RU201274U1 - DAMPER FOR EXTERNAL FIXING DEVICE ON FOOT - Google Patents

Abstract

The technical solution relates to medical technology, namely to devices used in traumatology and orthopedics in devices for external fixation of bones. The device is used in the treatment of patients with diabetic Charcot osteoarthropathy in the conditions of using the method of transosseous osteosynthesis to create conditions of directional elasticity at the junction of the fusion bones of the arthrodesic foot joint. The damper device for the external fixation device on the foot (Fig. 5; 6; 7) steel or titanium alloy) threaded rod 1, with nuts 2. The screw thread is made with metric thread M6x1. Nuts 2 hexagon wrench, 10mm. Elastic elements 3 are installed between the nuts 2 to be placed on the threaded rod 1 from two opposite sides of the support 4 of the apparatus. Each elastic element 3 is located between two washers 5. One washer 5 is intended for contact with the nut 2, the second washer 5 is intended for contact with the support 4 of the apparatus. The technical result consists in creating a device for the apparatus for external fixation of the foot, providing mutual elastic-elastic micro-motion of the supports feet and leg supports. The device provides a stable "springy" fixation, in which the stability of the apparatus structure is not allowed to be disturbed and the controlled mobility of the bones is provided. 8 p.p. f-ly, 7 ill.

Description

The technical solution relates to medical technology, namely to devices used in traumatology and orthopedics in devices for external fixation of bones. The device is used in the treatment of patients with Charcot's diabetic osteoarthropathy in the conditions of using the method of transosseous osteosynthesis to create conditions for directional elasticity at the junction of the fusion bones of the arthrodesic foot joint.

To fix the bones of the hindfoot in the known external fixation devices, open supports made in the form of a ring, with one row of fixing holes are widely used. Semicircular supports made in the form of a ½ ring are also used, while to increase the area for fixing the spokes, they are built up with the help of attachment strips, or an additional commensurate half-ring is introduced. The supports are rigidly connected to each other by threaded rods with nuts or rods.

The known apparatus of G.A. Ilizarov for transosseous osteosynthesis (copyright certificate SU 1055499). The device contains supports in the form of flat half-rings (arcs, annular sectors) and rings with spokes mounted on them, connected by threaded rods with nuts and forming blocks for fixing the proximal and distal bone fragments. The device is equipped with distractors, hinge assemblies, assemblies for adjusting and fixing the position of supports and spokes. There are sets of parts for G.A. Ilizarov for operations on the foot and lower leg (source: electronic catalog of products of the Federal State Unitary Enterprise "Experimental Plant of the Russian Research Center" VTO "named after Academician G.A. Ilizarov of the Ministry of Health of Russia, posted on the company's website http://www.ozrncvto.ru, in the section “Products” subsections “Instruments and devices for transosseous osteosynthesis according to GA Ilizarov”, “Sets of parts for the Ilizarov apparatus.” Access mode http://www.ozrncvto.ru/blank-sto5i). Supports on the foot are connected to the base of the device on the lower leg, i.e. with supports installed on the lower leg, threaded rods with nuts. Supports on the shins with supports on the foot are rigidly connected, clamping the support between the nuts on a threaded rod. The 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 rods-screws installed on them, connected by distraction rods (threaded rods, telescopic rods) and forming blocks of fixation and reduction. Spokes and rods are screws, fixed on the supports. The supports are made with through holes evenly spaced in one row, the longitudinal axes of the holes are located radially symmetrically to the longitudinal axis of the ring, while the supports in the form of half rings contain bends and can be connected so that they form a ring, a part of the ring. From the described parts, the supports of the foot apparatus are assembled with one row of fixing holes and consisting of 2 half rings. At the same time, one half-ring is used to fix the spokes held in the back of the foot. Often, to fix the needles on the foot with a large cross, the half-ring support is built up with the help of extension bars, or an additional commensurate half-ring is introduced.

