RU2338480C2 - Method of osteosynthesis of splintered fracture of femur diaphysis - Google Patents

Abstract

FIELD: medicine; traumatology.

SUBSTANCE: preliminary, before placing the shaft in a bone, form apertures in it for the subsequent placing of a stirrup of a material with shape memory property through the shaft. The apertures in the shaft form with diameters exceeding diameters of the stirrup legs, and close to fracture border with deviation from a break zone on 15-20 mm in the both sides from a fracture line. Thus one of the apertures has the correct round form, other aperture - the extended form along the shaft with possibility of moving of the stirrup after its installation through the shaft towards the fracture. Carry out open comparison of fragments of the bone. Establish the shaft intramedullary under the X-ray control. Project the apertures executed in the shaft on the bone, fix these places and form channels for passage of legs of the fixing stirrup perpendicularly to the shaft direction through them and through cortical layers. Pass the stirrup legs through the formed pairs the of the conterminous apertures "shaft-bone", establishing the top leg in the top part of the extended aperture. Choose sufficient extent of a stirrup for full covering of the external basis of a bone splinter along the cortical layer.

EFFECT: stable bracing and constant uniform compression of osteal fragments.

1 dwg, 1 ex

Description

The invention relates to medicine, namely to traumatology, and can be used in the surgical treatment of fractures of the diaphysis of the femur and other comminuted fractures of long bones in specialized trauma departments of hospitals in the healthcare system.

A known method for distally blocking cannulated rods during intramedullary osteosynthesis of long tubular bones, including a closed reposition of bone fragments of a long tubular bone. A cannulated rod of a certain length is inserted along the guide needle into the medullary canal. Using a prepared distal target, a channel for locking screws is formed in the bone with a drill. The passage of the drill through the openings of the working end of the cannulated rod is controlled by a spoke inserted into the channel of the rod. When the direction of the channels corresponds to the holes on the working end of the rod, locking screws are introduced, which also control the spoke introduced into the rod channel. In case of deformation during insertion of the working end of the cannulated rod, the correct channel direction for the locking screws is determined (RF patent No. 2252723, class A61B 17/72, 17/88. Publish. May 27, 2005).

But this method is technologically complicated, does not allow guaranteed distal blocking, does not provide constant compression in the comminuted fracture zone, and does not guarantee the holding of fragments from lateral displacement under axial load of the damaged segment.

There is also known a method of osteosynthesis using a bracket made of a material having a shape memory effect (USSR author's certificate No. 1152582, class A61B 17/58. Publ. 30.04.85 Bull. No. 16).

However, this method does not provide sufficient stability for fixing the main fragments in the axis of the damaged segment and allows lateral displacement of the fragments under the axial load of the segments.

Closest to the proposed in its technical essence is a method of combined osteosynthesis, including the installation of staples with a shape memory effect with the location of its legs in the cortical layers of both major bone fragments. At the same time, holes in bone fragments are drilled so that the legs of the staples lie next to the intramedullary pin (“Guide to the osteosynthesis of fixators with thermomechanical memory.” Part 1. Edited by the doctor of medical sciences V.V.Kotenko. - Novokuznetsk, 1996) .

But since the legs of the brace pass through the cortical layer next to the intramedullary pin and are fixed only to one layer in front or behind the pin, reliable axial fixation of the fracture is not always ensured.

The task to which the invention is directed is to ensure reliable fixation, as well as constant and uniform compression of fragments of the fracture zone with limited lateral displacement of the fragments during their axial load.

The problem is solved in that in the method of combined osteosynthesis, including the installation of a bracket from a material with a shape memory property, prior to installing the pin in the bone, holes are made in it for subsequent installation through the bracket pin. In this case, the holes in the pin are made with diameters exceeding the diameters of the legs of the bracket, and near the boundary of the fracture with a 15-20 mm deviation from the fracture zone on both sides of the fracture line. Moreover, one of the holes is made of the correct round shape, and the other hole is elongated along the pin with the possibility of moving the legs of the bracket with a fragment along the pin towards the fracture. Then an open comparison of bone fragments is carried out, an intramedullary pin is installed under x-ray control, the holes made in the pin are projected onto the bone and these places are fixed (identified). Create channels perpendicular to the direction of the pin through them and the cortical layers for the passage of the legs of the fastening bracket. Pass through the formed pair of matching holes "pin-bone" legs of the bracket, installing one of them in the upper, remote from the fracture, part of the elongated hole. In this case, the length of the staple is chosen sufficient to completely capture the outer base of the bone fragment along the cortical layer (see drawing).

Preliminary, prior to installation in the bone, making holes in the pin serves for subsequent installation through the staple pin.

And the excess of the diameters of the holes in the pin diameters of the legs of the bracket allows you to freely, without difficulty, enter the legs of the bracket into these holes.

The location of the pin holes near the boundary of the fracture with a deviation from the fracture zone by 15-20 mm on both sides of the fracture line contributes to the reliable capture of the fracture zone with the provision of axial and lateral compression of the main fragments and fragments.

The implementation of one of the holes of the correct round shape, which is the supporting part of the structure, helps to ensure compression of the main fragments and fragments, derotation of the segment.

And making another hole elongated along the pin makes it possible to move the bracket with the other main fragments along the pin towards the fracture.

An open comparison of bone fragments leads to the most accurate reduction.

