RU2663636C1 - Device for external fixation for children for transosseous osteosynthesis - Google Patents

Abstract

FIELD: medicine.SUBSTANCE: invention relates to medicine. Device for external fixation for children for transosseous osteosynthesis comprises supports, distraction rods for connection of supports, spokes, bolts – spoke fixators, clamps for distraction rods or bolt – spoke fixators and nuts for distraction rods and bolts – spoke fixators. Supports in cross-section are hexagonal. Each clamp consists of two joining elements to cover the support on two opposite sides. Each of the joining elements to be joined has, at one end of the joining side, a groove for locating the support, and at the other end it has a through hole for the distraction rod or bolt – spoke fixator. Axis of said hole is perpendicular to the axis of the groove. One of the holes of the joining elements of the clamp on the non-joining side has a chamfer. When the elements are joined, the axes of said holes are coaxial, and the grooves are opposite one another. Bolt-spoke fixator is made in the form of a rod with bent threads and a hexagon head. Point of transition of the rod to the head is made in the form of a conical rim for locating the hole of the element of the clamp in said chamfer. Groove is cut out for the spoke on the conical rim.EFFECT: invention allows fixing bone fragments in a given position, creating compression or distraction forces between bone fragments, with a lighter weight and ease of use.18 cl, 9 dwg

Description

Technical field

The technical solution relates to medicine, to the field of traumatology and orthopedics, and in particular to the construction of devices for bone osteosynthesis using external (external) transosseous fixation.

State of the art

External fixation devices (AVF) are widely known and used in clinical practice for bone osteosynthesis, in particular in the treatment of fractures and deformations of the bones of the lower leg, thigh, shoulder, and forearm in both adults and children.

Various AVFs are known in the art.

Known apparatus G.A. Ilizarova for transosseous osteosynthesis (source [1]: SU 1055499). Ilizarov’s apparatus is a set of standard parts (flat rings, half rings, spokes, threaded rods, bolts, nuts, brackets, special fixers) of various sizes, made in the form of a set of parts from which you can assemble many different, simple and complex systems for external fixation bones, apparatuses and devices for solving specific medical problems. The Ilizarov apparatus excludes the time required to manufacture specific parts to order for a particular patient, it has versatility and solves a wide range of applied problems of traumatology and orthopedics. There are sets of parts for the Ilizarov apparatus for operations on the hip, pelvis, lower leg, foot and lower leg, shoulder, forearm, collarbone, spine, hand, adult and children's sets (source [2]: electronic catalog of FSUE products “Experimental plant of the RTC“ WTO ”named after Academician G. A. Ilizarov of the Ministry of Health of Russia, available on the company's website http://www.ozrncvto.ru, in the“ products ”section of the“ Tools and Devices for Transosseous Osteosynthesis in G. A. Ilizarov "," Sets of parts of the Ilizarov apparatus. "Access mode http://www.ozrncvto.ru/blank-sto5i). The Ilizarov apparatus contains supports made in the form of flat half rings (1/2 rings, 5/8 rings) and / or flat rings with holes, arcs, with spokes and / or screw rods mounted on them, interconnected by distraction rods (threaded rods, telescopic rods) and forming blocks of fixation and reposition. Knitting needles and rods screws fixed on supports. The apparatus may contain articulated units and reposition units that are assembled from brackets, bolts, threaded rods, nuts. The set of parts contains bolts M6 × 1, bolts - special fixators, clamps ʺГ зажим-shaped, nuts M6 × 1, arcs (simple half rings and special), rings (inner diameter from 100 to 240 mm), brackets with a threaded hole M6 × 1, brackets with threaded shank M6 × 1, straight strips, beams, threaded rods M6 × 1, washers F7, conical washers, washers with a groove, spherical washers, radial attachments. Parts are made of stainless steel or titanium alloy. The supports are made in the form of flat rings and half rings (1/2 part of the ring), with through holes evenly spaced in one row, the longitudinal axis of the holes are radially symmetric to the longitudinal axis of the ring, while the supports in the form of half rings contain bends and can be connected so that form a ring.

