Metatarsal bone fusion nail

Abstract

The utility model belongs to the technical field of medical instruments, and discloses a metatarsal bone fusion nail. The metatarsal bone fusion nail comprises a bone nail body and a cross nail, one end of the bone nail body is a screwing-in part used for being screwed into a metatarsal bone, the other end of the bone nail body is a fixing part, a matching hole and an injection hole are formed in the fixing part, the injection hole is used for injecting bone cement, and the cross nail is used for fixing the bone nail body. An injection flow channel communicated with the injection hole is formed in the bone nail main body, and an overflow port communicated with the injection flow channel is formed in at least the screwing-in part of the bone nail main body; the cross nail is arranged in the matching hole in a penetrating mode and used for being connected with the metatarsal bone or the tarsal bone. The metatarsal fusion nail can solve the problems that a bone nail is weak in pull-out resistance and prone to displacement, complications are caused, and the risk of a secondary operation is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, in particular to a metatarsal fusion nail. Background Art

[0002] In the field of orthopedics, metatarsal fusion is a common surgical procedure used to treat metatarsal-related diseases. When a metatarsal bone is broken, deformed, or otherwise severely injured, a metatarsal osteotomy is necessary to restore the function and stability of the bone.

[0003] One end of the traditional metatarsal bone screw is screwed into the patient's metatarsal through a thread, and the other end is clamped in the metatarsal or tarsal by an elastic clip at the clamping part. Although this type of bone screw can be integrated into the metatarsal, its ability to resist pullout is relatively weak. As time passes after surgery or the patient exercises vigorously, it is easy to cause the bone screw to shift, which may cause complications such as postoperative floating toe, metatarsal head malformation and changes in the distal joint surface, increasing the risk of secondary surgery. Utility Model Content

[0004] The utility model aims to provide a metatarsal fusion nail, which can solve the problems of weak anti-pullout ability of bone nails, easy displacement leading to complications and increased risk of secondary surgery.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A metatarsal fusion nail, comprising:

[0007] A bone screw body, one end of which is a screw-in portion, which is used to be screwed into a metatarsal bone, the other end of which is a fixing portion, which is provided with a matching hole and an injection hole, which is used to inject bone cement, an injection channel connected to the injection hole is provided in the bone screw body, and an overflow port connected to the injection channel is provided on at least the screw-in portion of the bone screw body;

[0008] A cross nail is inserted into the matching hole and is used to connect with the metatarsal bone or tarsal bone.

[0009] As an optional solution of the above-mentioned metatarsal fusion nail, the injection hole is provided at one end of the fixing portion along the axial direction of the bone nail body away from the screw-in portion.

[0010] As an optional solution of the above-mentioned metatarsal fusion nail, the screw-in portion includes spirally extending screw teeth, and the overflow port is located between two adjacent circles of the screw teeth.

[0011] As an optional solution of the above-mentioned metatarsal fusion nail, at least two overflow ports are provided on the screw-in portion.

[0012] As an optional solution of the above-mentioned metatarsal fusion nail, at least two of the overflow ports are staggered along the circumference of the screw-in portion.

[0013] As an optional solution for the above-mentioned metatarsal fusion nail, the bone nail body includes a head, a connecting rod segment and a threaded rod segment, the head forms the fixing portion, the threaded rod segment forms the screw-in portion, and the threaded rod segment and the connecting rod segment are both provided with the overflow port.

[0014] As an optional solution of the above-mentioned metatarsal fusion nail, the matching hole includes a pressurizing section, and the top end of the cross nail abuts against the pressurizing section to press the fixing part toward the metatarsal or tarsal.

[0015] As an optional solution of the above-mentioned metatarsal fusion nail, the end of the screw-in portion away from the fixing portion is a pointed end, and a self-tapping groove is provided on the pointed end.

[0016] As an optional solution of the above-mentioned metatarsal fusion nail, the bone nail body and the cross nail are made of titanium alloy.

[0017] As an optional solution of the above-mentioned metatarsal fusion nail, the bone nail body and the cross nail are vertically arranged.

