RU2275877C2 - Method for intraosseous osteosynthesis of oblique and screw-shaped tibial fractures - Google Patents

Abstract

FIELD: medicine, traumatology, orthopedics.

SUBSTANCE: after open reposition of bony fragments one should apply a screw through them being perpendicular against tibial axis from anterior-external side, and a Kirschner's needle - being perpendicular against the fracture line from anterior-internal side of the bone which should be perosseously bent at acute angle towards the screw to be screwed onto it to screw in a screw to provide compression of the fragments.

EFFECT: higher efficiency of intraosseous osteosynthesis.

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Description

The invention relates to medicine, namely to methods of treatment used in traumatology and orthopedics.

The main conditions for treating fractures of the tubular bones in general and osteosynthesis in particular are anatomical reduction and stable fixation of bone fragments while maintaining blood supply to the damaged limb. The results of treatment depend on maintaining the correct ratio between them. Thus, the desire to achieve an ideal reposition of bone fragments and the absolute stability of their fixation is often in conflict with maintaining adequate blood supply to the fracture zone. Skeletalization of bone fragments over a large extent and implantation of massive metal structures in the tissue is accompanied by significant intraoperative trauma, bone ischemia and inhibition of its regenerative properties. Therefore, the main direction of improving osteosynthesis is to maintain a balance of mechanical and biological conditions for the healing of fractures, namely, the combination of atraumatic surgery with a minimum number of metal structures implanted in tissues (Korzh A.A., Belous A.M., Pankov E.Ya, 1972; Tkachenko S .S., Rutsky V.V., Demyanov V.M., 1987; Korzh A.A., 1989, 1992; Tkachenko S.S., Gaidukov V.M., 1990; Kuzmenko V.V., 1990; Kuzmenko V.V., Skoroglyadov A.V., 1995; Tishkov N.V., 1995; Khomutov V.P., Dedushkin V.S., 1995; Ayeni JP, 1988; Engelhardt P, Velasco R, 1994; Bastian L, Blaunth M., 1995 et al.). This is especially important on those segments of the limbs whose blood supply to the bones due to topographic and anatomical features does not have sufficient compensation reserves. These include the shin, the crest, and the anteromedial surface of the tibia which is poor in soft tissues, which are an essential source of bone blood supply. Therefore, it leads in the number of nonunion fractures, the development of pseudoarthrosis and post-traumatic osteomyelitis (Balagurova G.G., 1985; Abduev B.D., Sidorenkova M.A., 1986; Eskin N.A., 1987; Larionov A.A., Smotrova L.A., 1990; Vorfolomeev N.V., 1990; Stetsula V.I., Gunko Yu.G., 1990; Khadjanov I.Yu., 1992; Agadzhanyan V.V., Pronskikh A.A., 1993; Zubikov BC, 1995; Abduev V.B., 1996; Teterin O.G., 1998; Trueta J. 1963, 1974; Trias A., Fery A., 1979; Duweltus PJ, Connolly JF, 1988; Ciuccarelli C. , Cervellati C., 1989; Cibo S, 1992 et al.).

In osteosynthesis of oblique and helical fractures of the tibia, when the fracture line more than doubles the diameter of the bone, often one screw is enough to achieve adequate intraoperative mutual adaptation of bone fragments. However, due to rotational instability and backlash of the latter around the axis of the screw, there remains the danger of their secondary displacement. To prevent this, one has to either pass another screw through the bone fragments or significantly expand the indications for the use of bone osteosynthesis with a plate of 4-6 screws. In the first case, this can lead to cracking of the cortical plate between the two screws (especially with a small fracture line - within 1.5-2 bone diameters), worsening of the fracture and osteosynthesis failure, and in the second, which we chose as a prototype, to skeleton fragments the tibia over a large extent and the compulsion to increase the amount of metal implanted in the tissue.