In external foot fixation devices manufactured by Orthofix (Orthofix electronic catalog, 2019, p. 15, access mode: https://www.orthofix.com/wp-content/uploads/2019/01/PM_010_E0.pdf), and Smith & nephew ( Smith & Nephew electronic catalog, Foot Rings, Pre-Assembled Foot and Ankle Frames p. 2.15, accessed https://www.smith-nephew.com/global/assets/pdf/products/surgical/tsf-iliz -hardware-pocket-ref-guide-05052.pdf) use foot supports designed to fix the entire foot, without the possibility of resizing the inner contour, this is a monolithic support for fixing the entire foot. The foot support is rigidly connected to the base leg supports. The foot support allows you to fix the needles passed through different parts of the foot at the same time, and given the presence of several rows of fastening holes, it is possible to install additional modules and articulated joints in the required plane. Despite all the positive aspects in the use of monolithic supports, there are a number of disadvantages: the cumbersome structure, the lack of adjustment of the size of the inner contour, the impossibility of eliminating individual components of the foot deformation. Supports on the foot are connected to the base of the apparatus on the lower leg, with threaded rods with nuts. The supports are connected rigidly by clamping them between the nuts on a threaded rod.

In the described devices, the connection of the support on the foot with the base of the apparatus on the lower leg, supports on the lower legs, is performed rigidly by means of metal threaded rods with nuts, by tightening the nuts, this allows to ensure the rigidity of the device, but does not allow providing conditions for directional elasticity of the device at the fusion joint of the arthrodesis joint feet. Movement (micromobility) is a prerequisite for successful arthrodesis; for this, nuts are loosened in known devices, but this leads to instability of the device structure. The support on the foot does not have the ability to move relative to the support on the lower leg, so at the points of connection with the threaded rods, the nuts snuggle the support tightly and do not contain elastic elements between the support and the nut,

Known apparatus for eliminating foot deformation (patent RU 2732) containing annular leg supports and two arched supports of the calcaneus and metatarsal bones, interconnected by threaded rods with hinge nodes, spokes and elements for their fixation. The support of the metatarsal bones is connected to a threaded rod connecting the leg supports, a multi-plane movement unit and is equipped with an additional unit containing two brackets on which threaded rods with heads are fixed, hinged to each other, and on one of the rods a sleeve is fixed, to the ends of which the spokes are attached with emphasis.

The supports are rigidly clamped between the nuts on the threaded rods. The device does not allow creating conditions for directional elasticity of the device at the fusion joint of the arthrodesisable foot joint.

Thus, the problem of known external fixation devices for osteosynthesis of the bones of the foot is that they do not provide conditions for directional elasticity of the device at the junction of the fused bones, since they do not contain systems that provide elastic-elastic mutual micromobility of the foot support and the leg support.

The task of the utility model is to ensure the elasticity of the apparatus at the junction of the fused bones.

The technical result consists in creating a device for an apparatus for external fixation of the foot, which provides mutual elastic-elastic micromovement of the foot supports and leg supports. The device provides a stable "springy" fixation, in which the stability of the apparatus structure is not allowed to be disturbed and the controlled mobility of the bones is provided.

The technical result is achieved in that the damper device for the external fixation device on the foot contains a threaded rod, with nuts, elastic elements are installed between the nuts, designed to be placed on the threaded rod from two opposite sides of the device support, each elastic element is located between two washers, one washer is intended for contact with the nut, the second washer is intended for contact with the device support.

It is envisaged that the elastic element is made in the form of a metal compression spring.

It is envisaged that the device contains two elastic elements made in the form of metal compression springs.

It is envisaged that the elastic element is made in the form of an elastic-elastic polymeric flattened sleeve.

It is envisaged that the device contains two elastic elements made in the form of elastic-elastic polymeric flattened bushings.

It is provided that the device contains two elastic elements, one is made in the form of a metal compression spring, the second is made in the form of an elastic-elastic polymer flattened sleeve.