The prior art apparatus for external transosseous fixation of bones, the apparatus of Volkov-Hovhannisyan (source [3]: RU 35711). The apparatus [3], like the Ilizarov apparatus [1], contains supports made in the form of flat brackets (half rings, 5/8 rings) with holes, connected by threaded rods to nuts. On the supports, knitting needles and / or rods of screws are fixed. The apparatus [3] contains four supports arranged in series. The two middle supports are connected by means of reposition units. Supports (staples) are made of composite x-ray transparent carbon fiber reinforced multilayer material.

Devices [1; 2; 3] they allow to stabilize bone fragments, create distraction and compression between them, provide the necessary fixation stiffness, but do not allow to fix a spoke or a threaded rod anywhere on a support, and also has excess weight embedded in the construction of supports. Supports [1; 2; 3] ensure the rigidity of the AVF structure, and stable fixation of the fixed bone fragments. Threaded connections (screw-nut) provide distraction and compression forces between the supports.

The design of the apparatus [1; 2; 3] involves fixing the distraction rods, bolts, brackets, special fixators in the holes made in the support. In the supports of devices [1; 2; 3] there is only one row of mounting holes, with which the doctor must fix the knitting needles or brackets. Fixing elements on the support should be carried out in a predetermined place (not arbitrarily). Therefore, difficulties arise in fixing the spokes and installing articulated joints when connecting the supports, which affects the convenience of the doctor when correcting individual components of the deformation. Support apparatus [1; 2; 3] ring with many mounting holes and make up the bulk of the material of the apparatus. The cross section of the supports is a rectangle. The surface of the support is penetrated by mounting holes, weakening its cross section in terms of strength. In order to provide the necessary rigidity and strength, such a support should be made not less than a certain width and thickness, so that it was possible to make mounting holes in it and maintain sufficient rigidity, as a result of the support wide and massive. At the same time, when attaching rods and knitting needles, only a smaller part of the mounting holes is used, and the surgeon must choose which hole to fix the needle to and reject its position, or draw the needle into the bone, taking into account the position of the holes in the support. In order to make mounting holes in the support, the width of its cross section and the volume of the material used are increased, but not all holes are used. As a result, the patient is forced to carry excess material on him, this causes an additional load on the musculo-ligamentous system of the injured limb, which is uncomfortable for the patient. For children, due to the small size of bones and muscles, to ensure comfortable treatment, the minimum possible weight of the apparatus is required, while ensuring freedom in choosing the place of fixation of the knitting needles on the support. In the apparatus, threaded (distraction) rods are made of metal, which makes the devices heavier and adversely affects x-ray studies. Devices [1; 2; 3] are not suitable for children, even sets of parts of the smallest standard size are inconvenient, not comfortable for small patients.

Known apparatus for external fixation (source [4]: patent US US 5443464). An external fixation system [4] for stabilizing bone fractures contains a main support in the form of a hexagonal (multifaceted) rod, an additional support made in the form of a ring of rectangular cross section connected to it by a clamp, and many bone fixation components (screw rods) movably attached to them clamps. The clamping mechanism comprises a clamping element and a ball collet with a hexagonal hole. The clamping element is adjustable in the longitudinal and transverse directions around the rod.

The apparatus [4] allows you to fix the components of bone fixation anywhere on the annular support, provides the necessary rigidity of fixation, but does not allow you to create distraction and compression forces between the supports. The size of the supports of the apparatus is not adapted to the size of the limbs in children. The clamps are bulky and increase the weight of the device. The support, made in the form of a rod, is metal, and covers the area of research during radiography. The device [4] is not suitable for use in children of younger and middle age groups, it is not comfortable for small patients.

Known compression-distraction apparatus for osteosynthesis of Kalnbers (source [5]: patent SU 1251892). The apparatus [5] contains annular supports of circular cross section connected by threaded rods mounted on the supports by means of clamps. On the supports, threaded needles are fixed by means of spokes. The clamps are made in the form of brackets with hook-shaped grips and a clamping screw. The spokes are made in the form of U-shaped staples with hook-shaped grips with pressure plates and a clamping screw.

