CHAPTER XXXIX. FRACTURES OF THE LOADER END OF THE FEMUR. (Part 1)

CHAPTER XXXIX. FRACTURES OF THE LOADER END OF THE FEMUR. Under this heading are included the various fractures occurring in the lower end of the bone, some of which enter the joint cavity of the knee. Separation of the lower femoral epiphysis is also con- sidered under this heading instead of being taken up separately as is customary. Surgical Anatomy. — The lateral surfaces of the large expanded lower extremity of the femur are subcutaneous and can be palpated without difficulty. With the knee flexed the upper margin of the trochlear surface may be felt anteriorly. The two heads of the gastrocnemius are attached posteriorly just above the condyles. To the external surface of the outer condyle (outer tuberosity) is attached the tendon of the popliteus, and at the lower end of the external supracondylar ridge is the origin of the plantaris. In the notch between the condyles are attached the upper ends of the crucial ligaments. The popliteal artery lies in close relation with the posterior surface of the bone, from the point where it crosses the internal supracondylar ridge to the bottom of the intercondyloid notch. It may be injured in this position when fracture of the lower end of the bone occurs. The vessel is more often temporarily compressed than permanently injured, which fact accentuates the importance of early reduction. The popliteal nerve and vein lie more superficially than the artery, and accordingly are much less frequently injured by displaced fragments. The most common fracture of the lower end of the femur is trans- verse and a short distance above the condyles. Occasionally the lower fragment is split vertically, thus producing the typical T- or Y-fracture which enters the joint cavity. A more severe type of T-fracture is one in which the lower end of the shaft is driven into the lower fragment with considerable comminution and a vertical splitting into the intercondyloid notch. If it were not for the inter- condyloid notch the T-fracture would probably not occur. Either condyle may be broken off from the remainder of the bone. 574 FRACTURES OF LOWER END OF FEMUR 575 AVlieu force is applied to the knee in a lateral direction or when violence is transmitted longitudinally through the leg, the tuber- osities of the tibia play an important part in the pressure they may exert against the condyles of the femur. In like manner the pull of the lateral ligaments may result in fracture of a condyle when Fig. 641. Fig. 640. — Lateral view of the lower end of tlie femur. Fig. 641. — Coronal section of the lower end of the femur. the knee is subjected to lateral angular displacement. It is more common for the lateral ligaments to tear away only their bony attachments on the femoral tuberosities. This condition is usually represented by a portion of the surface compact tissue, together with some of the underlying cancellous bone, remaining attached to 576 FRACTURES AND DISLOCATIONS the ligament which is torn away and displaced from the tuberosity. This type of fracture is more properly a complication of subluxa- tions or ' ' sprains ' ' of the knee, and will be considered under ' ' Dis- locations of the Knee," page 613. The epiphyseal cartilage corresponds roughly to a horizontal plane passing just above the condyles and through the adductor tubercle. The top of the trochlear surface just touches this plane. The lower femoral epiphj^sis is ossified from a center which makes Fig. 642. — Rontgenogram of the knee showing the locations of the epiphyseal car- tilages. its appearance shortly after birth. Epiphyseal separations cannot occur after the twentieth year since the epiphysis joins the shaft at this time. In fact they are rare after the sixteenth year. The injuries, then, to which the lower end of the femur is subject are: supracondylar fracture, T-fracture, fracture of either condyle separating it from the remainder of the bone, epiphyseal separa- tion and avulsion of a portion of the surface of a tuberosity by the pull of the ligaments. In rare instances we may see a longitudinal splitting of the lower end of the shaft which extends through the FRACTURES OF LOWER END OF FEMUR 577 Fig. 644. Fig. 643. — Fracture of the lower end of femur with angular deformity and crush- ing of cancellous tissue in the lower fragment. Fig. 644. — Supracondylar fracture Avith pronounced overriding deformity. ig. 645. Fig. 646. Fig. 645. — Old displaced fracture with refracture through callus Fig. 646. — Fracture of femur with lateral overriding deformity. 578 FRACTURES AND DISLOCATIONS lower end of the bone into tlie joint cavity. In some cases we may see a portion of the surface of the tuberosity driven inward by severe violence confined to a small area. Symptoms. — The symptoms vary with the age of the patient and the severity and nature of the injury. In supracondylar fracture, fracture of one of the condyles or epiphyseal separation, the loss of function is complete. The patient is unable to stand on the injured member or to raise the foot from the bed. Deformity is usually present and varies with the position of the fracture. In the simple supracondylar type the lower fragment may be displaced in any Fig. 647. — Fracture of the lower third of the femoral shaft. Note the shortening, external rotation and thickening of the thigh. Lower fragment displaced posteriorly. Case first seen twent>-foar hours after injury at which time this photograph was taken. Fig. 648. — Compound comminuted fracture of the lower end of the femur. The lower end of the upper fragment is displaced anterioi"ly and has penetrated the skin. The resulting wound shows black in the photograph and blood is seen trickling down the side of the knee. direction. If it is free to move (if not obstructed by the lower end of the upper fragment) the action of the gastrocnemius will tend to displace it backward. In any type of fracture of the lower end of the femur