[0018] Beneficial effects of the utility model:

[0019] In the metatarsal fusion nail provided by the utility model, one end of the bone nail body is fixed to the metatarsal by being screwed into the metatarsal, and the other end can be fixed by cooperating with the cross nail and abutting against the metatarsal or tarsal under the action of the cross nail; at the same time, bone cement can be injected into the bone nail body through the injection hole, and the bone cement flows to the overflow port through the injection flow channel. After overflowing from the overflow port, the affected metatarsal and the bone nail body can be connected by the solidification of the bone cement. In this fixing method, both ends of the bone nail body are firmly fixed, and the bone cement is connected to the affected metatarsal, so that the fixation of the bone nail body is more firm, and the anti-pullout ability of the bone nail body can be improved, thereby avoiding displacement after surgery, which is conducive to the healing of the affected part and the elimination of complications, and reducing the risk of secondary surgery.

[0020] In addition, bone cement can also adjust the average density of the metatarsal fusion nail and bone cement, so that the density of the affected area is close to the bone density, improving the postoperative effect. It is understandable that by adjusting the injection amount of bone cement, a more precise fixation effect can be obtained, and the average density of the metatarsal fusion nail and bone cement can also be controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of the metatarsal fusion nail provided by the utility model when it is not assembled;

[0022] Figure 2The utility model is a schematic diagram of the structure of the metatarsal fusion nail.

[0023] In the figure:

[0024] 10. Bone screw body; 11. Threaded rod section; 111. Overflow port; 112. Self-tapping groove; 12. Head; 121. Matching hole; 122. Injection hole; 13. Connecting rod section; 20. Cross nail. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0026] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0028] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0029] like Figure 1 and Figure 2As shown, this embodiment provides a metatarsal fusion nail, including a bone nail body 10 and a cross nail 20. One end of the bone nail body 10 is a screw-in portion, which is used to be screwed into the metatarsal bone, and the other end of the bone nail body 10 is a fixing portion, which is provided with a matching hole 121 and an injection hole 122, and the injection hole 122 is used to inject bone cement, and an injection channel connected to the injection hole 122 is provided in the bone nail body 10, and at least the screw-in portion of the bone nail body 10 is provided with an overflow port 111 connected to the injection channel; the cross nail 20 is inserted into the matching hole 121, and the cross nail 20 is used to connect with the metatarsal bone or the tarsal bone.

[0030] Both the bone screw body 10 and the cross nail 20 can be screwed into the metatarsal bone. One end of the bone screw body 10 is fixed to the metatarsal bone by screwing into the metatarsal bone, and the other end can be fixed by cooperating with the cross nail 20 and abutting against the metatarsal bone or tarsal bone under the action of the cross nail 20. At the same time, bone cement can be injected into the bone screw body 10 through the injection hole 122, and the bone cement flows to the overflow port 111 through the injection flow channel. After overflowing from the overflow port 111, the affected metatarsal bone and the bone screw body 10 can be connected by the solidification of the bone cement. In this fixing method, both ends of the bone screw body 10 are firmly fixed and connected to the affected metatarsal bone with the help of the bone cement. The fixation of the bone screw body 10 is more firm, which can improve the anti-pullout ability of the bone screw body 10, thereby avoiding displacement after surgery, facilitating the healing of the affected part and eliminating complications, and reducing the risk of secondary surgery.

[0031] In addition, bone cement can also adjust the average density of the metatarsal fusion nail and bone cement, so that the density of the affected area is close to the bone density, improving the postoperative effect. It is understandable that by adjusting the injection amount of bone cement, a more precise fixation effect can be obtained, and the average density of the metatarsal fusion nail and bone cement can also be controlled.

[0032] In this embodiment, the cross nail 20 and the bone screw body 10 are cross-arranged so that the direction of the force applied by the cross nail 20 to the bone screw body 10 intersects with the direction in which the bone screw body 10 is rotated into the metatarsal bone. The bone screw body 10 is subject to resistance in two intersecting directions when it is pulled out, that is, the direction of the force applied by the cross nail 20 to the bone screw body 10 intersects with the direction in which the bone screw body 10 rotates and moves to pull out, which can improve the anti-pullout ability of the bone screw body 10.

[0033] Optionally, the bone screw body 10 and the cross nail 20 can be arranged vertically. In other embodiments, the angle between the cross nail 20 and the bone screw body 10 can also be an acute angle.

[0034] In order to facilitate the injection of bone cement, the injection hole 122 is provided on the fixing part, and at least a part of the surface of the fixing part is exposed outside the metatarsal bone, so as to facilitate the exposure of the injection hole 122 and facilitate the injection of bone cement into the bone screw body 10 through the injection hole 122. Preferably, the injection hole 122 is provided at an end of the fixing part away from the screw-in part, so that the injected bone cement can fully flow along the length direction of the bone screw body 10 to overflow at the overflow port 111.