The apparatus [5] allows you to create distraction and compression forces between the supports, allows you to fix the spokes anywhere on the support, but does not provide the necessary rigidity of fixation. The cross-section of the supports is round and the clamps, when loaded on the apparatus, rotate on the support. Also, under load, they can rotate on the support clamps for knitting needles. The friction forces arising between the clamp and the support are not sufficient to ensure the rigidity of the structure and the necessary stability of fixation of bone fragments. The size of the supports of the apparatus is not adapted to the size of the limbs in children. The device [5] is not suitable for use in children of younger and middle age groups, it is not comfortable for small patients.

Known compression-distraction apparatus Kalnbersa (source [6]: patent SU 1651885). The apparatus [6] contains support rings connected by smooth rods, clamps (clamps), knitting needles and spokes (clamps). Rings and rods made of the same rod of a multifaceted (six or octagonal) cross section. The polyhedra of the support rings are oriented in such a way that the two planes are perpendicular to the plane of the ring. The material for the manufacture is plastic, with the original rods reinforced with fiberglass. The clamps connecting the supporting rings and rods of the apparatus are made in the form of a cylinder with a persistent thread on the outer surface, and two mutually perpendicular slots made from one of its ends, a stopper with a notch along the welt mounted on the body by a thread, and a cross-shaped thrust plate. The supporting surfaces of the clamps adjacent to the rods and supports are multifaceted. Spokes are made similarly, but additionally contain a sliding liner of two pressure plates with internal jaws made of steel. All elements (except sponges) are made of plastic.

This analogue [6] is not a compression-distraction apparatus, it is only a fixing (stabilizing) apparatus. It does not allow to provide distraction or compression forces on bone fragments during fixation, since the supports are connected by smooth rods and there is no mechanism in the design that provides a metered approach or dilution of the supports. The knots for fixing the spokes and rods (clamps) are bulky, increase the total weight of the apparatus, consist of six parts, laborious in manufacturing. The analogue is completely made of plastic, which is favorable for x-ray studies but does not always provide the necessary strength and rigidity. Also, the analogue in size is not adapted to the size of the limbs in children.

A device for external fixation (source [7]: patent RU 109650). It contains supports made in the form of detachable flat rings with holes on which bone retainers and fastening elements are installed. The supports are interconnected by distractors made in the form of a rack with a threaded rod, at the ends of the distractor there are tacks for fastening to the supports by means of nuts. On the rings, between the outer edge and the holes on both sides, circular grooves for tacking are installed at the ends of the distractors. Distractor racks have a rectangular cross section, equipped with holes and two longitudinal grooves.

In the supports of this device [7], it is possible to mount the distractors to the support in an arbitrary place, which simplifies installation work. However, for fastening knitting needles, rods of screws (bone retainers), brackets, it is supposed to use mounting holes discretely located on the surface of the ring, i.e. fixing the elements on the support should be carried out in a predetermined place (not arbitrarily), which negatively affects the convenience of the doctor with the device. Flat annular supports involve the implementation of many mounting holes and grooves around the perimeter of the support, as a result, an increase in the width of the support, and therefore its mass, is required. The cross-section of supports of a rectangular shape, in order to provide the necessary rigidity and strength, such a support must be made not less than a certain width and thickness. In order to make mounting holes and a groove in the support, the width of its cross section and the volume of the material used are increased, but at the same time, when mounted, not all mounting holes and the surface of the groove are used. As a result, the patient is forced to carry an excessive mass of material necessary for the formation of unused ("extra") mounting holes and an unused surface of the groove, which causes an additional load on the musculo-ligamentous system of the injured limb, uncomfortable for the patient. For children, due to the small size of bones and muscles, to ensure comfortable treatment, the minimum possible weight of the apparatus is required, while ensuring freedom in choosing the place of fixation of the knitting needles on the support. The device [7] is not suitable for use in children of younger and middle age groups, it is not comfortable for small patients.

