RU55280U1 - BREAST CLIP DOUBLE-POLE POLYMER - Google Patents

Abstract

The utility model relates to medical equipment and can be used in traumatology and orthopedics to correct the funnel-shaped sternum. The model consists of 2 curved rods located in parallel at a distance of 20 to 30 mm with geometric dimensions: length from 100 to 140 mm, diameter of the circumscribed circle from 4 to 6 mm, having a support plate in the central part with dimensions: length from 30 to 40 mm, width from 55 to 65 mm, thickness from 2 to 5 mm, and rectangular ends at both ends with dimensions: length from 8 to 12 mm, width from 8 to 12 mm, thickness from 2 to 3 mm, while all elements the fixative is made of a copolymer of vinylpyrrolidone with methyl methacrylate, capron fiber and gluconate tsiya.

Description

The utility model relates to medical devices used in traumatology and orthopedics.

Known metal sternum clamp stainless steel, used to correct the funnel-shaped curvature of the sternum. The stainless steel of which the fixer is made is resistant to the action of body fluids, has a specific gravity of ~ 7.0 g / cm ³ and an elastic modulus (stiffness) of 7.5 · 10 ⁵ kg / mm ² , which is an order of magnitude higher than bone stiffness tissue. (Malakhov O.A., Rudakov S.S., Likhotay K.A. Defects in the development of the chest and their treatment. // Bulletin of Traumatology and Orthopedics named after N.N. Priorov, 2002, No. 4, pp. 63-68 )

The use of a metal retainer has a number of disadvantages:

- a second operation is necessary to extract it after the completion of the consolidation processes;

- it is impossible to adjust the size and configuration of the latch during surgery in accordance with the individual characteristics of the patient;

- formation of pressure sores is possible due to the large weight of the fixative and undesirable

tissue reactions to metal;

The technical task of the proposed utility model is to create a sternum fixator from a biodegradable polymer material, which has a low specific gravity and rigidity close to bone stiffness is easily cut with a surgical tool.

The technical result is achieved by the fact that the latch is made in the form of two bent octagonal cross-section rods (1) with a geometric dimension:

diameter described

circumference mm from 4 to 6 length mm from 100 to 140

having in the Central part of the base plate (2) with geometric dimensions:

length mm from 30 to 40 width mm from 55 to 65 thickness mm from 2 to 5

and at both ends are rectangular pads (3) with geometric dimensions:

length mm from 8 to 12 width mm from 8 to 12 thickness mm from 2 to 3

all the details of the fixator are made of a copolymer of vinylpyrrolidone with methyl methacrylate PPM-1, nylon fiber and calcium gluconate in the following ratio of components (% wt.):

Vinylpyrrolidone copolymer

with methyl methacrylate 30.0 - 50.0 Nylon fiber 45.0 - 60.0 Calcium gluconate 5.0 - 10.0

The configuration and geometric dimensions of the individual parts of the latch are determined by the following parameters.

The octagonal section retainer rod provides a larger contact surface with the rib surface compared to a round section rod. In addition, such a rod has a mass less than the mass of a rod of circular cross section, which reduces the time of its biodegradation in the body.

The diameter of the described circumference of the rod is determined by the requirement for its bending strength. The use of a rod with a diameter of less than 4 mm does not provide reliable retention of the sternum in position after correction of curvature. When using rods with a diameter of more than 6 mm, irritation may occur on adjacent tissues.

The length of the shaft is determined by the size of the chest of patients. The operation to correct the funnel-shaped sternum using two-rod clamps is performed for children aged 8 to 14 years. Clamps with rods 100 mm long can be used in patients aged 8 years, with a length of 140 mm - in patients under the age of 14 years.

The size and configuration of the support plate is determined by the size of the body of the sternum of patients aged 8 to 14 years.

The size and configuration of the end pads required to fix the retainer rods to the ribs is determined by the dimensions of the rods themselves and the dimensions of the ribs to which they are attached.

The essence of the utility model is expressed in that all parts of the fixative are made of three components, each of which is able to absorb in the body: PPM-1 copolymer - biodegradation period 1-1.5 years, nylon fiber - 1-1.5 years, calcium gluconate - 4-6 months.

The biodegradation rate is determined by the ratio of components and the size of the implant and is in the range from 1.5 to 3 years.

The ability of the implant to biodegrade in the body environment without toxic effects on the surrounding tissues and on the body as a whole determines the biocompatibility of the fixative.

The utility model is shown in Fig. 1

The latch consists of two bent and parallel rods (1) located in the central part of the base plate (2) and rectangular plates (3) at the ends of the rods

The proposed utility model operates as follows. When correcting the funnel-shaped sternum, the sternum is osteotomy and brought to the correct anatomical position, the central support plate is placed on the sternum body, and the end sections of the rods and end sites are placed on the sternum ribs and the support plate and end areas are fixed using non-absorbable surgical sutures, respectively, to the body and sternal ribs. Then the wound is sutured in layers.

Utility Model Manufacturing Examples

Example No. 1

A prepreg, consisting of 30% copolymer of vnillirrolidone with methyl methacrylate, 60% nylon fiber and 10% calcium gluconate, is placed in 2 molds and, at a temperature of 180 ° C, 2 curved octagonal rods are formed, 100 mm long and 4 mm in diameter, having ends at the ends 2 sites with dimensions: length 8 mm, width 8 mm, thickness 2 mm; two plates with dimensions are formed from a prepreg of the above composition by cold pressing: length 30 mm, width 55 mm, thickness 1 mm. Then between the two plates are placed in the Central part 2 curved

and located at a distance of 20 mm of the rod and by the method of cold pressing 2 plates are pressed into one, at the same time connecting the plate and the rods into a single whole.