[0035] Optionally, the injection hole 122 may be a circular hole. In other embodiments, the injection hole 122 may also be other shapes, such as an elliptical hole, or other polygonal holes such as a square hole, a triangle hole, etc.

[0036] In order to improve the fixation effect of the bone cement on the bone screw body 10 and the affected part after solidification, the screw-in portion includes a spirally extending screw thread, and the overflow port 111 is located between two adjacent circles of screw threads. This arrangement can provide space for the overflow of bone cement, making it convenient for the bone cement to contact the affected part after overflowing.

[0037] Optionally, at least two overflow ports 111 may be provided to increase the overflow position of bone cement, increase the contact surface between bone cement and the outer surface of the bone screw body 10 and the affected part, increase the overflow amount of bone cement, and improve the fixation effect.

[0038] In this embodiment, every two circles of screw threads form a group, and at least one overflow port 111 is provided between two adjacent circles of screw threads in each group to increase the overflow position of bone cement and improve the fixation effect.

[0039] Optionally, among all the overflow openings 111 on the screw-in portion, at least two overflow openings 111 are staggered along the axial direction of the screw-in portion. This arrangement can increase the overflow direction of bone cement, thereby improving the fixing effect between the bone screw body 10 and the affected part.

[0040] In this embodiment, the bone screw body 10 is a screw structure, so as to be screwed into the metatarsal of the affected part. Specifically, the bone screw body 10 includes a head 12, a connecting rod section 13 and a threaded rod section 11. The head 12 forms a fixing part, the threaded rod section 11 forms a screwing part, and the threaded rod section 11 is provided with threads so that the bone screw body 10 can be fixed in the metatarsal by rotation.

[0041] By providing the connecting rod segment 13 , the connection between the threaded rod segment 11 and the head 12 can be evenly transitioned, thereby avoiding interference between the cross nail 20 and the threads on the threaded rod segment 11 .

[0042] In order to improve the fixing effect, overflow ports 111 are provided on the threaded rod section 11 and the connecting rod section 13 .

[0043] Optionally, the diameter or cross-sectional area of ​​the connecting rod segment 13 is smaller than the diameter or cross-sectional area of ​​the head 12, and is also smaller than the outer diameter of the threaded rod segment 11, so that the bone cement overflowing from the overflow port 111 on the connecting rod segment 13 can play a limiting role after solidification, thereby preventing the bone screw body 10 from moving in the direction of increasing or decreasing the depth of screwing into the metatarsal bone, thereby improving the fixation effect of the bone screw body 10.

[0044] Optionally, the area of ​​the overflow port 111 on the connecting rod segment 13 can be larger than the area of ​​the overflow port 111 on the threaded rod segment 11. The connecting rod segment 13 has no threads and does not need to avoid threads. The area of ​​the overflow port 111 can be increased to facilitate the overflow of bone cement and fill the gap between the bone screw body 10 and the affected area.

[0045] In this embodiment, the positional relationship between the overflow port 111 and the injection hole 122 allows the bone cement to be evenly injected into the affected area, and the injection speed and pressure can be freely adjusted, making the injection of bone cement more convenient and accurate, which helps to improve the healing effect of the fracture and the patient's recovery.

[0046] In order to improve the fixing effect of the cross nail 20 on the bone screw body 10, the matching hole 121 includes a pressurizing section. After the bottom end of the cross nail 20 passes through the matching hole 121, the top end of the cross nail 20 can abut against the pressurizing section. Through the squeezing of the cross nail 20 and the bone screw body 10, the metatarsal bone connected to the bone screw body 10 and the metatarsal bone or tarsal bone connected to the cross nail 20 are made to contact more closely, thereby achieving better and better effects.

[0047] Optionally, the pressure section can be adjusted in shape and size so that there is a squeezing force between the cross nail 20 and the pressure section when they are matched, thereby improving the healing effect. Optionally, the shape of the pressure section can be the same as the shape of the top of the cross nail 20, but the size of the pressure section is slightly smaller than the size of the top of the cross nail 20 to achieve a squeezing effect. Alternatively, the inner wall of the pressure section can be provided with continuous or discontinuous protrusions, which abut against the cross nail 20 to provide squeezing force; or the pressure section can be a tapered hole, so that the cross nail 20 forms a line contact or point contact with the tapered hole to improve the squeezing effect.