It is envisaged that the device contains four elastic elements, two are made in the form of a metal compression spring, two are made in the form of an elastic-elastic polymeric flattened sleeve.

It is envisaged that the washers are flat or concave round (in the shape of a bowl).

A damper device for an external fixation device on the foot (hereinafter referred to as the device) is illustrated by graphic materials:

Figure 1 - details of the device;

Fig. 2 is a general view of the device (example No. 1), two elastic elements are made in the form of a metal compression spring, the washers are made flat;

Figure 3 is a general view of the device (example No. 2), two elastic elements made in the form of elastic-elastic polymer flattened bushings, one washer is made concave, the other is flat;

Fig. 4 - General view of the device (example No. 3), two elastic elements, one is made in the form of a metal compression spring, the second is made in the form of an elastic-elastic polymer flattened sleeve;

Fig. 5 is a general view of the device (example No. 4), four elastic elements, two are made in the form of a metal compression spring, two are made in the form of an elastic-elastic polymer flattened sleeve.

Fig. 6 is a side view of the external fixation device, the device is installed between the supports;

Fig. 7 is a front view of the external fixation device, the device is installed between the supports.

On graphic materials, numbers indicate:

1 - threaded rod;

2 - nut;

3 - elastic element: 3- compression spring, 3b- elastic-elastic polymeric flattened bushing;

4- apparatus;

5 - washer: 5 - flat washer; 5b-bowl-shaped washer.

Implementation of the device.

A damper device for an external fixation device on the foot is used for arthrodesis of the joints of the foot, in the treatment of patients with diabetic Charcot's osteoarthropathy, in the elimination of deformities of various origins, replacement of defects, elongation, treatment of bone fractures, by means of transosseous osteosynthesis.

General description of the device. The damper device for the external fixation device on the foot (Fig. 1; 6; 7) contains a metal (stainless steel or titanium alloy) threaded rod 1, with nuts 2. The screw thread is made with metric thread M6x1. Nuts 2 hexagon wrench, 10mm. Elastic elements 3 are installed between the nuts 2, intended to be placed on the threaded rod 1 from two opposite sides of the support 4 of the apparatus. Each elastic element 3 is located between two washers 5. One washer 5 is designed to contact the nut 2, the second washer 5 is designed to contact the support 4 of the apparatus.

Private example No. 1 (figure 2; 6; 7). The damper device for the external fixation device on the foot contains a metal threaded steel rod 1, with metal nuts 2, M6x1 thread. Nuts 2 hexagon wrench, 10mm. Elastic elements 3 are installed between the nuts 2, intended to be placed on the threaded rod 1 from two opposite sides of the support 4 of the apparatus. The elastic elements 3 are made in the form of two metal compression springs 3a. Each compression spring 3a is located between two flat washers 5a. One washer 5a is designed to contact the nut 2, the second washer 5a is designed to contact the support 4 of the apparatus. Compression springs 3a when installing the device on support 4 are compressed by nuts 2 from opposite sides of support 4. Washers 5a with an outer diameter of 9 mm. Springs 3a with an inner diameter of 7 mm perform the function of an elastic insert, provide and damp vibrations of the supports 4 of the apparatus.

Private example No. 2 (Fig. 3; 6; 7). The damper device for the external fixation device on the foot contains a metal threaded steel rod 1, with metal nuts 2, M6x1 thread. Nuts 2 hexagon wrench, 10mm. Elastic elements 3 are installed between the nuts 2, intended to be placed on the threaded rod 1 from two opposite sides of the support 4 of the apparatus. Elastic elements 3 are made in the form of two elastic-elastic polymer flattened bushings 3b, rounded. Each elastic-elastic polymer flattened bushing 3b is located between two washers 5. One flat washer 5a is intended for contact with the support 4, the second concave washer 5b, in the shape of a bowl, is intended for contact with the nut 2. The elastic-elastic polymer flattened bushing 3b is laid in washer 5a, when the device is installed on the support 4, the bushings 3b are tightened with nuts 2 on opposite sides of the support 4. Washers 5a and 5b have an outer diameter of 20mm. Bushings 3b perform the function of an elastic insert, provide and damp vibrations of the supports 4 of the apparatus.