Installation under hardware control (for example, x-ray) of the pin intramedullary provides the conditions for intraosseous fixation of the main fragments and fragments.

And projecting the holes made in the pin onto the bone and fixing these places allows you to precisely determine the place for drilling the diaphysis under the legs of the bracket.

The creation of the channels perpendicular to the direction of the pin through the holes and cortical layers is intended to pass through the formed pairs of matching pin-bone holes of the legs of the fixing bracket.

The installation of the second leg in the upper part of the elongated hole remote from the fracture provides the conditions for moving the staple leg with a fragment to the side of the fracture zone.

The selected length of the staple is sufficient for complete capture of the outer base of the bone fragment along the cortical layer.

The technical result consists in stable fixation of the fragments making up the comminuted fracture, and derotation of the segment.

The method is implemented as follows.

In the preoperative period, the X-ray patterns in two projections of the damaged bone determine the localization and extent of the comminuted fracture zone, as well as the place of its assumed position, taking into account the intramedullary pin in the medullary canal. On the pin, selected along the length and width of the medullary canal, mark the position of the holes for the legs of the contracting bracket with thermomechanical shape memory. The position of the holes is marked taking into account the tolerance on both sides of the boundaries of the fracture zone of 15-20 mm. The diameter of the holes in the pin exceeds the diameter of the legs of the bracket by 0.5-1.0 mm. The tightening bracket is selected so that the length of its longitudinal part in the straightened, under cooling conditions, corresponds to the distance between the holes in the pin. Moreover, one of the legs of the tightening bracket is located in the hole of regular, round shape, and the other in the projection of the hole of elongated, oblong shape. In this case, in the last hole, the gap is shifted towards the fracture zone for compression.

Preoperative sterilization is standard. To perform the osteosynthesis operation, the patient is placed on the operating table on a healthy side. The treatment of the skin of the thigh to be operated is carried out according to the usual rules of asepsis. Next, access to the fracture zone is carried out, the ends of the main fragments are isolated and the intramedullary pin is inserted retrograde or antegrade, with a bone marrow canal reaming, if necessary. In this case, the pin should occupy a position in which the longitudinal axis of the holes made in it were perpendicular to the base of the fragment. At the next stage, an x-ray is performed in two projections of the femur with the application of metal marks on the surface of both main fragments at a distance of 1.5-2.0 cm from the fracture zone. According to this x-ray or under the control of an electron-optical transducer (EOP), the cortical layer of the femoral diaphysis is drilled with a drill whose diameter corresponds to the diameter of the hole in the pin. Drilled so that, having passed the hole in the pin, drill a diametrically opposite cortical layer of the femur. And in the area of the hole of an elongated, elongated shape, the above-described drilling is performed at a point projecting onto the part of this hole farthest from the fracture zone. Then the tightening bracket is cooled in a standard way with chloroethyl or nitrous oxide. In a cooled state, the bends are straightened, and the legs of the bracket are bent from the extended part to a right angle. And in this position, the legs are inserted into the matching pin-bone holes, and the extended part of the bracket is placed above the intermediate fragment (drawing). Under the influence of body temperature, the temperature of the bracket with thermomechanical memory rises and, having taken its initial position, it compresses the main fragments along the long axis of the thigh, while simultaneously holding the intermediate fragment in the repositioned position.

Clinical example.

Patient Sh., 21 years old, medical history No. 3057. As a result of a transport injury, on October 31, 2006 he received a comminuted fracture of the diaphysis of the femur with displacement of fragments (32 V according to the AO / ASIF classification). November 10, 2006 the operation was performed: an open reposition of fragments of the femur, intraosseous osteosynthesis of the pin. Before installing the pin, two holes were drilled in it so that when the pin was inserted into the medullary canal, they were indented from the fracture zone by 20 mm on both sides of the fracture line. Further, under the control of the image intensifier tube, the cortical layers were drilled through the holes in the pin through the holes in the pin. Then, legs of a bracket straightened in cooling conditions made of titanium nickelide were introduced into the pin holes. As it warmed up in the operating wound, the staple contracted along the long axis of the thigh. The hip fragment was fixed laterally with the long part of the staple and was tightly held between the main fragments. As a result, stable osteosynthesis was achieved with the correct anatomical relationship of fragments of comminuted fracture of the femoral diaphysis.

Claims (1)

A method for osteosynthesis of a comminuted fracture of the femoral diaphysis, characterized in that, prior to installing the pin in the bone, holes are formed in it for subsequent installation through the staple pin from the material with the shape memory property, while the holes in the pin are formed with diameters exceeding the diameters of the staple legs , and near the boundary of the fracture with a distance of 15-20 mm from the fracture zone on both sides of the fracture line, one of the holes has a regular round shape, the other hole has an elongated shape along the pin with the ability to move the bracket after it is inserted through the pin towards the fracture, then openly compare bone fragments, install the intramedullary pin under x-ray control, project the holes made in the pin onto the bone, fix these places and form the channels perpendicular to the direction of the pin through them and through the cortical layers for the legs of the mounting bracket to pass, and the legs of the bracket are passed through the formed pairs of matching pin-bone holes, placing the upper leg in the upper part of the elongated holes, and the length of the bracket is selected sufficient to completely cover the outer base of the bone fragment along the cortical layer.