RU2632508C1 - Device and method of blocked external osteosynthesis of condylar fractures of long bones - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: device for blocked external osteosynthesis of condylar fractures of long bones includes a plate, cancellous and cortical screws. The plate is made longitudinally curved in shape of the synthesized condyle and narrowed to the end along the length with the upper edge twice as wide as the lower one, with pointed lateral edges and tooth cutting along the edges for contact with the bone, with holes made top-down first in two transverse rows: in the top row with three, and in the bottom row with two. Between the two holes of the second row there is a hole for Kirschner's wire. The end holes of the first row of the plate are cut at an angle of 10° to the sides, and the average one is perpendicular to the plate, without thread. The two holes of the second row of the plate are cut at an angle of 10° to the sides. One longitudinal row of holes running along the top of the plate, which are cut alternately left-and-right at an angle of 10°, is located along the center of the plate curvature downward with an indent to a certain distance from the transverse ones. On the upper half of the plate thickness, the holes are made cone-shaped with a conical screw thread, and the other half of the plate thickness is smooth with diametre providing a passage, creating a tight contact in the threadless part of the screw. The cortical screw is made with a tapered thread under the cap on the half of the head, coincides with a similar thread of the upper half of the plate thickness. When screwing the screw bears against the edges of the plate hole and protrudes beyond its lower edge, and the length of the screw consists of the following: the screw cap, the thickness of the plate at an angle and 2 mm of deviation from the plate, and the diametre of the bone revealed on the X-ray diffraction pattern. The upper screws are cancellous, and the lower ones are cortical - without threads on their body, which is cut only at the end of the rod by 1/3 of the length. The method of blocking osteosynthesis of metaphysial fractures of long bones consists in repositioning and fixing bone fragments and in using a plate which is placed on the fracture site. The fragments are reduced and the Kirschner's wire is inserted through the hole for the wire. Then, a hole is drilled in a bone through the middle hole of the plate of the upper row and the plate is fixed, and then the screws are inserted into the side holes of the upper row in the plate, then the screws of the second row are inserted, and when confirming the correct position of the fragments, the screws are inserted into the diaphyseal part of the damaged bone, the Kirchner's wire is removed.

EFFECT: inventions provide the reliable fixation, minimum contact of the plate and bone surface, eliminating a risk of bed sores and disturbed repair process, simplifying the fixation procedure.

2 cl, 7 dwg

Description

The invention relates to medicine, namely to traumatology, and is intended for the treatment of condylar fractures of long bones, such as the humerus, femur of the tibia.

Known system of lockable plates POLYAX.

Surgeons - designers:

Lawence Bone, MD, George Haidukewych, MD, Roy Sanders, MD.

POLYAX. Wide-angle space. Surgical technique.

OSTEOSYNTHESIS OF THE PROXIMAL DEPARTMENT OF THE TIBERA BY THE LOCKING PLATE. De Puy. a Gohnson Gohnson compani. Registration certificate No. FSZ 2007/00362.

“The POLYAX lockable plate system is designed to provide the surgeon with the maximum possible choice of screw design options: lockable with a fixed angle, lockable with a variable angle and non-lockable. As a result, fixation is performed taking into account the specific features of a particular fracture, the properties of the bone substance and the anatomical conditions ...

The screw is fixed by screwing it directly into the plate hole (fixed-angle options) or into the patented polyaxial bushings (variable-angle design) located in the plate. The locking part of the screw consists of a three-way tapered thread on the screw head, designed to engage with a plate or sleeve. The bushings allow you to fix the screws at the desired angle within 30 degrees. "Non-locking screws are installed in holes with a given angle or in polyaxial bushings."

Disadvantages:

1. A large area of contact between the plate and the bone surface is preserved, creating a threat to the development of necrosis and the inflammatory process of the bone with a violation of the reparative process in the fracture area;

2. The lack of universalization of the use of the plate, that is, for each segment and even the localization of the fracture, a separately manufactured plate is required;

3. The reliability of rotation of the spherical sleeve in the plate is not ensured.

We consider important the information on improving the screw for osteosynthesis of metaphysical fractures, reflected in patent No. 920085 Gimmelfarb A.L. "A device for osteosynthesis containing a plate with a groove made in radius and with threaded holes located on both sides of the midline, and fixation elements, characterized in that the axis of the holes are located along the radii of the groove of the plate, the fixation elements are made in the form of smooth rods with cylindrical heads having a slot and a thread corresponding to the thread of the holes, while the depth and width of the thread groove closest to the top of the head gradually decrease, disappear, while maintaining its pitch.