[0048] In the present embodiment, the cross nail 20 is a screw, preferably, the cross nail 20 is a self-tapping screw, to facilitate connection with the metatarsal or tarsal. In other embodiments, the cross nail 20 can also be a pin.

[0049] To facilitate the screwing section to be screwed into the metatarsal bone, the end of the screwing section away from the fixing section is a tip, and a self-tapping groove 112 is provided on the tip, so that the threaded rod section 11 is a self-tapping screw structure. Optionally, the number of self-tapping grooves 112 can be the same as the number of threads on the threaded rod section 11.

[0050] In this embodiment, the bone screw body 10 and the cross nail 20 are made of titanium alloy. Titanium alloy has high strength, so that the bone screw body 10 and the cross nail 20 have sufficient rigidity and stability.

[0051] In this embodiment, by injecting bone cement into the bone screw body 10, the average density of the bone cement, the bone screw body 10 and the cross nail 20 can be close to the bone density, thereby solving the complications of floating toe and malformation of metatarsal head caused by fixation by metal bone screws in the prior art. In this embodiment, the bone cement can also better fix the metatarsal bones, effectively avoiding the occurrence of the above complications.

[0052] By adjusting the amount of bone cement injected and the position of the overflow port 111, a more precise fixation effect can be achieved, which helps to eliminate problems such as metatarsal head malformation and distal joint surface changes, thereby improving the success rate of the operation.

[0053] The metatarsal fusion nail provided in this embodiment is suitable for linear and parallel shortening osteotomy of smaller metatarsals. Compared with traditional replacement osteotomy, it has less trauma and recovery period, is more suitable for some patients, and has a wide range of uses.

[0054] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A metatarsal fusion nail, characterized in that: include: A bone screw body (10), one end of the bone screw body (10) is a screw-in portion, the screw-in portion is used to be screwed into the metatarsal bone, the other end of the bone screw body (10) is a fixing portion, the fixing portion is provided with a matching hole (121) and an injection hole (122), the injection hole (122) is used to inject bone cement, an injection channel connected to the injection hole (122) is provided in the bone screw body (10), and at least the screw-in portion of the bone screw body (10) is provided with an overflow port (111) connected to the injection channel; A cross nail (20), wherein the cross nail (20) is inserted into the matching hole (121), and the cross nail (20) is used to connect with the metatarsal bone or the tarsal bone.

2. The metatarsal fusion nail according to claim 1, characterized in that: The injection hole (122) is provided at one end of the fixing portion axially away from the screw-in portion along the bone screw body (10).

3. The metatarsal fusion nail according to claim 1, characterized in that: The screw-in portion comprises a spirally extending screw thread, and the overflow port (111) is located between two adjacent circles of the screw thread.

4. The metatarsal fusion nail according to claim 1, characterized in that: At least two overflow ports (111) are arranged on the screw-in portion.

5. The metatarsal fusion nail according to claim 4, characterized in that: At least two overflow ports (111) are staggeredly arranged along the circumference of the screw-in portion.

6. The metatarsal fusion nail according to any one of claims 1 to 5, characterized in that: The bone screw body (10) comprises a head (12), a connecting rod section (13) and a threaded rod section (11); the head (12) forms the fixing portion, the threaded rod section (11) forms the screw-in portion, and both the threaded rod section (11) and the connecting rod section (13) are provided with the overflow port (111).

7. The metatarsal fusion nail according to any one of claims 1 to 5, characterized in that: The matching hole (121) comprises a pressurizing section, and the top end of the cross nail (20) abuts against the pressurizing section to press the fixing portion toward the metatarsal bone or tarsal bone.

8. The metatarsal fusion nail according to any one of claims 1 to 5, characterized in that: An end of the screw-in portion away from the fixing portion is a tip, and a self-tapping groove (112) is provided on the tip.

9. The metatarsal fusion nail according to any one of claims 1 to 5, characterized in that: The bone nail body (10) and the cross nail (20) are made of titanium alloy.

10. The metatarsal fusion nail according to any one of claims 1 to 5, characterized in that: The bone nail body (10) and the cross nail (20) are arranged vertically.

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