WO2022135008A1

WO2022135008A1 - Minimally invasive minimal stress shielding fracture reduction maintainer

Info

Publication number: WO2022135008A1
Application number: PCT/CN2021/132939
Authority: WO
Inventors: 王永清
Original assignee: 王永清
Priority date: 2020-12-24
Filing date: 2021-11-25
Publication date: 2022-06-30
Also published as: CN112587216A

Abstract

A minimally invasive minimal stress shielding fracture reduction maintainer, which falls under orthopedic medical instruments. The maintainer comprises a cylindrical flexible body portion (1) and helical pieces (2), different pointed portion shapes being provided at two ends of the flexible body portion (1), the helical pieces (2) being inclined helical blades, and a plurality of helical pieces (2) being coaxially arranged on the flexible body portion (1). The flexible body portion (1) is supported in suspension at an axially central position of a medullary cavity, and is not in contact with or fixed to an inner wall of the medullary cavity, causing fatigue resistance thereof to be the strongest, and stress shielding to be the most minimal; and allowing the fracture to be automatically reduced; the flexible body portion (1), a fractured end and a bone callus are subjected to equal stress; when flexible reduction is maintained at equilibrium, the minimally invasive minimal stress shielding fracture reduction maintainer has zero stress shielding, there is no interference in the healing of the fracture, the bone callus of the fractured end can accept pre-fracture original stress stimulation, becoming a force that drives healing of the fracture; gene expression of osteoblasts of the fracture site is triggered, and protein synthesis corresponding to bone formation is accelerated; bone marrow stromal stem cells quickly evolve into osteocytes, proliferate, and ossify, and the bone callus quickly calcifies, consequently promoting the bone fracture to more rapidly heal to an original form and structure of the bone.

Description

Fracture reduction maintainer with minimally invasive and minimal stress shielding

technical field

The invention belongs to an orthopedic medical device, in particular to a minimally invasive and minimally stress shielding fracture reduction maintainer.

Background technique

According to Wolff's law of orthopedic surgery, the growth of bone will be affected by mechanical stimulation and change its structure. It is generally believed that in the early stage of fracture healing, sufficient strength and rigidity are required for fixation. However, due to long-term fixation of steel materials, the bone structure becomes weak and atrophied, and there is a risk of secondary fractures. In the latest domestic edition of "Surgery" textbook and the top domestic monograph "Practical Orthopaedic Science", it is believed that the rotation, bending and shear stress at the fracture end are important factors that affect the smooth growth of bone fracture tissue. Through clinical evidence-based medicine and biomechanical research, we have found for the first time that as long as the fracture end restores its original stress, controllable intermittent rotational, bending and shear stress, like axial stress, is conducive to fracture healing, and at the same time Can speed up fracture healing. That is to say, the original stress on the bone is conducive to fracture healing, and the original stress on the non-skeleton is not conducive to fracture healing. Therefore, we used this discovery for the first time to study its mechanism of action with genetics, and unlocked the secret of the minimally invasive and microstress shielding technology to promote the rapid recovery of fractures.

The initial stage of elastic intramedullary nail is the elastic intramedullary nail with golf club head and polished rod.

In 2000, we developed the clavicle elastic intramedullary nail, the proximal end of which is designed with a positive conical head, followed by a threaded lock higher than the body, which guides the elastic intramedullary nail to walk along the medullary cavity wall and is not easy to pass through the cortical bone; The distal end is an equilateral triangle tip, which is conducive to retrograde penetration of the cortical bone at the distal end of the fracture. Complete intramedullary fixation, minimally invasive or closed surgery, prevents screw retraction and promotes early fracture healing to a certain extent, but has no anti-fracture shortening function.