Patient K., age 8 years. Funnel chest with curvature angle of 15 °.

A transverse osteotomy was performed and the sternum was corrected to the correct anatomical position.

In the sternum retainer described above, the width of the support plate is reduced to 48 mm with surgical scissors.

The support plate of the fixator described above is applied to the sternum body and the fixation rods are placed on the sternal ribs, and the support plate is fixed with the lavsan suture material to the sternum body, and the rods are attached to the sternum ribs. The wound is sutured in layers. The consolidation time of the sternum and sternum ribs is 3 months. The fixation biodegradation time is 18 months.

Example No. 2

The prepreg, consisting of 40% copolymer of vnylpyrrolidone with methyl methacrylate, 52% capron fiber and 8% calcium gluconate, is placed in 2 molds and, at a temperature of 180 ° C, 2 curved octagonal rods are formed, 120 mm long and 5 mm in diameter, having ends at the ends 2 sites with dimensions: length 10 mm, width 10 mm, thickness 2.5 mm; two plates with dimensions are formed from the prepreg of the above composition by cold pressing: length 35 mm, width 65 mm, thickness 1.5 mm. Then, between the two plates, 2 bent rods are placed in the central part of the rod and parallel to each other at a distance of 25 mm, and 2 plates are pressed by cold pressing into one, simultaneously connecting the plate and the rods into a single unit.

Patient N. Age 10 years. Funnel chest with a curvature angle of 18 °.

A transverse osteotomy was performed and the sternum was corrected to the correct anatomical position.

The support plate of the fixator described above is applied to the sternum body and the fixation rods are placed on the sternal ribs, and the support plate is fixed with the lavsan suture material to the sternum body, and the rods are attached to the sternum ribs. The wound is sutured in layers. The consolidation time of the sternum and sternum ribs is 3 months. The fixation biodegradation time is 27 months.

Example No. 3

A prepreg, consisting of 50% copolymer of vnylpyrrolidone with methyl methacrylate, 45% nylon fiber and 5% calcium gluconate, is placed in 2 molds and, at a temperature of 190 ° C, 2 curved octagonal rods are formed, 140 mm long and 6 mm in diameter, having ends at the ends 2 sites with dimensions: length 12 mm, width 12 mm, thickness 3 mm; two plates with dimensions are formed from a prepreg of the above composition by cold pressing: length 40 mm, width 60 mm, thickness 2.5 mm. Then, between the two plates, two bent rods are placed in the central part of the rod, parallel to each other and located at a distance of 30 mm, and two plates are pressed by cold pressing into one, simultaneously connecting the plate and the rods into a single unit.

Patient B. Age 14 years. Funnel chest with a angle of curvature of 21 °.

A transverse osteotomy was performed and the sternum was corrected to the correct anatomical position.

The support plate of the fixator described above is applied to the sternum body and the fixation rods are placed on the sternal ribs, and the support plate is fixed with the lavsan suture material to the sternum body, and the rods are attached to the sternum ribs. The wound is sutured in layers. The consolidation time of the sternum body and sternal ribs is 3.5 months. The fixation biodegradation time is 36 months.

As can be seen from the data shown in table 1, the application of the proposed utility model allows you to change the dimensions of the latch directly during the operation, eliminates the need for a second operation to remove the latch after completion of the consolidation processes, eliminates the complications associated with an undesirable tissue reaction to the material of the latch. The data presented confirm the achievement of a technical (medical) result.

Comparison of the properties of the sternum retainers according to the proposed utility model and the prototype

Table 1 No.p Name of indicator Parameter value According to the prototype The proposed utility model.
Example one 2 3 one. The specific gravity of the material, g / cm ³ 7.0 1.15 1.16 1.15 2. Modulus of elasticity, MPa 5 · 10 ⁴ 2.7 · 10 ³ 2.8 · 10 ³ 2.8 · 10 ³ 3. The need for the operation to remove the latch after the completion of the consolidation process Yes no no no four. The number of cases of a reaction to a foreign body 8-10 0 0 0 5. The consolidation time of the resected areas of the body and ribs of the sternum, month. four 3 3 3,5 6. Fixer biodegradation time, year Not biodegradable 1,5 2.25 3

Claims (1)

The sternum clamp is made of synthetic material, characterized in that it is made in the form of two curved rods parallel to each other at a distance of 20-30 mm with geometric dimensions: diameter described circumference mm from 4 to 6 length mm from 100 to 140 having rectangular ends with geometric dimensions at the ends: length mm from 8 to 12 width mm from 8 to 12 thickness mm from 2 to 3 and fastened together in the Central part of the base plate with geometric dimensions: length mm from 30 to 40 width mm from 55 to 65 thickness mm from 2 to 5 wherein all the elements of the fixative are made of a copolymer of vinylpyrrolidone with methyl methacrylate PPM-1, nylon fiber and calcium gluconate in the following ratio of components, wt.%: Vinylpyrrolidone copolymer with methyl methacrylate 30.0-50.0 Nylon fiber 45.0-60.0 Calcium gluconate 5.0-10.0