A stress-reducing, shrouded, biomimetic multilayer radius bone plate

Abstract

A biomimetic multilayer radial bone plate with reduced stress shielding, belonging to the field of medical device technology, includes a base plate and a sandwich layer. The base plate consists of a distal radius fixation plate and a radial fixation plate, which are integral structures. The radial fixation plate has a hollow structure, and the sandwich layer fills the hollow part of the radial fixation plate. The sandwich layer consists of several three-dimensional diagonal cross structural units and several screw hole bases. The three-dimensional diagonal cross structural units are based on deep-sea glass sponge, evolving its two-dimensional double diagonal structure into three-dimensional independent three-dimensional diagonal cross structural units. The novel three-dimensional diagonal cross structural units not only have excellent compressive and torsional resistance, but also have more uniform stress distribution than the original structure, ensuring structural strength. By combining the bone plate with the novel three-dimensional diagonal cross structural units, the mechanical properties of the bone plate are taken into account while effectively reducing the stiffness of the bone plate, reducing stress shielding, and preventing complications such as secondary fractures and osteoporosis.

Description

[0001] This invention belongs to the field of medical device technology, and specifically relates to a biomimetic multilayer radial bone plate that reduces stress shielding. Background Technology

[0002] With the increasing aging of the global population, rapid economic development, and the promotion of sports, the incidence of distal radius fractures is increasing year by year. Statistics show that distal radius fractures are among the most common fractures in the human body, accounting for three-quarters of forearm fractures and one-fifth of all fracture patients. Survey data indicates that the number of people aged 65 and above in my country has now exceeded 200 million, and this number is expected to continue to grow rapidly in the future. Distal radius fractures have become an urgent public health problem that needs to be addressed.

[0003] Depending on the location and severity of the fracture, current treatment methods for distal radius fractures mainly include closed reduction, external fixation with plaster casts or splints, external fixation with external fixators, internal fixation with Kirschner wires, internal fixation with locking plate systems, internal fixation with intramedullary nails, distal radius hemiarthroplasty, or bone graft replacement. Among these, internal fixation with plate systems is currently the most commonly used method in clinical treatment of distal radius fractures.

[0004] The primary function of bone plates is to connect and fix the bone fragments in a fracture, maintaining their reduced position, and then, combined with rehabilitation training, restoring normal motor function. Literature review indicates that current bone plates are mainly made of stainless steel, cobalt alloys, and titanium alloys, but their stiffness is far greater than that of human bone. This leads to stress shielding, resulting in insufficient stress stimulation at the fracture site during the healing process, often causing secondary fractures and osteoporosis in the later stages of recovery. To address this problem, researchers have begun to modify the materials and structure of bone plates to reduce the stiffness of the material, thereby reducing stress shielding. For example, researchers have used polymers such as polylactic acid (PLLA), high-density polyethylene (HDPE), and polyvinyl ether ketone (PEEK) as bone plate materials. These materials have an elastic modulus similar to that of human bone and good biocompatibility, reducing stress shielding to some extent. However, studies have found that these polymer bone plates generally have poor mechanical properties, frequently resulting in fractures and bending. In addition, researchers have also improved stress shielding by modifying the structure of the bone plate, mainly by reducing the cross-sectional area and thickness, and by using corrugated designs and adding holes to the bone plate to reduce its stiffness. These design schemes have a certain effect on reducing stress shielding, but the effect is still not significant and further improvements are urgently needed.

[0005] Glass sponges live year-round in the deep sea, enduring the constant impact of seawater without structural damage. Biomaterial mechanics studies have shown that their double-diagonal surface structure exhibits lightweight, high strength, and high torsional resistance, demonstrating excellent structural strength for the same material dosage. Researchers attempted to simplify this structure for use in bone plate design to reduce stress shielding. However, mechanical analysis revealed that due to the simplified two-dimensional structure of the glass sponge, the stress distribution is uneven, posing a risk of fracture failure.

