CN111631788A - A bio-enhanced intramedullary nail - Google Patents

Abstract

The invention discloses a biologically enhanced intramedullary nail, which comprises a main nail, a head nail and an injection device; the main nail is arranged along the length direction of the femur, and the main nail consists of a proximal part, a transition part and a distal part composition; the proximal part is provided with a fixing hole, which is inclined and arranged through the proximal part, and the head nail passes through the fixing hole and is arranged in the femur; the inner parts of the main nail and the head nail A communicating fluid hole is provided, and the injection device is connected with the fluid hole inside the head nail to inject fluid into the inner cavity of the femur via the head nail and the main nail. The bio-enhanced intramedullary nail provided by the present invention has a reasonable structure, and fluid holes are arranged inside the main nail and the head nail so as to inject bio-enhanced hydrogel, which not only satisfies the mechanical enhancement function of fracture fixation, but also realizes the regeneration effect. The biological enhancement function regulated by the microenvironment can solve the technical problems of malunion, insufficient mechanical properties of the healing site, and even nonunion.

Description

A bio-enhanced intramedullary nail

technical field

The invention relates to the technical field of medical devices, in particular to a biologically enhanced intramedullary nail.

Background technique

The current clinical fracture treatment concepts include the strong fixation concept and the biological fixation concept. The strong fixation concept only considers the mechanical properties and fails to take into account the regulation and enhancement of the biological microenvironment. Compared with the strong fixation concept method, the biological fixation concept method is composed of Mechanics has been transformed into biology, which better protects blood supply and reduces the interference to the local bone biological microenvironment, but it still cannot completely solve the problem of regeneration and repair caused by the destruction of the biological environment after fracture. For example, for intramedullary nails, this symmetrical central splint fixation method may cause malunion caused by displacement of the broken ends, insufficient mechanical properties of the healing site, and even nonunion.

Patent CN111012463A discloses an intramedullary nail system for the treatment of proximal femoral fractures, which includes a main nail, a head nail and a support nail. The main nail is composed of a proximal part, a transition part and a distal part. Passing through the head nail hole located in the proximal part, the support nail passes through the support nail hole located in the transition part, and the end of the support nail abuts the underside of the head nail; the main nail, the head nail and the support nail are in the femur. The proximal end forms a triangular structure. This patent belongs to a strong fixed concept, which fails to take into account the regulation and enhancement of the biological microenvironment.

Therefore, there is an urgent need to design a biologically enhanced intramedullary nail, which takes into account the regulation and enhancement of the biological microenvironment and solves the technical problems existing in the prior art.

SUMMARY OF THE INVENTION

The purpose of the present invention is to address the above technical problems. The present invention provides a bio-enhanced intramedullary nail with a reasonable structure. Fluid holes are arranged inside the main nail and the head nail to inject bio-enhanced hydrogel, which not only satisfies the The mechanical enhancement function of fracture fixation also realizes the biological enhancement function of the regulation of the regenerative microenvironment, and solves the technical problems of malunion, insufficient mechanical properties of the healing site, and even nonunion.

In order to solve the above technical problems, the present invention provides a bio-enhanced intramedullary nail, including a main nail, a head nail and an injection device; the main nail is arranged along the length direction of the femur, and the main nail consists of a proximal part, a transition part and a distal part; the proximal part is provided with a fixing hole, which is inclined and arranged through the proximal part, the head nail passes through the fixing hole and is set in the femur; the main nail and the The interior of the head nail is provided with a communicating fluid hole, and the injection device is connected with the fluid hole inside the head nail, so as to inject fluid into the inner cavity of the femur through the head nail and the main nail.

In some embodiments, a main nail channel is provided inside the main nail, which extends downward along the length direction of the main nail and is located at the lower part of the fixing hole.

In some embodiments, a stud channel and a vertical channel are provided inside the stud, the stud channel is arranged along a length direction of the stud, and the vertical channel is along a radial direction of the stud. The vertical hole is arranged and communicated with the vertical hole, and the vertical hole is communicated with the fluid hole of the main nail.

In some embodiments, a limiting groove is provided on the outer peripheral side of the head nail, and the limiting groove is arranged opposite to the vertical hole.

In some embodiments, the main nail is further provided with a circumferential hole, and the circumferential hole is arranged along the radial direction of the main nail and communicates with the main nail hole.

In some embodiments, the fluid injected by the injection device is a bio-enhanced hydrogel.

In some embodiments, the outer end of the stud is provided with a connecting portion, and the connecting portion is arranged coaxially with the hole of the stud.