We consider it a serious drawback that there is no opposite fixing support of the screw with the walls of the bone hole, which does not allow the plate to be held with a designated purpose and a stable place. "

It is clear that a threaded rod is not able to possess the ability to hold the plate in a given fixing state, as a result, the synthesis is loosened and the stability of synthesis is violated. In addition, in the tubular bones, places for fixation are the cortical layers (entry and exit of the screw).

At the same time, there is a strong opinion about the influential screw-plate relationships reflected in patent No. 2138222 (RU).

“The screw for osteosynthesis consists of a threaded part, a neck and a head. The threaded part starting from the end of the screw is made with an outer diameter of 3.5 mm, an inner diameter of 3 mm, a pitch of 2.5 mm, a special profile of turns with a front angle of 5 ° and a rear angle of the profile of turns of 25 °, into the inner diameter of a thread with a radius of R 0.8 mm and into the internal diameter of a thread with a radius of R 1.2 mm, respectively, with a radius of R 0.1 mm at the tip of the profile R 0.1 mm. The threaded part is separated from the hemispherical head with an internal turnkey hexagon hole, a screw neck with a diameter of 4.5 mm and a length of 3.4 mm. The technical result of the invention is to ensure the creation of such a technological design of the screw, which will allow atraumatic insertion of the screw into the drilled hole without a special tap, as well as providing compression between the plate and the bone ... "

It should be noted that with blocked osteosynthesis, compression of the plate with the bone is not considered mandatory.

The closest is the method of surgical treatment of proximal fractures of the shoulder.

Patent WO 2013073994 A1, 2013 can be used as an analogue. “A retainer for osteosynthesis of fractures of the proximal metaepiphysis of the humerus in the form of a plate consisting of a diaphyseal and metaepiphyseal parts with threaded holes for insertion of lockable screws, characterized in that the metaepiphyseal part follows the shape of a large the proximal part of the humerus and contains an upper opening for insertion of a locked screw. "

Its main feature is the repetition of the shape of a large tubercle, which can be considered a negative phenomenon.

Firstly, it is difficult to choose or fit according to the form proposed by the author, and secondly, a fit-shaped retainer and laid on the fracture area creates conditions for disturbance of nutrition of underlying tissues and the occurrence of pressure sores.

Or another analog. Shapovalov V.M. et al. Fundamentals of Internal Osteosynthesis. 2009, p. 95-96. "Osteosynthesis with a proximal shoulder plate with angular stability of screws (LPHP - Locking proximal humeral p1ate). The plate is used for fractures of type A2, A3, B and C and in patients with osteoporosis. ... Perform an open reposition, fix the fragments with knitting needles, drill holes through the plate. Fixing the plate with screws with angular stability, while the design of the plate allows for the introduction of up to four screws into the head, but usually three are enough. Fixation to the diaphysis is carried out by 2-3 screws. In addition, the design of the plate allows the use of cortical screws in the diaphyseal part if it is necessary to fix fragments or perform reposition using the plate. In addition, plates with an elongated diaphyseal part can be used to extend the fracture line to the diaphysis of the humerus. In the early postoperative period, shoulder immobilization is carried out with a scarf. "

1. A large area of contact between the plate and the bone surface is maintained.

2. At the places of the recesses, the plate becomes less strong and its fractures occur in the marked places.

3. A significant limitation of the plane of the screw.

4. The upper edge of the plate is rounded, as a result, only two holes are placed, which should be quite wide for holding the spongy screw.

5. Limited the ability to capture the width of the damaged condyle.

The table of the claimed designs with analogues

1. 1st analogue:

POLYAX lockable plate system. The purpose of the prototype device: the implementation of the blocked osteosynthesis of the metaphyseal region of long bones. It is carried out using embedded bushings that have the ability to change the angle range during osteosynthesis, and the cone-shaped screw cutting of the sleeve and screw allows for locking blocking of the plate.

2. 2nd analogue. Fixing the plate with screws with angular stability, while the design of the plate allows for the introduction of up to four screws into the head, but usually three are enough. Fixation to the diaphysis is carried out by 2-3 screws.

3. 3rd analogue. The fixing elements are made in the form of smooth rods with cylindrical heads having a slot and a thread that mate with the holes, while the depth and width of the thread groove closest to the top of the head smoothly decrease, disappear, while maintaining its pitch.

The claimed invention: a device and method of blocked immersion osteosynthesis of condylesic fractures of long bones (described further in the text of the description of the invention).