As a prototype method, we provide bone osteosynthesis with plates, described in the manual on traumatology and orthopedics for doctors, edited by Yu.G. Shaposhnikov (1997). Its essence lies in the fact that after an open reposition of bone fragments, a plate is applied osseously, through the holes of which 4-6 screws are inserted intraosseously perpendicular to the axis of the damaged segment, which hold the plate and bone fragments in a predetermined position (Fig. 1). In this case, the plate must be used taking into account the tensile forces, without which even the most advanced osteosynthesis does not guarantee stability of fixation and timely healing of the fracture. Surgeons often try to compensate for insufficiently stable osteosynthesis using more powerful plates, believing that they are more reliable, however, according to the materials of M. Muller (1971), fractures of wide plates are recorded 20 times more often than narrow ones. On the lower leg, tensile forces, due to the leverage of the fragments and the tendency to widen the fracture gap, act on the anterolateral side. This means that in order for them to transform into compression forces at the junction of fragments of the tibia and contribute, rather than hinder the stability of osteosynthesis and timely healing of the fracture, the plate must be placed on the anterior-inner side of the leg segment. However, the observance of this condition is impeded by the need to cover the metal structure with soft tissues, on the anterolateral side represented only by skin and subcutaneous tissue. Soft tissue deficiency makes the success of bone osteosynthesis with the placement of the plate on the anterolateral side of the lower leg doubtful, because, firstly, the blood supply to the tissues above the plate, already limited due to the lack of muscles, suffers, and secondly, the metal structure, acting subcutaneously , may cause an internal pressure sore (usually along the front edge of the plate and in the projection of the screw caps). This causes tissue ischemia, prolongs wound healing and is fraught with inflammatory complications. Therefore, often the surgeon, unable to cover the plate with soft tissues without tension and anticipating postoperative complications, is forced to place it on the anteroposterior side of the tibia. When establishing a metal structure, soft tissues are recommended to be peeled off from the bone by no more than half its diameter, and the plate should be placed on the periosteum, since peeling of the bone disrupts the blood supply to the cortical layer of bone by half its thickness. Compliance with this condition is not always feasible, because the periosteum itself is intimately soldered to surrounding soft tissues and its separation from the bone is technically simpler than from these tissues. Thus, the bone under the plate, as a rule, to one degree or another suffers from a lack of blood supply, delaying the time of fracture consolidation.

The disadvantages of the prototype method are as follows:

1) Alternative observance of biomechanical and biological conditions of fracture consolidation, as ensuring the optimality of the former (placement of the plate taking into account the tensile forces on the anterolateral side of the lower leg) is in conflict with the latter (the impossibility of covering the metal structure with muscles and fraught with suppuration of tissue ischemia over the plate with the probability of exposure of the latter). Biomechanically unfavorable placement of the metal structure delays the healing time of the fracture and can lead to fatigue fracture of the plate.

2) The need for wide operational access to establish the metal structure and the presence of a large amount of metal (12-16 cm plate with 4-6 screws) in the fracture area is associated with significant intraoperative trauma, ischemia of bone fragments, the likelihood of metallosis (body reaction to metal) and inflammatory complications, which delays the healing time of the fracture and worsens the results of its treatment.

3) The single-plane nature of the holding of screws, which is mechanically irrational and involves the need to increase their number to achieve stability of osteosynthesis.

4) The inevitability of osseous compression under the plate when tightening the screws on it, without which it is impossible to achieve stability of the metal structure and which is accompanied by ischemia of the tibial cortical plate under it. Along with the inhibition of osteogenesis, this is fraught with the danger of cortical osteomyelitis.

5) The need for wide operational access to remove metal after fracture healing (with a cut along the old postoperative scar).

All this makes it appropriate to search for alternative methods for intraosseous osteosynthesis of oblique and helical fractures of the tibia.

A method for intraosseous osteosynthesis of oblique and helical fractures of the tibia is proposed, which consists in the following. After an open reposition of bone fragments perpendicular to the axis of the tibia from the anterior external side, a cortical screw (Fig. 2a) with a diameter of 4.5 mm and a length of at least 3 mm greater than the diameter of the bone (3.5-5 cm) is passed through them. The direction of insertion of the screw from the front outer side was chosen by chance and is due to the need to cover the extra bone part of the metal structure with soft tissues, namely, the screw head protruding above the bone surface. Having screwed the screw all the way and making sure of the mutual adaptation of the bone fragments, the Kirchner needle is held from the front-inner side of the tibia perpendicular to the fracture line until it comes out on the other side of the bone (Fig.2b). This creates the most rational placement of metal structures and provides maximum fixation rigidity with minimal trauma and material consumption. Then the screw is unscrewed by 0.5 cm, and the osseous part of the spoke is bent at an acute angle towards the screw, from which from left to right, taking into account the subsequent tightening of the screw clockwise along its smallest diameter, i.e. along the furrow between two turns of its thread, they also bend with the formation of a loop (pigv). The latter does not have to be closed, but its diameter must be inferior to the diameter of the screw head. The remaining part of the knitting needle is bitten off, and the screw is screwed again until it stops, thus fixing not only bone fragments, but also the loop of the needle pressed between the screw head and the bone surface (Fig. 2d), which excludes the possibility of migration of the spoke. The latter, along with increased stability of the metal structure, plays the role of a stopper, which excludes the probability of secondary rotational displacement of bone fragments around the axis of the screw.

