PART IV. SPECIAL SUBJECTS. (Part 4)

is driven into the extremity of one of the long bones it 762 FRACTURES AND DISLOCATIONS will usually be found possible to tear it out Avith the fingers ; but if the shaft is selected as the site of the experiment the nail will be found as solidly seated as if driven into wood. This difference is entirely dependent upon the disposition of the compact tissue, and it is evident, therefore, that before a surgeon operates on a given region he should be acquainted with the internal structure as well as the surface form of the portion of the bone fractured. If a nail or screw once ogives in cancellous tissue the securitv of fixa- Fig. 830. — Gerster's turn-buckles for reducing difficult fractures, especially of the long, large bones such as the femur and humerus. They may be used to advantage in some cases though it is seldom that proper angulation of the fragments and manipulation fail in accomplishing reduction in the open method. Great force can be exerted by this mechanism and it should not be used without due regard for the damage it may inflict. tion is lost, but on the other hand a loop of wire never releases the fragments until entirely torn out even though some displacement may occur. Screws, like nails, depend on the compact tissue for their hold, and it is apparent that their value decreases as the epiphyses are approached. The thread of any screw used in bone work should continue to the head and the screw itself should be of the type used in woodwork. Sherman has devised a screw of the machine type with a shaft of uniform thickness throughout. The end of the screw is made like a tap so that it cuts its own thread as THE OPEN TREATMENT OF FRACTURES 763 it sinks into the bone. The principle is good and the screw should be efficient, though the author has had no experience with it. "When a screw is driven home it should not be too tightly fixed lest it strip the threads cut in the bone or cause the subsequent absorp- tion of compact tissue through too great stress. Ivory pegs are practically unused at the present time. Nails and screws should be made of steel and either nickel or silver plated. Fig. 831. — Appliance for holding plate in position while screws are being placed, ilso holds fracture in reduction. The Four-post Clamp. — Numerous modifications of the four-post clamp have been devised and used with more or less success though they have been almost entirely superseded, in the last few years, by the Lane plate. Notable among the variations of the four-post clamp is the one devised by Parkhill in which the fragments are held in alignment by four long, threaded, steel rods. These rods are screwed into drill holes, two on either side of the fracture, and held together at their superficial ends by a special locking device (see Figs. 832 and 833). The four posts must be in the same plane and parallel to each other in order that this particular locking device may securely hold them ; it will readily be seen that this type of appliance is difficult of application. Some other modifications of the four-post clamp do not require that all the posts should be parallel, although it is necessary in all types that they be in the same plane. Excellent results have been secured by using the four-post clamp, and it will be found at the 764 FRACTURES AND DISLOCATIONS present time the most satisfactory method, next to the Lane plate, of securing some forms of fracture. If the mechanics of the clamp be studied, and compared with the plate, its inferiority will be apparent. In tracing the fixation through the clamp from one fragment to the other it will be seen that there are twice as many points of possible motion as compared with the plate. Thus a four- Fig. 832. — Shows a compound fracture of tibia and fibula. Xote how the upper end of both lower fragments project through the skin. The angle at which the leg is held shows the flail-like condition. Picture taken a few hours following injury. Case seen with Drs. Lyman and Thompson. Fig. 833. — Same case as shown in Fig. 832 after reduction and securing of the frag- ments by means of Freeman's modification of the four-post clamp. post clamp has eight points of possible motion, whereas a four-screw plate has only four. In addition to this the four-post clamp is at a disadvantage because of the distance of the locking device from the bone, which means so much leverage against fixation. Besides the mechanical inferiority of the four-post clamp, it will be ob- served that four tracts must be left open from the bone to the skin when the posts are in position, which can only mean increased risk THE OPEN TREATMENT OF FRACTURES 765 of infection during the after-treatment. It has been claimed by some that the four-post clamp possesses a distinct advantage in that no foreign body is ultimately left within the tissues. This argument may seem sound theoretically, but practice has proven i^^ Fig. 834. — Set of Sherman's modification of Lane's Pierce & Co. of Philadelphia. Made of Vanadium steel. e manufactured by Harvey beyond a doubt that certain foreign materials properly placed within the tissues are tolerated without the slightest disturbances. In the presence of infection all appliances are alike failures, whether four-post clamp, plate, nail, screw or wire. It will readily be seen, therefore, that the difficulty of application, mechanical in- '66 FRACTURES AXD DISLOCATIONS feriority and increased risk of* infection render the four-post clamp a much more imperfect appliance than is the Lane plate. The Lane Plate. — Lane's method of internal fixation of the frag- ments is accomplished by means of cold-rolled steel plates and screws as shown in Fig. 83-i. The most rigid asepsis is ohserved Fig. 835. — Comparison of the wood screw ordinarily used with, the Lane plate, and Sherman's "tap-screw." (After Sherman in Surg., Gynecol. & Ohstet.) Screwdriver; special construction to fit tap screws. Center point fixes screw and insures vertical and direct driving. 