A device for external fixation (source [8]: patent US 5095919) containing annular supports equipped with grooves, supports using clamps installed bone clamps (spokes, rods, screws) and distractors. The supports are connected by distractors made in the form of threaded rods at the ends of which hooks (mounting parts) are fixed with nuts. The cross section of the support contains two opposite and symmetric polygonal (polygonal) parts connected by a jumper. Polygonal sections preferably have triangular sections. The hooks contain jaws having internal recesses arranged in accordance with the configuration of the surface of the support, so that they can be tightened and fixed on the support without the possibility of rotation around it. The hooks are fixed on the inside and / or outside of the support.

The device [8] contains annular supports having a significant width (more than 15 mm) in cross section. The cross section of the support in width is much larger than in height (thickness), this is due to the nature of the fastening of the grips and the way the two parts of the support are connected to each other. Grips (clamps) partially cover the surface of the support, clamping its outer or inner edge (edge). In the middle part of the cross section there is a jumper on the surface of which a hole is made necessary to install the bolt when connecting two parts into one ring support. The design of the device involves a flattened form of the support and its significant width, therefore, increases the mass. Grips clamp the support surface partially and have a low grip rigidity due to the small area of the covered surface. The size of the supports is not suitable for use in children whose limb size is smaller than the size of the limbs of an adult. The device [8] is not suitable for use in children of younger and middle age groups, it is not comfortable for small patients. To ensure comfortable treatment, the minimum possible weight of the supports is required, which is not provided in this device due to the geometric shape of the cross-section of the supports. In addition, metal parts are present in the device, which make the device heavier adversely affect x-ray studies. The essence of the technical solution.

The technical task is to expand the arsenal of technical tools used for bone osteosynthesis in children by external transosseous fixation, in particular in the treatment of fractures and deformities of the lower leg, thigh, shoulder, and forearm. In this case, the technical tool should provide the ability to fix the spokes and rods of screws (bone fixators) in an arbitrary position, provide the ability to transfer tensile / compressive forces (distraction / compression) to bone fragments, have a low weight, be lightweight relative to known analogues, and relatively simple to use, provide numerous and advanced assembly capabilities.

The technical result consists in the possibility of fixing bone fragments in a given position, the creation of compression or distraction efforts between bone fragments. At the same time, the external fixation device for children for transosseous osteosynthesis, with respect to well-known analogues, has a lighter weight and is easy to use.

The technical result is achieved by the fact that the child’s external fixation apparatus for transosseous osteosynthesis (AVF) contains supports, distraction rods for connecting the supports, knitting needles, spoke bolts, clamps for distraction rods or spoke bolts and nuts for distraction rods and spoke bolts. The supports in the cross section are hexagonal, each clamp consists of two abutting elements to cover the abutment from two opposite sides, each abutting element has a groove at one end of the abutting side for positioning the abutment, and at the other end has a through hole for the distraction rod or a special bolt, wherein the axis of the said hole is perpendicular to the axis of the groove, one of the holes of the mating clamp elements on the non-mating side has a chamfer when mating the axis elements of the said holes The holes are arranged coaxially, and the grooves are located opposite each other, the bolt-spoke is made in the form of a rod with a threaded thread and a hexagonal head, the place of transition of the rod into the head is made in the form of a conical rim for arranging the holes of the clamp element in the said chamfer, a groove is cut on the conical rim knitting needle.

The above essence provides a technical result, particular features of the AVF are defined in the following description.

It is envisaged that the distraction rods are made in the form of studs with an M6 × 1 thread, from 40 to 200 mm long. In this case, hinge assemblies, reposition units, for transverse, rotational, angular movement of the connected supports can be mounted on the distraction rods.

Preferably, the bone retainer clamping member on the outer surface comprises corrugation.