In 2016, the above clavicle elastic intramedullary nail was improved, and an elastic interlocking intramedullary nail was designed. The proximal end is a right conical head, followed by a threaded lock that is higher than the body; the distal end is a regular triangle tip, which is conducive to retrograde. It penetrates the cortical bone at the distal end of the fracture; there is a thread lock in the middle that is higher than the body, and its thread pitch is different from that of the tip thread; two thread locks cross the fracture end to maintain the stability of the bone length and the broken end. Complete intramedullary fixation, minimally invasive or closed surgery, prevents withdrawal, can stretch and compress the fractured end, and promote fracture healing to a certain extent.

However, although this elastic interlocking intramedullary nail is fixed in the intramedullary cavity, due to its elasticity, it will elastically deform in the medullary cavity according to the shape of the medullary cavity, and the intramedullary nail will have a wider contact with the inner wall of the medullary cavity for fixation. , instead of the true intramedullary axial fixation, resulting in the dislocation of the fracture end and the poor automatic reduction effect of the fracture. In this way, the elastic interlocking intramedullary nail and the fracture end both receive uneven stress, so the fatigue resistance of the intramedullary nail is If it is weakened, it is easy to lead to broken nails and interfere with the healing of fractures to a certain extent. In addition, the effect of automatic reduction of fractures is not good, and steel wires or ropes are needed to assist in the fixation to achieve the reduction of the fractured end, which will cause unfavorable stress and damage to the fractured end, affecting the normal healing of the fracture.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the above-mentioned defects, and to provide a minimally invasive and microstress shielding fracture reduction maintainer, the body of which is not fixed in contact with the inner wall of the medullary cavity, and the body is suspended and supported at the axial position of the medullary cavity, thus resisting Compared with the previous intramedullary nails, the fracture can be automatically reduced; the body, fracture end and callus receive equal stress; when the force of elastic strain is balanced, the fracture can be shielded by minimally invasive and microstress The stress shielding of the reduction maintainer is zero, the fracture healing is not disturbed, and the fractured end can receive the original stress stimulation before fracture, which becomes the driving force for fracture healing; the genes of osteoblasts at the fracture site are strongly expressed, and the corresponding proteins of bone formation are stimulated. The synthesis is accelerated, the bone marrow stromal stem cells rapidly evolve into bone cells, proliferate, ossify and rapidly calcify the callus, which in turn promotes the accelerated healing of fractures to their original shape and structure. This is an important result of a series of numerous clinical evidence-based medicine, biomechanics and molecular biology researches that I have experienced for 26 years. The minimally invasive and minimally stress-shielded fracture reduction maintainer has achieved gratifying achievements in rapid recovery in clinical fracture treatment.

The object of the present invention is achieved by the following technical solutions: a minimally invasive and minimal stress shielding fracture reduction maintainer, which comprises an elastic body part, the elastic body part is cylindrical, and both ends are provided with pointed parts of different shapes, which It is characterized in that: it also includes a helical sheet, the helical sheet is a helical blade with a complete height, and a plurality of helical sheets are coaxially arranged on the elastic body part.

The elastic body part is made of 317L stainless steel or titanium alloy or nickel-titanium alloy material.

The diameter of the elastic body portion is 1-8 mm.

The axial width of the helical sheet on the elastic body portion is 0.4-12 mm.

The distance from the blade root where the helical sheet is connected with the elastic body part to the blade edge is 0.5-8 mm.

The width of the root connecting the helical sheet and the elastic body is 0.5-5mm.

The inclination angle of the helical sheet and the axis of the elastic body part is 10-70 degrees.

2-20 helical sheets are coaxially arranged on the elastic body part, and can form a helical sheet group.

The tip may be a conical tip, a pyramid tip, a triangular blade tip, and a triangular tip.