it is more common to see the lower end of the upper fragment displaced forward and downward- while -the lower frag- ment is displaced backward. In epiphyseal separations the reverse is usually true, the epiphysis is displaced forward and upward, in front of the lower end of the diaphysis. In T-fracture or fracture FRACTURES OF LOWER END OF FEMUR 579 of one of the condyles the transverse diameter of the lower end of the femur is usually increased. Injury to the popliteal artery may occur in any of these fractures of the lower end of the femur, especially in epiphyseal separations, and the resulting symptoms of disturbed or destroyed circulation will depend on whether or not the artery has been compressed or lacerated. In fractures of the lower end of the femur it is not uncommon to see the lower end of the upper fragment projecting" through the skin above the patella. In epiphyseal separations the condition is often rendered compound by the lower end of the diaphysis projecting through the skin cov- ering the popliteal space. Abnormal mobility is regularly present but the proximity of the knee joint renders this symptom at times difficult to recognize. In fracture of one of the condyles or in T-fracture the loss of lateral stability in the knee is usually pronounced. Crepitus may be elicited unless the fragments have overridden so that their serrated surfaces are no longer in contact. In epiphyseal separations the epiphj^sis is, as a rule, displaced anteriorly and upward and crepitus cannot be elicited until the fractured surfaces are brought back into contact and even then it is soft and cartilaginous rather than bony. Diagnosis. — If the case is seen early before the onset of swelling, it will usually not be difficult to recognize the nature of the injury. There is, as a rule, disturbance in the alignment of the bones of the thigh and leg which can be determined by inspection. Short- ening of the thigh is the rule since the fragments so frequently override. Fracture in this region without deformity is the excep- tion. Abnormal mobility is usually characteristic. The lateral stability of the knee is impaired, especially when the lower fragment is divided into two or more pieces. Where the swelling is great it may be difficult to determine whether the fracture is in the lower end of the femur or the upper end of the tibia. The deformity in these fractures is variable, though the most common displacement is backward in the lower fragment. In epiphyseal separations the deformity is more uniform wdth the' epiphysis displaced upward and forward. This condition is most commonly seen about the tenth or twelfth year and the crepitus elicited is soft and cartilaginous rather than bony. All unnecessary manipulation for diagnostic purposes should be avoided because of the liability of injury to vessels and nerves. 580 FRACTURES AND DISLOCATIONS The manipulations incident to reduction will afford as much information to the surgeon as those conducted simply to establish a diagnosis. When the X-ray is available the most complete informa- tion concerning the fracture may be gained without disturbing the parts. Treatment. — Anesthesia is essential in reducing fractures of the lower end of the femur. AYith a simi)le supracondylar fracture reduction should be accomplished as soon as possible and the frag- ments immobilized in splints. Difficulty is sometimes experienced in bringing the fractured surfaces back into apposition and w^hen such is the case we should resort to operative intervention. The A Fig. 649. — Cabot posterior Avire, hip splint Wire bent to make splint. B. Side view showing bends to conform to the posterior surface of the lower extremity and ^ _ aiorm to lue posierior suriace oi me lower exire hips, with knee in a position of slight flexion. C, Splint covered and lateral tached to encircle the trunk. -^ 650. — Cabot posterior wire splint bent to be used as double inclined plane. fact that the popliteal artery may be injured during reduction should never be lost sight of and accordingly manipulations should be most guarded. If reduction cannot be accomplished by traction and manipulation, the open method should be instituted at once, especially if there is the slightest indication that the popliteal artery is being compressed. In manipulating the fragments pressure should never be made in the popliteal space lest the artery be driven FRACTURES OF LOWER END OF FEMUR 581 against the end of one of the fragments. Pressure to force the lower end of the upper fragment forward should be made in the middle of the thigh posteriorly, where there will be no danger of injury to important soft tissues. In the presence of a T-fracture or a frac- ture of one of the condyles, an attempt should be made to force the Fig. 651. — Du]>in's adjiistable splint used as a doulde iiudinod jdane in a case of fracture of the femur. Extension in the long axis of the femur is employed to maintain reduction. Fig. 652. — Dupuy's adjustable metal splint for the treatment of fractures of the lower extremity. condyles together as reduction is being accomplished. This is an important matter since separation of the femoral condyles means loss of proper alignment between the femoral and tibial articular surfaces with subsequent disturbance in the function of the knee joint. If the fracture is near the knee and the lower end of the upper fragment is displaced forward the prominence thus produced 582 FRACTURES AND DISLOCATIONS may interfere with the action of the patella and quadriceps after union has taken place. In separation of the epiphj^sis reduction should be accomplished at once and with the least possible manipulation. Gradual flexion Fig. 653. — Adjustable doulole inclined plane, fracture box. of the knee while pressure is being exerted on f he epiphysis will aid materially in effecting reduction. If reduction cannot be ef- fected by traction, counter-traction, flexion and direct pressure on the epiphysis, it