A preliminary version of the formula of the proposed device and method

Device and method for blocked submersible osteosynthesis of condylar fractures of long bones

1. A device for blocked immersion osteosynthesis of condyle fractures of long bones, including a plate curved from above in the shape of a bone, with fan-shaped holes in the proximal section with and without an internal taper thread, and also located along the plate downwards, there are also bushings with an internal taper thread and screws with a taper thread on the head with the ability to change the angle of inclination of the screw, and free from thread, characterized in that the plate is conical in length; the upper edge is twice as wide as the lower one, longitudinally curved in the shape of the synthesized condyle and across with pointed lateral edges and serrated cutting, with holes firstly laid from top to bottom in two transverse rows; the top row is three, and the bottom two, and then indented from them, one row of holes is located down the center of the curvature of the plate: the extreme holes of the first row of the plate are cut at an angle of 10 degrees to the sides, and the middle is perpendicular without thread; two holes of the second row of the plate are cut at an angle of ten degrees to the sides, between which a small hole for the spoke, drawn from the bottom up at an angle of 15 degrees, and the lower holes, departing some distance from the transverse, are located on the top of the plate, and they are cut alternately, then to the left then right at an angle of 10 degrees; moreover, on the upper half of the plate a hole with a cone-shaped screw thread, and the inner half of the hole in the thickness of the plate is a smooth length equal to the length of the threadless part of the screw head; the plate contacts the bone with pointed edges with serrated cutting; a screw with a cone-shaped thread under the head equal to half the plate thickness, respectively threaded in its upper part, and the lower part of the screw length is threadless, but when screwing it tightly adheres to the edges of the plate hole and extends beyond its lower edge, and the screw length is: screw head, plate thickness at an angle and 2 mm of exit beyond the plate, and bone diameter detected on x-ray; the upper screws are spongy, and the lower ones are cortical - without thread on their body, which is cut at the end of the shaft 1/3 of the length.

2. The method of blocked osteosynthesis of metaphysical fractures of long bones, which consists in reposition and fixation of bone fragments, characterized in that they use a cone-shaped plate, which is placed on the fracture area, after reposition of the fragments and insert the Kirschner needle through a small hole in the second row, then drill a hole into the bones through the middle hole of the plate of the upper row and fix it, and then insert the screws into the side holes of the upper row in the plate, and insert the screws of the second row, and upon confirmation of correctness the fragments of the fragments tighten the diaphyseal screws.

Technical result

The technical result of the present invention is the development of the operational and functional properties of the plate and screws for blocked osteosynthesis of metaphysical fractures: ensuring reliable fixation, minimal contact of the plate with the bone surface, eliminating the occurrence of pressure sores and disruption of the reparative process, simplifying the operation of osteosynthesis. The noted technical result is achieved by changing the shape of the plate, the location of the holes on it and the shape of the hole of the plate, and use, and the pointed edges of the plate with gear cutting create reliable stability of the plate with the exception of its extensive contact with the bone and the use of a screw with a screw thread in the head and in the end its parts are 1/3 of the length, without thread in the middle of the screw body.

Justification of compliance of the invention with the criterion of "inventive step".

No signs are known from the prior art:

1. The plate is bent across with a bending radius of the plate equal to the width of the plate, which creates a constant optimal gap between the plate and the bone when using different widths, and the longitudinal edges of the plate are pointed with serrated cutting.

2. The angular direction of the holes in the threaded plate, with the corresponding thread on the screw head and a thread-free section, which creates reliability and angular stability of the screw.

3. Universal use of the plate, and differences in use depend only on the location (size) of the condyle.

4. A screw with a cone-shaped thread on the head and end part, in the absence of thread on its trunk, provides a more reliable fixation.

5. The plate is conical in shape.

The proposed device is presented in FIG. 13.

FIG. 1. Device for blocked immersion osteosynthesis.

FIG. 3. Device for blocked immersion osteosynthesis - a screw for osteosynthesis of condylar fractures.

The osteosynthesis of metaphysical fractures of long bones is reflected in: Fig. 4, FIG. 5, FIG. 6, FIG. 7, FIG. 8.

FIG. 4. The scheme of the operation of osteosynthesis of a fracture of the head of the humerus.

FIG. 5. Scheme of osteosynthesis of the distal radius

FIG. 6. Scheme of operation: osteosynthesis of a fracture of the distal metaphysis of the femur.

FIG. 7. Scheme of operation: osteosynthesis of a fracture of the proximal tibia metaphysis.

