be pulled back into the joint through the defect without anesthesia, but, in general, attempts to avoid anesthesia are not without danger. Important points in the technique of reduction of a dislocated hip are the position of the patient, the position assumed by the surgeon, and the direction in which traction, the fundamental maneuver of reduction, is made on the extremity. It is wrong to place the patient on the fracture table and apply traction in the long axis of the body as is done in closed reduction of fractures of the hip. In reducing these injuries, traction is applied to the thigh with both the hip and the knee flexed to 90 degrees, not in extension. Traction with the hip flexed tends to pull the head back through the rent in the capsule in the opposite direction from that in which it escaped. Traction is usually made with a grasp on the flexed leg just below the knee. Strong countertraction is provided by an assistant holding down the pelvis. Mild rotation of the thigh outward as traction is made is often advantageous. Reduction is demonstrated when the thigh easily drops into complete extension and external rotation at the hip. Reduction is facilitated by positioning the patient so that the surgeon may stand with his legs straddling the patient's pelvis. The patient may be placed on a pad on the floor, but this is awkward for the anesthetist. The near-ideal arrangement is to place the patient on an x-ray table which is sufficiently wide to afford room for the surgeon to stand on it. With this position for reduction, x-ray confirmation of clinical reduction is easily obtained. In those dislocations of the hip complicated by a fracture of the posterior acetabular wall, reduction of the dislocation often causes the fragments of acetabulum to fall into a good position. The significant factor in these injuries, however, is the size of the fragments. Small fragments may be ignored whether they fall into good position or remain· unreduced. On the other hand, when the fragment or fragments are large, even though they do fall into a good position, subsequent displacement and spontaneous redislocation of the hip can easily occur through the defect in the acetabular wall. Large acetabular fragments, reduced or unreduced, therefore demand open reduction and internal fixation in order to provide a stable, posterior acetabular wall. The pitfall in these injuries is underestimation of the size of the fragments and thereby underestimation of the defect created in the posterior acetabulum. At operation the fragments and the acetabular defect are always much larger than they appeared on roentgenogram. If any doubt

Emergency Management of Major Injuries of the Extremities 1275 exists about the need for open reduction, the operation is probably indicated. Open reduction is performed through a posterior incision across the buttock parallel with the fibers of the gluteus maximus muscle, which is split. The short hip rotators are severed near this insertion and folded backward, thereby protecting the sciatic nerve. When this is done, the posterior portion of the capsule of the hip (usually torn) comes into view. Further dissection permits the fragments of acetabulum to be visualized, freed, replaced and secured, usually by several screws. The hip joint is cleaned of old blood clot and particles of crushed bone and cartilage before replacement of the acetabular fragments. Occasionally a fragment of the head of the femur is sheared off as it leaves the acetabulum, which usually remains intact. This fragment may block reduction of the dislocation, particularly if it falls into the acetabulum. Under these circumstances operative excision of the fragment is necessary in order to permit reduction of the dislocation. On the other hand, if reduction of the dislocation is achieved, the fragment of femoral head may usually be ignored, since it is unlikely to interfere with subsequent function of the hip. Early surgical excision is contraindicated for two reasons: the operation itself may further damage arterial flow to the femoral head from capsular arteries and increase the chances of avascular necrosis, and, in addition, the operative trauma may predispose to myositis ossificans about the joint. Dislocation of the Knee

True dislocation of the knee is a relatively rare injury produced by direct violence to the proximal end of the tibia or distal end of the femur while the knee is extended or by forced hyperextension of the leg at the knee. For this dislocation to occur, both collateral and both cruciate ligaments must be torn. Probably a momentary incomplete dislocation with spontaneous reduction occurs occasionally. In these instances, although a dislocation of the knee is not present when the patient is examined, there is marked instability in all directions. Closed reduction of a complete dislocation of the knee is usually obtained easily by traction and manipulation. An immediate operative repair of the torn collateral and perhaps the cruciate ligaments will predispose to the optimal end result in the shortest period of time even though many excellent knees have been obtained after closed reduction and immobilization in a plaster cast for two or three months. Torn Collateral LigalIlents of the Knee

A tear of either collateral ligament of the knee produces in effect an incomplete dislocation and is worthy of consideration among the major injuries to the extremities. The indicated treatment varies with the extent

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of the tear, which is determined by the amount of abnormal lateral mobility. Instability may be masked by the splinting effect of the musculature of the thigh, particularly during the pain of examination. Examination under anesthesia, therefore, may be necessary to demonstrate the full extent of the tear in the collateral ligament. When the extended leg can be abnormally abducted (after injuries to the inner side of the joint, for example) only 10 to 15 degrees or less, the injury is probably essentially a stretching tear rather than a true rupture of the ligament, and only immobilization in a plaster cylinder cast for four to six weeks is indicated. On the other hand, when the degree of lateral instability exceeds 15 degrees, primary operative repair is usually the treatment of choice. This permits a thorough intra-articular inspection. If the adjacent semilunar cartilage is torn, it can be removed. The torn ligament is often found folded on itself, so that, without operation, the integrity of the ligament would not be restored by healing processes. The torn ligament is repaired (or reattached if it is found avulsed at either attachment), usually with strong silk. Immobilization is necessary for only about four weeks, although weight bearing is avoided for another two to four weeks. The accurate surgical repair of the torn collateral ligament predisposes to the optimal functional result for such a severe injury in the minimum period of time. 3720 Washington Boulevard St. Louis 8, Missouri