[0006] In summary, there is an urgent need to develop a radial bone plate that can effectively reduce stress shielding and meet mechanical performance requirements. Summary of the Invention

[0007] The purpose of this invention is to reduce stress shielding in the radial fracture area, and to provide a biomimetic multilayer radial bone plate that reduces stress shielding.

[0008] A biomimetic multilayer radial bone plate for reducing stress shielding includes a base plate and a sandwich layer. The base plate is composed of a distal radius fixation plate and a radial fixation plate, which are integral structures with an included angle θ1 of 160°-170° between them. The radial fixation plate is a hollow structure, and the sandwich layer fills the hollow portion of the radial fixation plate. The sandwich structure consists of several three-dimensional diagonal intersecting structural units and several screw hole bases. The several three-dimensional diagonal intersecting structural units are evenly arranged in a single layer and surround the screw hole bases. The three-dimensional diagonal cross structure unit is based on deep-sea glass sponge. Its two-dimensional double diagonal structure is evolved into a three-dimensional independent three-dimensional diagonal cross structure unit. The unit is externally a cube frame with a side length of 0.9-1.1mm. Inside, there are four pairs of diagonally cross beams. The starting and ending points of all beams are located at one-third of the frame side length away from the vertex. It presents a stable symmetrical double diagonal structure on its front and side. The screw hole base is provided with interlayer screw holes; The distal radius fixation plate has several distal radius screw holes, and the radial fixation plate and the interlayer have several radial screw holes. Several fan-shaped notches are evenly distributed on both sides of the back of the radial fixation plate. The angle θ2 of each fan-shaped notch is 100°-110° and the radius R is 5-7mm. The radial screw holes and the intercalation screw holes are equal in number and their positions correspond to each other.

[0009] The distal radius fixation plate has several grooves, and a unit block composed of three-dimensional diagonal cross structure units is fixedly installed in the grooves.

[0010] The distal radius screw hole is equipped with a corresponding distal radius screw, and the radial screw hole is equipped with a corresponding radial screw.

[0011] One of the radial screw holes is an elongated screw hole.

[0012] The distal radius screw holes are seven in number.

[0013] The radial screw holes are five in number.

[0014] The distal radius screw hole and the radial screw hole are equipped with a corresponding number of screws.

[0015] Both the substrate and the interlayer are made of titanium alloy.

[0016] The substrate and the interlayer are both manufactured as a single unit using 3D printing. The working process and working principle of this invention: Based on the annular double-layer double-diagonal physical structure of deep-sea glass sponge, this invention evolves and optimizes a novel three-dimensional diagonal cross structure unit. The novel three-dimensional diagonal cross structure unit not only has excellent compressive and torsional resistance, but also has a more uniform stress distribution than the original structure, thus ensuring structural strength.

[0017] The process of using this invention is as follows: 1. Fix the patient with a distal radius fracture on the operating table and use a palmar approach to open the fracture with a scalpel.

[0018] 2. After the radial flexor carpi radialis and the radial artery are fully exposed, insert a Kirschner wire into the radial carpi radialis joint. Sections are temporarily fixed.

[0019] 3. The fractured bone fragments are manually reduced, and the area is retracted before the bone plate is implanted. The device is opened to make the field of vision clear.

[0020] 4. Implant the distal radius bone plate and initially fix it with Kirschner wires and one screw, then proceed with transdermal fixation. Observe the fracture reduction and the position of the bone plate to see if they are correct, and then make adjustments accordingly.

[0021] 5. Remove the Kirschner wires and implant the remaining screw assembly into the body. After rinsing, perform layer-by-layer suturing.

[0022] The beneficial effects of this invention are: 1. Based on the physical structure of deep-sea glass sponge with a ring-shaped double layer and double diagonal, this invention evolves and optimizes a novel three-dimensional diagonal cross structure unit. The novel three-dimensional diagonal cross structure unit not only has excellent compressive and torsional resistance, but also has a more uniform stress distribution than the original structure, thus ensuring structural strength.