FIG. 8. Operation scheme: osteosynthesis of a distal metaphysis fracture of the tibia.

Thus, the proposed device for blocked immersion osteosynthesis of condyle fractures consists of a cone-shaped plate bent transversely - 1 with a bending radius equal to the width of the plate, to ensure optimal clearance with the bone surface, with pointed longitudinal edges and serrated cutting - 5 and holes cut under in a corner with a conical screw thread on top, arranged in two rows, the upper row - 2 three holes, and the second horizontal row - 3 two holes, and a small hole - 6 between them, and the lower opening tii - 4, going along the top of the curvature of the plate. With screws - FIG. 3 (the upper ones are spongy, the lower ones are cortical), with a conical thread on the half of the head with a key slot - 7, and a head cap - 8, with a thread under the conical head - 9, the threadless part of the head and barrel of the screw - 10, and with a thread at the end of it - 11. The proposed design is universal for the treatment of fractures of any location of the condylar fractures.

Variant of using the proposed device

The proposed device can be used with the simplicity of traditional bone osteosynthesis, but with an efficiency exceeding the blocked devices of the latest generation, which greatly increases the effectiveness of treatment of patients with condylar fractures of long bones.

Schematically, the use of the proposed device can be represented as follows:

- select the necessary plate - 1 (respectively the diameter of the bone) and condylar angle obtained from x-ray,

- performing surgical access - an incision is made according to existing surgical rules at the level of a bone fracture,

- secrete bone fragments with the release of hematoma or connective tissue formations,

- eliminate soft tissue interposition,

- carry out the reposition of bone fragments,

- set the plate - 1 on the fragments at the fracture level,

- through a small hole - 6 spend Kirschner retaining needle. When confirming the correct position of the fragments, through the middle hole of the upper horizontal row - 2, the plate, enter the fixing screw,

- confirming the correct position of the fragments, the remaining screws and screws of the second row - 3 are inserted, with the help of a drill, holes are made in the bones and screws are made - Fig. 3, and screw until the thread of the head contacts the thread of the plate.

Check the state of comparability of the fragments and after drilling the bone through the lower holes - 4 and installing screws in them, and monitoring the position of the fragments, all screws are screwed tightly until the screw head coincides with the bed of the plate.

- Immobilization of the limb, depending on the nature of the fracture and the reliability of the performed osteosynthesis. Management without immobilization is possible.

Claims (2)

1. A device for blocked immersion osteosynthesis of condyle fractures of long bones, including a plate, spongy and cortical screws, the plate is made longitudinally curved in the form of the synthesized condyle and narrowed to the end along the length with the upper edge twice as wide as the lower edge and with pointed lateral edges and serrated at the edges for contact with the bone, with holes first applied from top to bottom in two transverse rows: in the upper row with three, and in the lower with two, between the two holes of the second row a hole under the Kirschner needle, the extreme holes of the first row of the plate are cut at an angle of 10 ° to the side, and the middle perpendicular to the plate, without thread, the two holes of the second row of the plate are cut at an angle of 10 ° to the side, at the center of curvature of the plate down with an indent some distance from one transverse row of longitudinal holes located along the top of the plate is located, alternately cut to the left, then to the right at an angle of 10 °, moreover, on the upper half of the plate thickness, the holes are made cone-shaped with a cone-shaped screw thread, and others the half of the thickness of the plate is smooth with a diameter that allows it to pass, creating a tight contact in the screwless part of the screw, the cortical screw is made with a conical thread under the cap on the half of the head, coincides with the same thread of the upper half of the plate thickness, tightens to the edges of the plate hole when screwing and leaves beyond its lower edge, and the length of the screw is: the screw head, the thickness of the plate at an angle and 2 mm of exit beyond the limits of the plate, and the diameter of the bone revealed on the x-ray, the upper vi nts are spongy, and the lower ones are cortical, without thread on their body, which is cut only 1/3 of the length at the end of the shaft. 2. The method of blocked osteosynthesis of metaphysical fractures of long bones, which consists in reposition and fixation of bone fragments, which consists in using a plate according to claim 1, which is placed on the fracture area, the fragments are repaired and the Kirschner spoke is inserted through the knitting hole, then the hole is drilled in the bone through the middle hole of the plate of the upper row and fix the plate, and then insert the screws into the side holes of the upper row in the plate, and then insert the screws of the second row, and when confirming the correct position, breaking screws are inserted into the diaphyseal part of the damaged bone, and the Kirschner needle is removed.

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