should be accomplished by operative intervention. Fig. 654. — Hogden's splint. This splint may be used as a double inclined plane. The manner in which the ropes are arranged affords traction as well as suspension. Repeated attempts at reduction of an epiphysis, with intervals of delay, are absolutely to be condemned. The sequel of such surgery is amputation. If the first attempt is unsuccessful, operation should be performed at once. Operative Treatment. — Operation is indicated when good reduc- tion cannot otherwise be accomplished. An incision along the inner border of the cpiadriceps extensor will expose the fragments, and manipulation of the lower extremity may be aided by direct trac- tion on the displaced fragments, by means of bone hooks or forceps. Increasing the angular deformity may render reduction easy which would otherwise have been difficult. After the serrated surfaces FRACTURES OF LOWER END OF FEMUR 583 have been engaged the angular deformity is corrected and the frag- ments brought back into good alignment. If the fracture is of the T-type it is often advisable to make two longitudinal incisions, one on the inner and the other on the outer aspect of the thigh opposite the lower end of the bone. With the parts thus exposed the condyles are forced together and back into position so that they properly fit the articular surfaces of the tibia. If a tendency tow^ard recur- rence of deformity is noted they should be secured in proper rela- tion with each other by some means of internal fixation. If two holes are drilled transversely through the lower end of the bone above the cond3^1es, a w^ire may be passed through the bone from one side to the other and back again, thus holding the fragments together. A Lane plate may be used on the anterior surface of the bone if the displacing strain is not too great. It should be remem- bered that the lower end of the femur is covered by a very thin layer of compact tissue w^iile the interior of the bone is composed of a cancellous structure wiiich offers an exceedingly poor foothold for screws, nails or pegs. The most secure fixation, therefore, is the transverse wiring just described. If transverse wiring is employed below the upper border of the trochlea care should be exercised to avoid drilling into the supracondyloid notch. The drill holes should, therefore, be placed well forward. (See ''Anatomy of Low^er End of Femur," page 574. The knee-joint should not be opened unless it is found that proper fixation cannot otherwise be obtained. With reduction and fixation of the fragments accomplished the wound or wounds are closed and the lower extremity immobilized in whatever position shows the least tendency toward recurrence of deformity, as demon- strated during operation. Extension, semiflexion or flexion may be employed. As a rule, however, it will be found practicable to immobilize the lower extremity on a ham splint in a position just short of complete extension. When the fracture is treated in this position a Buck's extension following operation is usually indi- cated to relieve the muscular spasm, steady the member and re- lieve the pressure between the articular surfaces of the tibia and femur. Padding of the splint for the purpose of exerting pres- sure in the popliteal space to effect or maintain reduction is not permissible. Tenotomy of the tendo Achillis to overcome backward displacement of the lower fragment has been advised and prac- 584 FRACTURES AND DISLOCATIONS tised but is probably an unwise measure. It is often unsuccessful and by no means as satisfactorj^ as open treatment with direct fixation of the fragments. There is usually little tendency toward recurrence of deformity following reduction of an epiphyseal separation, if the lower ex- tremity is treated in the semiflexed position. Should the excep- tion, however, be encountered and internal fixation prove necessary, absorbable suture material is the only material which should be used in holding the epiphysis in place. Loops of wire or a Lane plate should not be used across an epiphyseal cartilage. A light plaster cast extending from the groin to the ankle with the knee in semi-flexion will usually be found quite satisfactory in im- mobilizing the parts. It should not, however, be employed until after the traumatic reaction has subsided. If the cast is cut open before the plaster has dried it may be applied immediately fol- lowing the operation. After-Treatment. — Considerable traumatic reaction usually fol- lows the accident, and during the first week repeated adjustments will be necessary in making allowances for the onset and subsidence of swelling. Traumatic arthritis of the knee is the rule, especially in epiphyseal separations and fractures entering the joint cavity. The knee should be snugly bandaged and an ice cap should be kept in position most of the time during the first week. A long side splint such as used in fractures of the shaft of the bone, adds greatly to the security of immobilization when the fracture is treated in the extended position. If the lower fragment shows a tendency to posterior displacement not controlled by straight Buck's extension, a double incline plane should be employed or the lower extremity put up in a cast in a flexed or semi-flexed position. At the end of six or eight weeks the dressings should be removed and passive motion begun. In another week or ten days the pa- tient may be allowed out of bed and may begin the use of the member cautiously. He may bear a little weight on it while get- ting about with the aid of crutches and a moderately high sole on the opposite foot. In children union is much more rapid while in the aged it may be very much delayed. The usual treatment of epiphyseal separations is with the knee in a position of semiflexion. At the end of three or four weeks the knee may be carefully brought to the extended position and FRACTURES OF LOWER END OF FEMUR 585 massage beguu. Guarded passive motion