[0023] 2. By combining the bone plate with the novel three-dimensional diagonal cross structure unit, the mechanical properties of the bone plate are taken into account, while the stiffness of the bone plate is effectively reduced, stress shielding is reduced, and complications such as secondary fractures and osteoporosis are prevented.

[0024] 3. Several fan-shaped notches are evenly distributed on the back of the radial fixation plate, which can reduce the contact area between the plate and the bone surface, promote blood circulation, and accelerate recovery.

[0025] 4. Several grooves are provided on the distal radius fixation plate, and unit blocks composed of three-dimensional diagonal cross structure units are fixed in the grooves, which can reduce stress shielding of the distal radius. Attached Figure Description

[0026] Figure 1 This is a three-dimensional schematic diagram of an embodiment of the present invention.

[0027] Figure 2 This is a side view of an embodiment of the present invention.

[0028] Figure 3 This is a front view of the substrate according to an embodiment of the present invention.

[0029] Figure 4 This is a three-dimensional schematic diagram of the interlayer according to an embodiment of the present invention.

[0030] Figure 5 This is a front view of the interlayer in an embodiment of the present invention.

[0031] Figure 6 This is a three-dimensional schematic diagram of a novel three-dimensional diagonal cross structure unit according to an embodiment of the present invention.

[0032] Figure 7 This is a front view of a novel three-dimensional diagonal cross structure unit according to an embodiment of the present invention.

[0033] Figure 8 This is a side view of a novel three-dimensional diagonal cross structure unit according to an embodiment of the present invention. Detailed Implementation

[0034] Please see Figures 1 to 8 The image shown is an embodiment of the present invention.

[0035] A biomimetic multilayer radial bone plate for reducing stress shielding includes a base plate 1 and a sandwich layer 2. The base plate 1 is composed of a distal radius fixation plate 11 and a radial fixation plate 12, which are integral structures with an included angle θ1 of 165° between them. The radial fixation plate 12 is a hollow structure, and the sandwich layer 2 fills the hollow part of the radial fixation plate 12. The interlayer 2 is composed of three-dimensional diagonal cross structure units 3 and five screw hole bases 21. The three-dimensional diagonal cross structure units 3 are arranged uniformly in a single layer and surround the screw hole bases 21. The three-dimensional diagonal cross structure unit 3 is based on the deep-sea glass sponge. Its two-dimensional double diagonal structure is evolved into a three-dimensional independent three-dimensional diagonal cross structure unit. The unit is external to a cube frame 31 with a side length of 1.0 mm. Inside, there are four pairs of diagonally cross beams 32. The starting point and ending point of all beams 32 are located at one-third of the frame side length away from the vertex. It presents a stable symmetrical double diagonal structure on its front and side. The screw hole base 21 is provided with a sandwich screw hole 211; The distal radius fixation plate 11 has seven distal radius screw holes 111, the radial fixation plate 12 and the interlayer 2 have five radial screw holes 121, and ten fan-shaped notches 122 are evenly distributed on both sides of the back of the radial fixation plate 12. The angle θ2 of each fan-shaped notch 122 is 105° and the radius R is 6mm. The radial screw holes 121 and the intercalation screw holes 211 are equal in number and their positions correspond to each other.

[0036] The distal radius fixation plate 11 has four grooves, and a unit block 13 composed of three-dimensional diagonal cross structure units is fixedly installed in the grooves.

[0037] The distal radius screw hole 111 is equipped with a corresponding distal radius screw 4, and the radial screw hole 121 is equipped with a corresponding radial screw 5.

[0038] One of the radial screw holes 121 is an elongated screw hole.

[0039] The distal radius screw hole 111 and the radius screw hole 121 are equipped with a corresponding number of screws.

[0040] The substrate 1 and the interlayer 2 are made of titanium alloy, specifically Ti-6Al-4V.

[0041] The substrate 1 and the interlayer 2 are manufactured as a single unit by 3D printing.