The support can be made by the team, and consisting of two parts connected end-to-end, so that the interface line forms a step. At the junction of the parts, a through transverse channel is made in which a fixing pin or bolt is installed. The end-to-end connection of the parts is made according to the “protrusion-groove” type, the interface line forms a step, and the surfaces of the protrusion and groove are made in such a geometric shape that prevents their mutual longitudinal displacement. For example, the surfaces of the protrusion and the groove may contain a thrust collar, or may be made with a slope, so that their geometric shape when joined end-to-end prevents the longitudinal movement of one part of the support relative to another. The support can be made in the form of a ring with an inner diameter in the range from 50 to 240 mm.

The fastening element is made in the form of a special fixing bolt containing a rod with a threaded thread and a hexagonal head. The transition point of the rod into the head is made in the form of a conical rim, on the surface of which a groove for the spoke is made.

The bone retainers are preferably made in the form of electropolished spokes with a diameter of 1 mm to 2 mm.

Supports, distraction rods, clamps, fasteners are made of corrosion-resistant alloy steel. It is envisaged that the supports, distraction rods, clamps, and fasteners can be made of VT6 titanium alloy, or of aluminum alloy. The distraction rods and supports can be made of a material that is transparent to x-rays, in particular, can be made of composite material, carbon fiber.

The developed technical solution allows to eliminate the disadvantages of analogues and solve the tasks set for the doctor.

The technical solution is illustrated by graphic materials:

FIG. 1 - AVF, general view (bone fragments are shown schematically);

FIG. 2 - external fixation apparatus, top view;

FIG. 3 - AVF, a view in section along section AA in FIG. 2;

FIG. 4 is a clip for an AVF knitting needle, a sectional view along section BB in FIG. 2;

FIG. 5 - AVF, side view;

FIG. 6 - ring support AVF with clamps, with spaced parts, a general view;

FIG. 7 - ring support AVF, with spaced parts, a common view;

FIG. 8 - ring support AVF, complete, side view (on the junction line).

FIG. 9 - AVF containing 4 supports and repositional nodes, side view.

Specification:

1 - support;

2 - distraction rod;

3 - the first part of the annular support;

4 - the second part of the annular support;

5 - clamp distraction rod;

6 - a nut;

7 - bone fixative;

8 - clamp bone fixation;

9 - fastener;

10 - threaded rod;

11 - head;

12 - conical rim;

13 - groove;

14 - the first element of the clamp;

15 - the second element of the clamp;

16 - groove;

17 - hole;

18 - corrugation;

19 - line mating parts of the support;

20 - channel (hole);

21 - a pin;

22 - bead;

23 - repositional node.

24 - bone fragments.

Implementation of a technical solution.