3/e IN, Vanadium steel self-tapping (fluted) screws. Three flutes are provided at end of each screw, thus combining a tap and saew. Fig. 836. — (After Sherman in Surg., Gynecol, d- Ohstet.) during the entire procedure. As soon as the incision is made, the skill edges are protected and other precautions taken to prevent infection as previously described on page 756. The incision is carried down to the bone and the fragments exposed, brought back into alignment and held in apposition by means of a heavy clamp of special design, A plate of appropriate size is then placed and THE OPEN TREATMENT OF FRACTURES 767 held against the bone by the clamp. Holes, slightl}" smaller than the screws to be used, are drilled in the bone corresponding in position to the openings m the plate. Screws are then driven L Fig. 837. — Examples of broken Lane plates of the ordinary type. Note the point at which the break usually takes place. (After Sherman in Surg., Gynecol. t£- Obstet., June, 1912.) Fig. 838 «?.9. Fig. 840. Fig. 841. Fig. 838. — A. P. view of fracture of both bones of leg. Fig. 839. — Lateral view of same case. Pig. 840. — Same case two years later. Fig. 841. — Another view of same case at time Fig. 840 was taken. home, securing the plate to the bone which in turn immobilizes the fragments. The deep structures are then approximated b}^ catgut and the skin incision is closed. Drainage by means of silkworm- 768 FRACTURES AND DISLOCATIONS gut should be established for the first twenty-four or forty-eight hours to allow the escape of fluids which may collect within the wound. The plate should be accurately shaped to the surface of the bone before being screwed into position. It should be so bent as to come in contact with the bone throughout its entire extent without special stress at any given point. If the plate has been securely fixed and the proper aseptic precautions observed through- out the operation, it will remain in position indefinitely without giving rise to trouble. In the extremities of the long bones the plate is not as efficient because of the thinness of the compact tissue on which the screws depend for their holds. A simple wire loop, properly placed, will often hold the fractured extremity of one of the long bones in position more securely than the plate. The Lane plate should never cross an epiphyseal cartilage because of the possibility of disturbing the subsequent growth of the bone. A screw should never be placed closer than one-fourth of an inch from the end of a fragment ; the nearer the screws are placed to the line of fracture the greater the danger of splitting the bone. Plates of various sizes, shapes and weights have been designed by Lane to meet the requirements in different portions of the skeleton and may be secured from the instrument dealer. Absorbable Suture Material is employed and strongly advocated by some surgeons for certain fractures in which the displacing strain is not pronounced. Excellent results have followed its use in many cases, in other instances, however, the nature of the material has been responsible for a repetition of the operation because of the recurrence of deformity. The nature of the fixation required is so different from that to be fulfilled in the approxima- tion of soft tissues that one should not employ absorbable material lightly and without due consideration for its shortcomings as well as its one advantage of being absorbable. It should be remembered that the most important time for fixation does not commence until eight or ten days after the operation when the bony callus begins to form. It is just about this time that absorbable material is beginning to lose its strength, and if it releases its hold within the first two or three weeks another operation may be necessary. The edges of the drill holes may cut the suture material before the callus is sufficiently strong to hold the fragments in position. The so-called ''ten day" and "twenty day" chromicized catgut does not always correspond to the label, in the time which it takes THE OPEN TREATMENT OF FRACTURES 769 for the material to be removed by absorption. Ten to twenty days is more than ample for the processes of healing in soft tissues under aseptic conditions. Bone, however, requires a longer period in which to unite. If the suture material becomes soft and lax Fig. 842. — Tibia from which Lane phitt Non-union present in spite of heavy callus bone where the screws were placed. lias been removed because of infection, seen in plate. Note the absorption of within a week or two, motion may occur between the fragments and delayed or non-union may follow. The surgeon, in the meantime, is laboring under the false impression that the fragments were securely and permanently fixed at the time of operation. In addi- 770 FRACTURES AND DISLOCATIONS tion it might be stated that chromic gut is not as easy of steriliza- tion as are metallic substances, such as wire, and the Lane plate. Absorbable suture material is more commonly used in repair of the patella and olecranon than in other regions. The purpose is accom- plished in either of these two parts hy suturing the torn fasciae attached to the fragments rather than by direct suture of the bone. In conclusion it might be stated that absorbable suture has the advantage of being entirely removed after it has accomplished its purpose, but it is so insecure that it had better be discarded, in most cases, in favor of some metallic, mechanical material. The subject of the open treatment of fractures cannot be con- sidered complete without entering into the uses and indications of bone transplantation. It is not improbable that many of the estab- lished methods in operating on