Private example No. 3 (Fig. 4; 6; 7). The damper device for the external fixation device on the foot contains a metal threaded steel rod 1, with metal nuts 2, M6x1 thread. Nuts 2 hexagon wrench, 10mm. Two elastic elements 3 are installed between the nuts 2, intended to be placed on the threaded rod 1 from two opposite sides of the support 4 of the apparatus. One elastic element 3 is made in the form of a metal compression spring 3a, the second elastic element 3 is made in the form of an elastic-elastic polymeric flattened sleeve 3b. The compression spring 3a is located between two flat washers 5a with an outer diameter of 9mm. One washer 5a is designed to contact the nut 2, the second washer 5a is designed to contact the support 4 of the apparatus. An elastic-elastic polymer flattened sleeve 3b is located between two washers 5a with an outer diameter of 20 mm. One flat washer 5a is intended for contact with the support 4, the second flat washer 5b is intended for contact with the nut 2. Elastic elements 3 when installing the device on the support 4 are tightened by nuts 2 from opposite sides of the support 4. Elastic elements 3 perform the function of an elastic insert, provide and damp vibrations of the supports 4 of the apparatus.

Private example No. 4 (Fig. 5; 6; 7). The damper device for the external fixation device on the foot contains a metal threaded steel rod 1, with metal nuts 2, M6x1 thread. Nuts 2 hexagon wrench, 10mm. Elastic elements 3 are installed between the nuts 2, intended to be placed on the threaded rod 1 from two opposite sides of the support 4 of the apparatus. Four elastic elements 3 are located on the threaded rod, two are made in the form of a metal compression spring 3a, two are made in the form of an elastic-elastic polymer flattened sleeve 3b. Each compression spring 3a is located between two flat washers 5a with an outer diameter of 9mm. One washer 5a is designed to contact the nut 2, the second washer 5a is designed to contact the support 4 of the apparatus. Compression springs 3a when the device is installed on the support 4 are compressed by nuts 2 from opposite sides of the support 4. The springs 3a with an inner diameter of 7 mm perform the function of an elastic insert, provide and damp the vibrations of the support 4 of the apparatus. Each resiliently elastic polymeric flattened bushing 3b is located between two washers 5 with an outer diameter of 20 mm. One flat washer 5a is intended for contact with support 4, the second concave washer 5b, in the shape of a bowl, is intended for contact with nut 2. Elastic-elastic polymer flattened bushing 3b is placed in washer 5a, when the device is installed on support 4, bushings 3b are tightened by nuts 2 from opposite sides of the support 4. Bushings 3b perform the function of an elastic insert, provide and damp the vibrations of the support 4 of the apparatus.

The apparatus for fixing the parts of the foot is an external semi-circular support (Fig. 6; 7), which ensures stable retention and / or and dosed movement of one (distal) bone fragment or limb segment relative to another (proximal) bone fragment or limb segment in different planes. In this case, the movement of the distal bone fragment or segment of the limb along the length and axis is performed by tightening the nuts on the longitudinal threaded rod, and in width - on the transverse threaded rod. In addition, the support allows you to firmly fix in the required plane the needles drawn through the bone with a tensile force of 130 kgf and more.

The device for fixing the parts of the foot (Fig. 6; 7) with a damper device allows you to adapt the dimensions of the inner contour of the support under the foot of the operated patient, freely fix the spokes drawn through the various parts of the foot and establish articulated joints, reposition nodes, taking into account the existing deformations, without loss rigidity of the structure.

Using the device.

A damper device for an external fixation device on the foot is used to connect the supports 4 of the device (Fig. 6,7). The device allows to create conditions for directional elasticity of the apparatus at the fusion joint of the arthrodesic foot joint.