As an example of the application of the proposed method, the following observation. Patient Z., 29 years old, was admitted to the Republican Orthopedic and Traumatology Center (RTC) in Makhachkala on January 15, 01 with a diagnosis of Closed screw-shaped fracture of the lower third of the tibia and upper third of the fibula of the left leg with displacement. She was injured when falling on the street 1.5 hours before admission. A skeletal traction over the calcaneus with a load of 5 kg was applied. On the control radiographs dated January 16, 01, the unsatisfactory position of the bone fragments was noted and indications were given for the operation of intraosseous osteosynthesis. On January 17, 01, under conduction anesthesia, a longitudinal arcuate incision along the anterior surface of the lower third of the lower leg with a length of 8–9 cm with dilution of soft tissues to the sides of the tibia crest revealed a fracture zone. About 300 ml hematoma was evacuated. The soft tissues interposed between the bone fragments are pushed back, and fragments of the tibia are repositioned. The latter was held by a bone holder. Then, perpendicular to the axis of the tibia from the anterior outer side, a channel was drilled and a thread was tapped, a cortical screw with a diameter of 4.5 mm and a length of 38 mm was passed through them, which was 5-7 mm more than the diameter of the bone. Having screwed the screw all the way and making sure that the bone fragments are mutually adapted, the Kirchner spoke was drawn from the front-inner side of the tibia perpendicular to the fracture line until it reached 7-8 mm on the other side of the bone. This created the most rational placement of metal structures and ensured maximum fixation stiffness with minimal trauma and material consumption. Then the screw was unscrewed by 5-6 mm, and the osseous part of the spoke was bent at an acute angle towards the screw, on which from left to right between two turns of its thread it was again bent to form a loop. The diameter of the latter was smaller than the screw head. The rest of the knitting needles were bitten off with pliers, and the screw was screwed again to the stop, fixing, thus, not only bone fragments, but also a knitting needle loop pressed between the screw head and the bone surface. This, along with an increase in the stability of metal structures, excluded the probability of needle migration and rotational displacement of bone fragments around the screw axis. After a manual check of the viability of osteosynthesis, the wound was sutured in layers without tension of the soft tissues and with tubular drainage left for a day. The posterior plaster cast was applied from the upper third of the thigh to the toes of the foot. The postoperative period was uneventful, the sutures were removed on the eighth day after surgery. The patient was discharged for outpatient treatment on January 26, 01. Gypsum immobilization was removed on April 27, 01. After a course of rehabilitation treatment, the function of the left lower limb was fully restored. Metalwork was removed on 08.25.01 g through a 5-cm skin incision along the old postoperative scar. The result of the treatment was regarded by us as good.

The advantages of the proposed method are the following:

1) Non-invasiveness, due to the lack of need for skeletonation of the ends of bone fragments to establish metal structures and the minimum amount of metal implanted in the tissue.

2) Profitability and the most complete compliance with the principles of building mechanics, according to which the minimum amount of material used is combined with the maximum efficiency of its application.

3) Elimination of the probability of needle migration and rotational instability of bone fragments without the need for a bone plate, an increase in the number of screws and the associated probability of cracking and ischemia of bone fragments.

4) The rational location of the metal structure, namely in three planes, when along with the maximum gain in the stability of fixation of bone fragments, the likelihood of conflict between the screw and the spoke is eliminated even with a small fracture length (1.5-2 times the diameter of the bone).

5) Minimizing the likelihood of developing metallosis and inflammatory complications of osteosynthesis.

Thus, the proposed method is atraumatic, simple and economical, and its use can significantly improve the results of the treatment of oblique and helical fractures of the tibia.

Claims (1)

A method for intraosseous osteosynthesis of oblique and helical fractures of the tibia, which consists in the fact that after an open reposition of bone fragments perpendicular to the axis of the tibia from the anterior side, a screw is passed through them, characterized in that a Kirschner needle is drawn perpendicular to the fracture line from the front-inner side of the bone, which bend at an acute angle to the side of the screw, screw the needle from left to right with one turn and screw the screw all the way.

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