AVF (Fig. 1; 2; 3; 5) contains supports 1 (Fig. 1; 2; 3; 5; 6; 7; 8; 9) connected by distraction rods 2 (Fig. 1; 3; 5; 6; 9 ) The distraction rods 2 are made in the form of threaded rods with a metric thread M6 × 1, made of VT6 grade titanium alloy. The length of the distraction rods 2 shown in FIG. one; 3; 5 is 150 mm, to the arrangement shown in FIG. 9. The length of the distraction rods 2 is 80 mm. The support 1 is made of a VT6 grade titanium alloy, a ring, prefabricated, consists of two parts 3 and 4 (Fig. 7; 8) connected end-to-end. The support 1 is covered with a protective and decorative anode-oxide layer. The inner diameter of the support 1 is 113 mm, the roughness Ra of the outer surfaces of 0.32 μm. The support 1 in the cross section has the shape of a hexagon of size L = 7 mm (Fig. 4). The distraction rods 2 are connected to the supports 1 by means of clamps 5 (Fig. 1; 2; 3; 5; 6; 9) and nuts 6 (Fig. 1; 2; 3; 5; 6; 9). The distraction rods 2 by means of rotation of the nuts 6 have the ability to move relative to the clamps 5. The movement of the distraction rods 2 causes the mutual movement of the supports 1. On the supports 1 are mounted bone retainers 7 (Fig. 1; 2; 3; 5; 6; 9) made in the form of electropolished knitting needles with a diameter of 1.8 mm. Bone retainers 7 are mounted on supports 1 by means of clamps 8 (Fig. 1; 2; 3; 5; 6; 9) and fasteners 9 (Fig. 1; 2; 3; 5; 6; 9) made in the form of a special fixing bolt . The fastening element 9 contains a rod with a threaded thread 10 (Fig. 4; 6) and a hexagonal head 11 (Fig. 4; 6). The transition point of the rod 10 into the head 11 is made in the form of a conical rim 12 (Fig. 4; 6), on the surface of which a groove 13 (Fig. 6) is made under the bone retainer 7 (knitting needle). Each clamp 5 and 8 consists of two elements 14 and 15 (Fig. 4; 6), made of titanium alloy grade ВТ6, in the form of legs, equipped at one end with a groove 16 (Fig. 6), and at the other end with a hole 17 ( Fig. 6). Elements 14 and 15 of the clamps 5, 8 surround the support 1 from two opposite sides, while the holes 17 of the elements 14 and 15 are aligned. The threaded part of the distraction rod 2 passes through the holes 17 of the two elements 14, 15 forming the clamp 5 of the distraction rod 2. The bone retainer 7 is connected to the clamp 8 by the fastening element 9 with the nut 6. The threaded part of the fastening element 9 passes through the holes 17 of the two elements 14 and 15 forming clamp 8 of bone retainer 7. On the threaded part of the distraction rod 2 and the fastener 9, nuts 6 are installed. Element 14 of clamp 8 of the bone retainer 7 on the outer surface contains corrugation 18 (Fig. 6). The support 1 is made by the national team, and consisting of two parts 3 and 4 connected end-to-end, of the protrusion-groove type, so that the interface line 19 forms a step (Fig. 8). At the junction of parts 3 and 4, a through transverse channel 20 (Fig. 7) is made, in which a fixing pin 21 (Fig. 8) is installed, or a bolt. The surfaces of the protrusion at the junction of parts 3, 4 are sloped to form a shoulder 22 (FIG. 7), and the geometric shape prevents the longitudinal movement of part 3 relative to part 4. As shown in FIG. 9, the reposition units 23 can be mounted on the distraction rods 2 (Fig. 9), and the supports 1 in the AVF can be connected in blocks of two. The number of supports 1 used in AVF is selected depending on the medical tasks, the complexity of fractures and deformations of the bone.

Using a technical solution

When a bone fracture is mounted support 1 on a damaged limb. Set one support 1, at a distance of not less than 20 mm, from the fracture line, for each bone fragment 24 (Fig. 1; 2; 3; 5; 9). To do this, bone fixators 7 are installed in each bone fragment 24, using two crossed needles using a drill. The support 1 is brought to the knitting needles and the knitting needles are fixed to the support 1 with clamps 8. Each spoke is fixed with two clamps 8. First, one end of the spoke is fixed, then the needle is pulled using a tensioner, and the second end of the spoke is fixed. To do this, take the elements 14 and 15 and the groove 16 is laid on the support 1 at the location of the spokes, aligning the holes 17 and pressing the spoke to the element 14. Holding the elements 14 and 15 on the support 1, insert the fastener 9 into the holes 17 with the rod 10, bring the needle into the groove 13 and screw the nut 6 onto the rod 10, pressing the elements 14 and 15 against the support and clamping the spoke between the head 11 and the corrugation 18. The supports 1 mounted on the bone fragments 24 on both sides of the fracture line are connected by four distraction rods 2. For this ends of each distraction about the rod 2 is fixed to the supports 1 with clamps 5. Take the elements 14 and 15 and put the groove 16 on the support 1 at the location of the distraction rod 2, while aligning the holes 17. Holding the elements 14 and 15 on the support 1 into the holes 17 insert the distraction rod 2 screw two nuts 6, pressing elements 14 and 15 to the support. The free end of the distraction rod 2 is likewise fixed to another support 1. The clamps 5 can be installed and together the junction of the two parts 3 and 4 of the support 1. Thus, a rigid system for external fixation of the bone. To create compression, along the fracture line between the bone fragments 24, the nuts 6 located on the distraction rods 2 are rotated so that the supports 1 are approaching. To create a distraction, between the bone fragments 24, the nuts 6 are rotated so that the supports 1 are separated from one another.

