RU2275880C2 - Device for optimizing bone fragment fixation to its bed - Google Patents

Abstract

FIELD: medical engineering.

SUBSTANCE: device has irregularly curved Kirschner wire having loop for wire cerclage and stepwise bends arranged on both sides of the loop with a structure having three longitudinally arranged fragments for making bone contact. The loop is placed on the middle fragment in the device center with pipes transversely joining three longitudinally arranged fragments. The pipes are displaced towards the loop for preventing engagement with bone and are bow-shaped to possess springing properties.

EFFECT: enhanced effectiveness of treatment; accelerated treatment course; low treatment costs.

4 dwg

Description

The treatment of comminuted fractures of the femur remains one of the urgent problems of traumatology and orthopedics. This is due, firstly, to a tendency to increase high-energy damage in the general structure of injuries in recent years; secondly, the predominant exposure to the most socially active contingent of the population and, thirdly, the high incidence of complications (Shaposhnikov Yu.G., 1988; Gryaznukhin E.G., 1989; Belousov V.D., Chobanu A.A., Chobanu F.I., 1990; Bradu, Yu.I., 1990; Kornilov N.V., Glybin V.N., Schepkina E.A., 1994; Zhuravlev S.M., Novikov P.E., 1996; Krasnov S .A., Dubov V.E., 1997; Duwelius PJ, Connolly JF 1988; Bastian L., Blaunth M., 1995, etc.) (1-3). Thus, in the intramedullary osteosynthesis of comminuted fractures of the femur, the stable fixation of a fragment to its bed is of great importance, which is an important and often determining condition for the joint of the fracture (Korzh A.A., 1989, 1992; Kuzmenko V.V. 1990; Tkachenko S .S., Gaidukov V.M., 1990; Belyi V.Ya., Shipunov G.P., 1999; Small JO, Mollan RA, 1992; Brown C., Henderson S., 1996, etc.).

Typically, a bone fragment is repaired and fixed with wire or catgut cerclage. When using catgut for cerclage, its tension may subsequently be lost due to colloidal swelling in a humid environment. The consequence of this is the loss of adequate adaptation of the fragment to its bed until the complete loss of contact with it. In addition, even when using a large diameter chrome-plated catgut, the fracture consolidation process may not fit in the chronological framework for resorption of this suture material.

As a prototype device, we took wire cerclage and the method of its application described in the manual on operative orthopedics and traumatology (B. Boychev, B. Conforti, K. Chokanov, 1962 (4)) and which consists in the following. A bone fragment is laid on its bed and after intramedullary osteosynthesis of the main fragments of the femur, around the diaphysis of the latter, a wire is drawn, the ends of which are twisted together. By circular tension of the wire, the splinter is tightly pressed to its bed (Fig. 1). The disadvantages of the prototype are the following:

1) The possibility of the cerclage loop getting into the gap between the main bone fragments (usually on the other side of the fragment along the perimeter of the bone circumference), which leads to an expansion of the fracture gap, instability of osteosynthesis and inhibition of reparative osteogenesis.

2) The twisting of the wire necessary for the tight adaptation of the bone fragment to its bed and to prevent the cerclage from slipping to one of both sides is accompanied by strangulation of the blood vessels of the bone (“loop strangles the bone”) up to the development of cortical necrosis of the entire circumference. Bone ischemia under the wire loop delays the duration of the course of reparative osteogenesis and is fraught with the danger of developing postoperative osteomyelitis. In addition, the stability of fixing the fragment to the bed, as a rule, is lost due to atrophy and bone resorption under cerclage.

3) The probability of cerclage wire slipping to one of both sides with a secondary displacement and loss of contact of the bone fragment with its bed. The probability of this is the higher, the greater the bone resorption at its border with the metal.

4) The need for additional surgery after 2.5-3 months to remove cerclage in order to prevent bone atrophy under it.