fractures will, in the near future, be revised or even discarded when the possibilities and uses of bone grafting become better known and further developed. Bone transplantation will be taken up in the following chapter. CHAPTER LX. BONE TRANSPLANTATION. One of the most important developments of surgerj^ in recent years is the transplantation of bone to fill in deficiencies in the skeleton which have resulted from injury or disease. As a sur- gical procedure it has become well established in spite of the fact that the fundamental underlying principles are as yet by no means established. The three theories which have had the greatest fol- lowing are those of Axhausen, Macewen and Murphy, and the very diversity of these theories points unmistakably to the fact that the subject has yet to be explored and the actual facts determined. Axhausen maintains that the bone composing the graft invariably dies, and is absorbed and replaced by new bone formed from the periosteum surrounding the transplant. According to this theory the periosteum is all that remains of the original transplant, and the success of the operation depends entirely on this membrane. Macewen of Glasgow is of the opinion that the graft is repro- duced entirely from the osteoblasts within the transplant, and that the periosteum has nothing to do with regeneration of bone, but acts only as a limiting membrane preventing the osteoblasts from penetrating the surrounding tissue. Murphy of Chicago states that the graft acts only as a scaffold- ing for the production of new bone by the osteogenetic elements which pass from the living bone into the transplant at the points of contact. In other words, he maintains that the graft is not osteogenetic but only osteoconductive, and that therefore the solid contacting of the graft with living bone is the important point, and not the activity of the periosteum. It is probable that each of these theories contains some truth but that no one of them is entirely correct. Since the setting forth of these theories much experimental work has been done on the subject, and although much valuable, practical information has been gained in this way yet the ultimate fate of the graft has not been conclusively de- termined. From a practical standpoint we are not so much in- 771 772 FRACTURES AND DISLOCATIONS terested in the theories as we are in knowing the conditions under which bone may be successfully transplanted to fill in defects in the skeleton. Moreover it is not sufficient to know that under cer- tain conditions the operation may be successfully performed but we must know^ just which methods will give the highest percentage of success, and just what conditions are most likely to interfere with the "taking" of the graft. In order that we may develop the practical side of the subject we must examine into the results obtained in some of the more recent experimental work and consider these facts together with the theories just referred to and what we know of the embryonic development of bone and the repair of fractures. Following frac- ture certain tissues, as far as w^e can determine, resume their em- bryonic function and produce bone to repair the lesion. In the embryo the bone-forming tissues seem to be the periosteum and the osteoblast, but whether or not the bone-forming properties of the periosteum are inherent to this membrane or are dependent on the osteoblast cannot be stated. The bone cell is developed from the osteoblast, and in the presence of fracture it is not improbable that the bone cell reverts to its embryonic role and produces bone provided circulation is not destroyed. It would therefore seem that in the repair of a fracture ossification of the soft callus emanates from three sources: namely, the periosteum, the endos- teum, and from the osteoblasts within the bone near the frac- tured surfaces of the fragments. If the bone-forming properties of the periosteum and endosteum depend on the osteoblasts then the process of ossification resolves itself into one word, viz., osteo- blast. A transplant might be considered as an ordinary fragment if it were not for the fact that its circulation has been disturbed by being removed from its original position. This is a most im- portant matter since the life of the bone cell, and hence of the bone itself, depends on an adequate circulation. It is an established fact that if a section of periosteum be stripped up from the bone and transplanted into other tissue (muscle for example), it is capable of living and producing bone. Now a normal bone receives its circulation from three sources : the periosteum, endosteum and the direct ramifications of the nutrient vessel or vessels. In remov- ing a graft the branches of the nutrient artery are of course put out of function, but if the periosteum, when transplanted, can continue to live and reestablish its circulation, it is capable, to a BONE TRANSPLANTATION 773 greater or less extent, of taking care of the attached bone and its contained bone cells. In considering the circulation of the graft and its periosteum it should be remembered that the function of circulation (namely, the supply of oxygen and nutrition and the removal cf waste products) can, to some extent be directly ac- complished by diffusion, osmosis, dialysis and infiltration within the fluids surrounding anci pervading the transplant. A graft stripped of its periosteum may live, when transplanted, but the chances of its doing so are much less than when the membrane is left attached. A periosteum-free transplant is more likely to survive if broken up into small pieces, since the fluids thus obtain freer access to the bone cells. On the other hand it is well known that under favorable circumstances dead bone (sterilized by boil- ing and hence killed) has been successfully grafted into defects in the skeleton and what would