AVF can be used in the treatment of fractures and deformities of the limb in children for fixing bone fragments in a given position, creating compression or distraction efforts. At the same time, it provides increased reliability of the fixation of knitting needles (bone fixators 7), due to the use of a bolt-spoke fixator (fastening element 9) with a conical rim 12. The AVF allows you to fix the distraction rods 2 and bone fixators 7 in an arbitrary position on the support 1, which convenient for the surgeon. AVF have a low weight, in comparison with the known analogues, which is ensured by the geometric parameters of the supports 1, their shape and dimensions, as well as the materials used - the supports can be made of titanium alloy. Also, the share of ensuring X-ray transparency, the supports can be made of carbon fiber.

The device can be made on modern industrial equipment from well-known materials and used for its intended purpose in specialized trauma departments of medical institutions.

Claims (18)

1. Children's external fixation device for transosseous osteosynthesis, containing supports, distraction rods for connecting supports, knitting needles, special bolts, clamps for distraction rods or special bolts and nuts for distraction rods and special bolts, characterized in that the supports are transverse the sections are in the form of a hexagon, each clamp consists of two joined elements to cover the support from two opposite sides, each of the joined elements has a groove at one end from the side of the joined side I have a support arrangement, and at the other end has a through hole for a distraction rod or a special fixing bolt, while the axis of the said hole is perpendicular to the axis of the groove, one of the holes of the clamped clamping elements has a chamfer on the non-collapsible side, and when axial elements are joined, the axes of the said holes are aligned and the grooves are located opposite each other, the bolt spoke is made in the form of a rod with a threaded thread and a hexagonal head, the place of transition of the rod into the head is made in the form of a conical rim for distribution position in the said chamfer of the hole of the clamp element, a groove for the spoke is cut out on the conical rim. 2. The apparatus according to claim 1, characterized in that the supports are made of titanium alloy grade VT6. 3. The apparatus according to claim 1, characterized in that the supports are made of aluminum alloy. 4. The apparatus according to claim 1, characterized in that the supports are made of stainless steel. 5. The apparatus according to claim 1, characterized in that the roughness Ra of the outer surfaces is in the range from 0.25 to 0.42 microns. 6. The apparatus according to p. 2 and 3, characterized in that the support has an anodic-oxide protective and decorative coating. 7. The apparatus according to claim 1, characterized in that the distraction rods are made in the form of studs with a metric thread M6 × 1. 8. The apparatus according to claim 1, characterized in that the clamp element of the bone retainer on the outer surface contains corrugation. 9. The apparatus according to claim 1, characterized in that the support is made by a national team, consists of two parts connected end-to-end, so that the interface line forms a step, at the junction of the parts there is a through transverse channel in which the pin is installed. 10. The apparatus according to p. 1, characterized in that the support is made of a national team, consists of two parts connected end-to-end according to the type of "protrusion-groove", so that the interface line forms a step, while the geometric shape of the surface of the protrusion and groove prevents the longitudinal movement of one parts are relatively different. 11. The apparatus according to p. 10, characterized in that the surface of the protrusion and groove contain a persistent flange 12. The apparatus according to p. 10, characterized in that the surface of the protrusion and groove are made with a slope. 13. The apparatus according to claim 1, characterized in that the bone retainers are made in the form of electropolished spokes with a diameter of 1 to 2 mm. 14. The apparatus according to claim 1, characterized in that the supports, distraction rods, clamps, fasteners are made of corrosion-resistant alloy steel. 15. The apparatus according to claim 1, characterized in that the supports, distraction rods, clamps, fasteners are made of titanium alloy VT6. 16. The apparatus according to claim 1, characterized in that the distraction rods and supports are made of a material that is transparent to x-rays. 17. The apparatus according to claim 1, characterized in that the supports in the cross section are in the form of a hexagon, the size is 7 mm. 18. The apparatus according to claim 1, characterized in that the supports are made circular, the inner diameter is in the range from 50 to 240 mm.

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