In order to increase the effectiveness of the treatment of comminuted hip fractures by retrograde intramedullary osteosynthesis, we have proposed a device consisting of a figured curved Kirschner needle. To manufacture the device, a Kirschner needle is taken with a diameter of 1-1.5 mm and with the help of pliers bend it with the formation of a loop, the diameter of which varies from 2 to 5 mm. Departing from this loop in both directions by 2-3 cm, perform stepwise bending of the knitting needle with the formation of a figured structure with three longitudinally parallel and 4-6 cm long fragments located in the same plane (Fig. 2). Moreover, the joints of the middle fragment of the structure with both peripheral fragments are formed not in the plane of the latter, but shifted by 2-5 mm in the direction of the loop formed on the middle fragment. This circumstance is essential and is dictated by the necessity of contacting the bone-mounted device with the underlying bone only by its longitudinally parallel three fragments, rather than connecting them transverse to each other by the elbows of the structure. In addition to multi-plane stepped bends (figure 2), the device additionally form an arcuate bend of all three of its longitudinal fragments with a curvature of 10-30 degrees (figure 3). The purpose of this bend is to have the device spring during its use due to its elasticity due to the minimal "shape memory" of the Kirschner spoke metal. The springiness of the device when tightening the wire cerclage on it ensures the constancy of its tight contact (and, therefore, stability of fixation) with the bone - regardless of the resorption of bone tissue at its border with the metal.

The device is used as follows (Fig. 4, a, b). After intramedullary osteosynthesis of the main fragments of the femur and reposition of the bone fragment for the bone length, a wire for cerclage is carried out. One of the two ends of the wire is inserted into the loop of the device. The last along the wire, as if through a conductor, is led over the length of the bone and placed on the bone. Usually it takes about 1/3 of the perimeter of the bone diaphysis (Fig. 4, b), and if you need to increase the circumference of the osseous contact of the device, it can be slightly stretched (extended) in width. In this case, the arrangement of three longitudinal fragments of the device from parallel becomes Z-shaped. Then they perform a “twist” of the ends of the wire with a tight adaptation of the bone fragment to their bed. The node "twist" is usually located outside the abdominal device (Fig.4, a, b).

As an example of the application of the proposed device, the following observation.

Patient G., 34 years old, was admitted to the Republican Orthopedic and Traumatology Center (RTC) of Makhachkala on September 8, 02 with a diagnosis of Concomitant injury: concussion; fracture of V-VI ribs on the right; closed comminuted fracture of the middle third of the left thigh with displacement of fragments; traumatic shock of the I-II degree. The circumstances of the injury: while driving, got into an accident 20 minutes before admission.

A skeletal traction for the condyles of the thigh with a load of 8 kg was applied, and to stabilize the general condition, correct the shifts of the homeostasis of the body and stop the phenomena of concussion and thoracic trauma, on September 17, 02, a retrograde intramedullary osteosynthesis of the left thigh was performed with bone fixation of bone fragment from bone fragment and the proposed device from Kirschner knitting needle. Under endotracheal anesthesia in the patient’s position on the right side, a linear longitudinal incision was made of the skin of the outer surface of the left thigh with a length of 15 cm with sheathing the surgical wound with two Mikulich wipes. The broad fascia of the thigh is longitudinally dissected. In a sharp and dull way along the muscle fibers and through the intermuscular spaces, the hematoma in the fracture area was opened and drained. The ends of the bone fragments are distinguished and economically skeletonized from the lateral side. A sphenoid bone fragment measuring 8 by 4 cm, not separating from the muscle leg associated with it in the area of 2-2.5 cm, is pushed to the side. The fracture planes of the main bone fragments and the fragment were refreshed by removing the remains of the hematoma. Then, with the help of hammer blows, the tetrahedral rod of the CITO was retrogradely inserted into the proximal bone fragment with the exit of its upper part through an additional surgical wound in the region of the greater trochanter of the thigh. After that, the main bone fragments were repaired, and the core was inserted into the distal bone fragment by hammer blows. To fix the bone fragment for the bone length, a wire with a diameter of 0.8 mm was drawn and one of its two ends was brought into the loop of our device. The latter was made in advance from a Kirchner needle with a diameter of 1.5 mm as follows. Using pliers, the needle was bent to form a loop with a diameter of 3 mm. Departing from this loop by 2 cm on both sides, we performed stepwise bends of the knitting needle with the formation of a figured design with three longitudinally parallel fragments located in the same plane. The length of each of them was 4 cm. In this case, the joints of the middle fragment of the structure with both peripheral fragments were made not in the plane of the latter, but shifted by 3 mm in the direction of the loop formed on the middle fragment. In addition to multi-plane stepped bends, a rounded bend of all three of its longitudinal fragments with a curvature of 15-20 degrees was additionally formed on the device. This ensured the springiness of the device during subsequent tightening of the wire cerclage on it in order to maintain its tight contact with the bone, despite the subsequent resorption of bone tissue at its border with the metal. Then they made a “twist” of the ends of the wire with a tight adaptation of the bone fragment to their bed. The spin node is located laterally, i.e. outside the abdominal device. Osteosynthesis is regarded by us as stable. The wound was washed with a solution of novocaine and sutured in layers, leaving tubular drainage for a day. The postoperative period was uneventful. The wounds healed first. X-ray verification of a good comparison of bone fragments. The patient was discharged for outpatient treatment on September 30, 02. Fracture fusion occurred on time. He began to walk without crutches 2.5 months after the operation. The removal of the intramedullary rod and cerclage wire with a osseous device was performed without technical difficulties as planned on 06.25.03. The function was fully restored. The result of treatment is regarded by us as good.