[0042] The working process and working principle of this invention embodiment: Based on the annular double-layer double-diagonal physical structure of deep-sea glass sponge, this embodiment evolves and optimizes a novel three-dimensional diagonal cross structure unit. The novel three-dimensional diagonal cross structure unit not only has excellent compressive and torsional resistance, but also has a more uniform stress distribution than the original structure, thus ensuring structural strength.

[0043] The usage process of this embodiment is as follows: 1. Fix the patient with a distal radius fracture on the operating table and use a palmar approach to open the fracture with a scalpel.

[0044] 2. After the radial flexor carpi radialis and the radial artery are fully exposed, insert a Kirschner wire into the radial carpi radialis joint. Sections are temporarily fixed.

[0045] 3. The fractured bone fragments are manually reduced, and the area is retracted before the bone plate is implanted. The device is opened to make the field of vision clear.

[0046] 4. Implant the distal radius bone plate and initially fix it with Kirschner wires and one screw, then proceed with transdermal fixation. Observe the fracture reduction and the position of the bone plate to see if they are correct, and then make adjustments accordingly.

[0047] 5. Remove the Kirschner wires and implant the remaining screw assembly into the body. After rinsing, perform layer-by-layer suturing.

Claims

1. A biomimetic multilayer radial bone plate for reducing stress shielding, characterized in that: The device includes a base plate (1) and a sandwich layer (2). The base plate (1) is composed of a distal radius fixation plate (11) and a radius fixation plate (12). The distal radius fixation plate (11) and the radius fixation plate (12) are integral structures, and the included angle θ1 between them is 160°-170°. The radius fixation plate (12) is a hollow structure, and the sandwich layer (2) is filled in the hollow part of the radius fixation plate (12). The sandwich layer (2) consists of several three-dimensional diagonal cross structure units (3) and several screw hole bases (21). The several three-dimensional diagonal cross structure units (3) are arranged uniformly in a single layer and surround the screw hole bases (21). The three-dimensional diagonal cross structure unit (3) is based on deep-sea glass sponge. Its two-dimensional double diagonal structure is evolved into a three-dimensional independent three-dimensional diagonal cross structure unit. The unit is external to a cube frame (31). The side length of the cube frame (31) is 0.9-1.1mm. There are four pairs of diagonally cross beams (32) inside. The starting point and ending point of all beams (32) are located at one-third of the frame side length away from the vertex. The starting point is the four vertices of a face, and the ending point of each starting point is the opposite vertex of the diagonal of the body where the starting point is located. It presents a stable symmetrical double diagonal structure on its front and side. The screw hole base (21) is provided with a sandwich screw hole (211); The distal radius fixation plate (11) is provided with several distal radius screw holes (111), the radial fixation plate (12) and the interlayer (2) are provided with several radial screw holes (121), and several fan-shaped notches (122) are evenly distributed on both sides of the back of the radial fixation plate (12). The angle θ2 of each fan-shaped notch (122) is 100°-110° and the radius R is 5-7mm. The radial screw hole (121) and the intercalation screw hole (211) are equal in number and their positions correspond to each other.

2. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: The distal radius fixation plate (11) has several grooves, and a unit block (13) composed of three-dimensional diagonal cross structure units is fixedly installed in the grooves.

3. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: The distal radius screw hole (111) is equipped with a corresponding distal radius screw (4), and the radial screw hole (121) is equipped with a corresponding radial screw (5).

4. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: One of the radial screw holes (121) is an elongated screw hole.

5. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: The distal radius screw holes (111) are seven in number.

6. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: The radial screw hole (121) is five in number.

7. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: The distal radius screw hole (111) and the radius screw hole (121) are equipped with a corresponding number of screws.

8. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: The substrate (1) and the interlayer (2) are made of titanium alloy.

9. The biomimetic multilayer radial bone plate for reducing stress shielding according to claim 1, characterized in that: The substrate (1) and the interlayer (2) are manufactured as a single unit by 3D printing.

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