For example 1; 2; 3. On the threaded rod 1, set the first nut 2, the first washer 5, the first elastic element 3, the second washer 5, the free end of the threaded rod 1 is inserted into the hole of the first support 4, the third washer 5 is put on the free end of the threaded rod 1, the second elastic element 3 , the fourth washer 5, the second nut 2 is screwed on, the first and the second nuts 2 are tightened, the support 4 is clamped on the threaded rod 1. The second support is fixed to the remaining free end of the threaded rod 1 by means of nuts. Thus, two supports 4 (on the lower leg and foot) are connected by a threaded rod 1, so that one support installed between the elastic elements 3 has the ability, under the action of a load, to perform micromotions, oscillate in a range limited in volume, the range of motion is limited by the stiffness of elastic elements 3 and the force of tightening the nuts 2. Elastic-elastic mutual micromovement of the foot supports and the shin support is provided.

For example 4. On the threaded rod 1, install the first nut 2, the first washer 5, the first elastic element 3, the second washer 5, the free end of the threaded rod 1 is inserted into the hole of the first support 4, the third washer 5 is put on the free end of the threaded rod 1, the second elastic element 3, the fourth washer 5, screw on the second nut 2, tighten the first and second nuts 2, clamp the support 4 on the threaded rod 1. On the threaded rod 1 from the other end, install the third nut 2, the fifth washer 5, the third elastic element 3, the sixth washer 5, the free end of the threaded rod 1 is inserted into the hole of the second support 4, the seventh washer 5 is put on the free end of the threaded rod 1, the fourth elastic element 3, the eighth washer 5, the fourth nut 2 is screwed on, the third and fourth nuts 2 are tightened, the support 4 is clamped on threaded rod 1. Thus, two supports 4 (on the lower leg and foot) are connected by a threaded rod 1, so that both supports 4 (on the lower leg and foot) installed between the elastic elements 3 have the ability, under the action of a load, to make micromotions, to oscillate in a limited volume range, the range of movements is limited by the stiffness of the elastic elements 3 and the tightening force of the nuts 2. Elastic-elastic mutual micromovement of the foot supports and the leg support is provided.

Thus, the device solves the problem of known external fixation devices for osteosynthesis of the bones of the foot, provides the conditions for directional elasticity of the device at the junction of the fusion bones. The device provides a stable "springy" fixation, in which the stability of the structure of the apparatus is not allowed and controlled mobility of bones is ensured, in the range limited by the stiffness of elastic elements and the force of tightening the nuts.

Claims (9)

1. A damper device for an external fixation device on the foot, containing a threaded rod with nuts, characterized in that elastic elements are installed between the nuts, intended to be placed on the threaded rod from two opposite sides of the apparatus support, each elastic element is located between two washers, one washer is intended for contact with the nut, the second washer is intended for contact with the device support. 2. A damper device for an external fixation device on the foot according to claim 1, characterized in that the elastic element is made in the form of a metal compression spring. 3. A damper device for an external fixation device on the foot according to claim 1, characterized in that it contains two elastic elements made in the form of metal compression springs. 4. A damper device for an external fixation device on the foot according to claim 1, characterized in that the elastic element is made in the form of an elastic-elastic polymeric flattened sleeve. 5. A damper device for an external fixation device on the foot according to claim 1, characterized in that the device contains two elastic elements made in the form of elastic-elastic polymeric flattened bushings. 6. A damper device for an external fixation device on the foot according to claim 1, characterized in that the device contains two elastic elements, one is made in the form of a metal compression spring, the second is made in the form of an elastic-elastic polymer flattened sleeve. 7. A damper device for an external fixation device on the foot according to claim 1, characterized in that the device contains four elastic elements, two are made in the form of a metal compression spring, two are made in the form of an elastic-elastic polymer flattened sleeve. 8. A damper device for an external fixation device on the foot according to claim 1, characterized in that the washers are flat. 9. A damper device for an external fixation device on the foot according to claim 1, characterized in that the washers are made concave, rounded, in the shape of a bowl.

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