The advantages and beneficial effects of the present invention are:

1. From the perspective of the suspension fixation principle, the minimally invasive microstress shielding fracture reduction maintainer is a minimally invasive reduction and intramedullary suspension segmented elastic locking, which is a true axial maintenance reduction. According to the needs of reducing the fracture site, the number, position, width, inclination angle and height of the helical slices are designed. The blade of the helical slice is in cutting contact with the inner wall of the medullary canal, and the body is suspended and supported at the axial position of the medullary canal. It is in contact with the inner wall of the marrow cavity, but the axis is in a suspended state. Such a minimally invasive and microstress shielding fracture reduction maintainer has the strongest fatigue resistance, prevents nails from breaking, and minimizes stress shielding, so that the callus at the broken end of the fracture during the healing process. Accepting uniform stress stimulation can promote the rapid healing of fractures. Therefore, the minimally invasive and microstress shielding fracture reduction maintainer can automatically reduce the fracture and make the fracture healing effect better.

2. From the perspective of biomechanics, the minimally invasive microstress shielding fracture reduction maintainer is in the medullary cavity, and the body will produce elastic deformation with the movement of the fracture end, and the stress shielding force will increase. At this time, the elastic strain force of the body Play the role of anti-fracture fracture. When the elastic strain force of the body and the interaction force of the muscles and ligaments around the fracture are in a balanced and static state, the minimally invasive micro-stress shielding fracture reduction maintainer has zero stress shielding at the fracture end, and the zero stress shielding makes the bones originally endured. Stress recovery, the motivation and ideal mechanical environment to promote and accelerate the rapid healing of fractures.

Zero stress shielding enables the fractured end to reproduce the original stress stimulation before fracture, that is, what kind of stress the bone originally received, and what kind of stress stimulation is required in the process of fracture healing. The magnitude of the force is the stress at the fracture end during painless functional training, and the stress at this time becomes the "power" for fracture healing.

3. From the point of view of molecular biology, the external causes of things work through internal causes. In fracture healing, the smaller the stress shielding, the better the effect of stress recovery stimulation. Stress stimulation promotes fracture healing. A series of osteogenic intrinsic factors, that is, the up- and down-regulated expression of related genes, produce osteogenic proteins of different magnitudes, which play a role in promoting and accelerating fracture healing. The minimally invasive and microstress shielding fracture reduction maintainer restores the original bone stress after the fracture is reduced, which triggers the strong gene expression of osteoblasts in the callus at the fracture site, and causes the bone marrow stromal stem cells in the callus to rapidly evolve and proliferate into osteocytes. , ossification and rapid calcification of callus, promote and accelerate the synthesis of the corresponding protein in bone formation, and then promote fracture healing to its original shape and structure, and accelerate fracture healing.

4. The minimally invasive and minimally stress-shielded fracture reduction maintainer can minimally reduce and elastically fix all tubular and non-tubular fractures of the clavicle, humerus, ulna and radius, palmar phalanx, femur, tibia, fibula, patella, and metatarsal phalanx.

5. The closed reduction method, elastic reduction and maintenance method, fracture healing time, mechanics and molecular biological mechanism of the minimally invasive microstress shielding fracture reduction maintainer are the same as those of the traditional Chinese splint technique, but the fixation position is different. The minimally invasive microstress shielding fracture reduction and maintenance The device is in the medulla, and the TCM splint technique is in vitro.

In conclusion, the minimally invasive and microstress shielding fracture reduction maintainer brings theoretical support from mechanics, molecular biology and clinical evidence-based medicine.

Description of drawings

Figure 1 is a schematic structural diagram of the present invention.

FIG. 2 is a partial enlarged view of FIG. 1 .

Figure 3 is the X-ray film of the minimally invasive and minimally stress-shielded fracture reduction maintainer for clavicle fractures.

Figure 4 is the X-ray film of the fracture reduction maintainer with minimally invasive and minimal stress shielding for fractures of the femur, tibia and humerus.

Figure 5 is the X-ray film of the fracture reduction maintainer with minimally invasive and microstress shielding for the fracture of the palmar phalanx and the metatarsophalangeal bone.

in:

1-Elastomer part, 2-Spiral piece, 3-Head, 4-Tail.