Therefore, the advantages of the proposed device are the following:

1) The presence of a loop in the center of the device prevents the likelihood of slipping in the cherklej put into it in one of two directions (proximal or distal) and eliminates the risk of secondary displacement of the bone fragment.

2) The lattice and the multi-plane nature of the device provide, on the one hand, minimal contact with the bone, and, on the other hand, the longitudinal direction of this contact (in accordance with the longitudinal orientation of the blood vessels supplying the bone), which excludes strangulation of the femur over its entire circumference and minimizes bone ischemia under the metal.

3) An increase in the metal-bone contact area, which, along with the previous paragraph, reduces bone ischemia under the osseous metal structure (wire cerclage and the proposed device).

4) The exclusion of the cerclage loop from falling into the gap between the main bone fragments with the expansion of the fracture gap, loss of stability of osteosynthesis and inhibition of reparative osteogenesis.

5) The springiness of the device, due to its arcuate curvature, despite bone resorption at the junction with the metal, ensures constant metal-bone contact and stability of osteosynthesis for the entire period of fracture consolidation.

6) The simplicity of manufacturing the device and the lack of need for additional material and tools, in addition to what is in every traumatology and orthopedic department (Kirschner spokes and pliers).

Thus, the proposed device is simple, efficient and economical, and its use allows to achieve improved treatment results for patients with comminuted fractures of the femur.

Information sources

1) V.P. Okhotsky, A.G. Suvalyan. Intramedullary osteosynthesis with massive metal pins. - M .; Medicine, 1988 .-- 128 p.

2) I.A. Movshovich. Operative orthopedics. - M. - 1994, - 446 p., - S.35-44.

3) Traumatology and orthopedics / A guide for doctors: In 3 volumes. T.1. Ed. Yu.G. Shaposhnikova. - M .: Medicine, 1997 .-- 656 p., - S.482-505.

4) B. Boychev, B. Conforti, K. Chokanov. Operative orthopedics and traumatology. - Sofia. - 1962, - 832 s., - S.84-92 - prototype.

Claims (1)

A device for fixing a bone fragment to its bed during retrograde intramedullary osteosynthesis of comminuted fractures of the femoral diaphysis, characterized in that it is made of a curved Kirschner knitting needle, which has a loop for wire cerclage and step bends located on both sides of the last with an indentation to form a structure with three longitudinally arranged fragments for contact with the osseous bone, while the loop is located on the middle fragment in the center of the device, and with the knees connecting the pope echno three longitudinally spaced fragment, the latter being shifted in the direction of the loop to prevent contact with the bone and arcuately curved to springiness.

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