Detailed ways

Example: As shown in Figures 1 and 2, a minimally invasive and minimally stress shielding fracture reduction maintainer includes an elastic body part 1, and the elastic body part can be made of 317L stainless steel or titanium alloy or nickel-titanium alloy. The body portion 1 is cylindrical, with a diameter of 1-12 mm. The two ends of the elastic body portion 1 are fractured according to different fixed parts, and are provided with a tip portion 3 of different shapes, and the tip portion can be a circular cone tip or/and a pyramid tip. , triangular blade, the spiral piece is used to guide the elastic body part 1 to crawl with the inner wall of the medullary cavity; the minimally invasive and minimal stress shielding fracture reduction maintainer also includes 2-20 spiral pieces 2 arranged on the elastic body part 1 at coaxial intervals , the helical blade 2 is a helical blade with a complete height, the blade width is the axial width of the blade on the elastic body part is 0.4-12mm, the blade height is the distance between the blade root part where the blade and the elastic body part are connected to the blade edge part The thickness of the blade, that is, the thickness of the root connecting the blade and the elastic body part, is 0.5-5 mm; the inclination angle between the spiral sheet 2 and the axis of the elastic body part is 10-70 degrees.

As shown in Figure 3, taking the reduction of the clavicle as an example, it belongs to the fracture of the irregular bone fixed by elastic strain. The elastic body part 1 is 150-260mm long and 1.5-4.0mm in diameter. The front part is a regular cone or a right pyramid, the purpose is to control the minimally invasive and microstress shielding fracture reduction maintainer not easily penetrate the cortical bone; It is easy to penetrate the cortical bone; from the proximal end of the elastic body part 1, a spiral piece 2 is set at an interval of 10-50mm, and there are 6-9 pieces in total. The width of each spiral piece 2 is the axial width on the elastic body part. 1.4-3.0mm, the thickness of each helix 2, that is, the thickness of the root connected to the elastic body part is 0.5-1.5mm, and the height of each helix 2, that is, the distance from the root of the blade connected to the elastic body to the blade edge is 0.5-2.5mm, the inclination angle of each spiral piece 2 and the axis of the elastic body part 1 is 20-60 degrees. During reset, the spiral piece 2 leads the elastic body 1 to crawl with the inner wall of the intramedullary cavity to the distal end, and the elastic body 1 undergoes elastic deformation changes in the intramedullary cavity, which is consistent with the shape of the intramedullary cavity, and the spiral piece 2 attaches the elastic body to the inner wall of the intramedullary cavity. The part 1 is suspended in the axial position of the medullary cavity of the clavicle, and each helical piece 2 is closely tangent to the inner wall of the medullary cavity, and the clavicle is fixed in sections, and the fracture will be automatically reduced, which brings a good maintenance reduction effect. Because the elastic body part 1 is suspended from the axis of the bone marrow cavity, a reasonable elastic biomechanical fixation is obtained, and the high expression of various genes of osteogenic proteins is induced, resulting in a good molecular biological therapeutic effect-rapid fracture healing, that is, Fractures recover quickly.

As shown in Figure 4, taking the fixation of the femur, tibia, and humerus as examples, it belongs to the fracture of the large tubular bone with elastic reduction. The elastic body part 1 is 240-480mm long and 3.0-8.0mm in diameter. The tip parts 3 at both ends are the head and the tail respectively. The head is a regular triangular pyramid and the tail is a triangular prism. , the tail part is connected with the power drill; the tail part 4 of the elastic body part 1 is coaxially provided with 6 spiral pieces 2, and each spiral piece 2 is arranged at an interval of 5-20mm; ; Between the head and the tail of the elastic body part 1, one helical sheet 2 is set at an interval of 20-50 mm, and a total of 6 are arranged; the width of each helical sheet 2, that is, the axial width on the elastic body part is 3-20 mm , the height of each helical blade 2, that is, the distance from the blade root connected to the elastic body to the blade edge is 4.0-6.0mm, and the thickness of each helical blade 2, that is, the thickness of the root connecting the blade to the elastic body is 1.5-5mm , the inclination angle of each spiral piece 2 and the axis of the elastic body part 1 is 40-60 degrees. When maintaining the reduction, the elastic body portion 1 is suspended at the axial position of the bone marrow cavity of fractures such as the femur, the tibia, and the humerus, respectively. The spiral blade edge is closely tangent to the inner wall of the bone marrow cavity such as the femur, tibia, and humerus, and is locked and fixed in sections, and the fracture will be automatically reduced, which brings a good maintenance reduction effect. Because the elastic body part 1 is suspended from the axis of the bone marrow cavity, reasonable elastic biomechanical fixation is obtained, high expression of various genes of osteogenic proteins is induced, and a good molecular biological therapeutic effect is produced—rapid fracture healing.

As shown in Figure 5, taking the fixation of palm bone and phalanx fractures as an example, it belongs to the elastic fixation of small tubular bone fractures. The elastic body part 1 is 8-15mm long and 1.0-2.0mm in diameter. The tip parts 3 at both ends are the head and the tail respectively. The head and tail are both regular triangular pyramids. The proximal end of the body 1, that is, the head 3, is provided with a spiral piece 2 coaxially, and a spiral piece 2 is arranged at an interval of 5-20 mm from the spiral piece 2, and 4-10 spiral pieces 2 can be arranged. The width, that is, the axial width on the elastic body part, is 0.5-1.5 mm. The thickness of the blade, that is, the thickness of the root connecting the blade and the elastic body part, is 0.5-1.5 mm, and the inclination angle between each spiral piece 2 and the axis of the elastic body part 1 is 20-60 degrees. When maintaining the reduction, the elastic body part 1 is suspended at the axial position of the medullary cavity of the palmar bone and the phalangeal fracture, respectively. The spiral blade is cut and fixed with the inner wall of the medullary cavity of the palm and phalanx, and the palm, phalanx, metatarsal, and phalanges of the foot are locked and fixed in sections, and the fracture will automatically reduce, which brings a good maintenance reduction effect. Because the elastic body part 1 is suspended from the axis of the bone marrow cavity, reasonable elastic biomechanical fixation is obtained, high expression of various genes of osteogenic proteins is induced, and a good molecular biological therapeutic effect is produced—rapid fracture healing.

Claims

A minimally invasive and microstress shielding fracture reduction maintainer, comprising an elastic body part, the elastic body part is cylindrical, and both ends are provided with tips of different shapes, and is characterized in that: it further comprises a helical sheet, the helical sheet is For a helical blade with a full height, a plurality of helical blades are coaxially arranged on the elastic body part.
The minimally invasive and minimally stress shielding fracture reduction maintainer according to claim 1, wherein the elastic body part is made of 317L stainless steel or titanium alloy or nickel-titanium alloy material.
The minimally invasive and microstress shielded fracture reduction maintainer according to claim 1, wherein the diameter of the elastic body portion is 1-8 mm.
The minimally invasive and minimally stress shielding fracture reduction maintainer according to claim 1, wherein the axial width of the helical sheet on the elastic body portion is 0.4-12 mm.
The minimally invasive and minimally stress shielding fracture reduction maintainer according to claim 1, wherein the distance from the blade root connecting the helical sheet and the elastic body to the blade edge is 0.5-8 mm.
The minimally invasive and minimally stress shielding fracture reduction maintainer according to claim 1, wherein the width of the root connecting the helical sheet and the elastic body portion is 0.5-5 mm.
The minimally invasive and minimally stress shielded fracture reduction maintainer according to claim 1, wherein the inclination angle between the helical sheet and the axis of the elastic body is 10-70 degrees.
The minimally invasive and microstress shielding fracture reduction maintainer according to claim 1, wherein 2-20 helical sheets are coaxially arranged on the elastic body portion, and can be formed into a helical sheet group.
The minimally invasive and minimally stress shielding fracture reduction maintainer according to claim 1, wherein the tip portion can be a conical tip portion, a pyramid tip portion, a flat triangular blade, a triangular prism and a spherical shape.