In some embodiments, the injection device is connected to the stud hole through an adapter and a pipeline, and the adapter is sealedly connected to the connection portion.

In some embodiments, the outer end of the head nail is further provided with a tightening portion, which is rotated into the fixing hole of the proximal end portion.

In some embodiments, the circumferential bore is located at the distal end portion of the main tack and has an inner diameter no greater than the inner diameter of the main tack bore.

Beneficial effects of the present invention:

The bio-enhanced intramedullary nail provided by the present invention has a reasonable structure. Fluid holes are arranged inside the main nail and the head nail so as to inject bio-enhanced hydrogel, which not only satisfies the mechanical enhancement function of fracture fixation, but also realizes the The biological enhancement function of the regulation of the regenerative microenvironment can solve the technical problems of malunion, insufficient mechanical properties of the healing site, and even nonunion.

Description of drawings

The above-mentioned advantages of the present invention will become clearer and easier to understand from the detailed description in conjunction with the following drawings, which are only schematic and do not limit the present invention, wherein:

1 is a schematic structural diagram of a biologically enhanced intramedullary nail according to the present invention;

Fig. 2 is the disassembled view of the components of the bio-enhanced intramedullary nail described in Fig. 1;

Figure 3 is a sectional view of the main nail of the present invention;

Fig. 4 is the structural representation of the head nail of the present invention;

Figure 5 is a cross-sectional view of the head nail of the present invention;

Fig. 6 is the structural schematic diagram of the injection device of the present invention;

7 is a schematic diagram of an application example of the bio-enhanced intramedullary nail according to the present invention;

FIG. 8 is a schematic diagram of a static torque testing device.

In the picture:

10. Main nail; 11. Proximal part; 12. Transition part; 13. Distal part; 14. Fixing hole; 15. Main nail hole; 16. Circumferential hole;

20. Head nail; 20a. Connection part; 20b. Tightening part; 21. Head nail hole; 22. Vertical hole; 23. Limit groove;

30. Injection device; 31. Adapter.

Detailed ways

The bio-enhanced intramedullary nail described in the present application will be described in detail below with reference to specific embodiments and accompanying drawings.

The embodiments described herein are specific embodiments of the present invention, are used to illustrate the concept of the present invention, are illustrative and exemplary, and should not be construed as limiting the embodiments of the present invention and the scope of the present invention. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the contents disclosed in the claims and the description of the present application, and these technical solutions include any obvious technical solutions to the embodiments described herein. Alternative and modified technical solutions.

The accompanying drawings in the present specification are schematic diagrams to assist in explaining the concept of the present invention, and schematically show the shapes of various parts and their mutual relationships. Please note that the same reference numerals are used to denote the same parts in order to clearly represent the structures of the components of the embodiments of the present invention.

FIG. 1 shows a schematic structural diagram of a bio-enhanced intramedullary nail according to the present invention. The bio-enhanced intramedullary nail includes a main nail 10 , a head nail 20 and an injection device 30 . Figure 2 is an exploded view of the components of the bioaugmented intramedullary nail.

The main nail 10 is arranged along the length direction of the femur, and the main nail 10 is composed of a proximal part 11 , a transition part 12 and a distal part 13 , as shown in FIG. 3 ; the proximal part 11 is provided with a fixing hole 14 , which is inclined and disposed through the proximal portion 11, the head nail 20 passes through the fixing hole 14 and is disposed in the femur; the main nail 10 and the head nail 20 are provided with a fluid in communication The injection device 30 is connected with the fluid hole inside the head nail 20 to inject fluid into the inner cavity of the femur through the head nail 20 and the main nail 10 .

In the present invention, the fluid injected by the injection device 30 is a bio-enhanced hydrogel, preferably its components include (1) polyacrylic acid (PAA-NHS) grafted with N-hydrosuccinimide ester, which has bone tissue Adhesion properties; (2) a-cyanoacrylate adhesive (ethyl a-cyanoacrylate), with metal adhesion properties.

The biologically enhanced function of the hydrogel is achieved by the internal loading of drug-loaded microcapsules. Including: promoting blood vessels, promoting bone, promoting bone immunity, anti-infection. Drug loading is achieved through the multi-action of one drug/multi-drug synergistic enhancement. There are hydrogel + 4 kinds of drug-loaded microspheres, which are anti-infection (antibiotic) drug loading, angiogenesis (VEGF) drug loading, bone repair (BMP-2) drug loading, and inflammatory response improvement (IL-10/ 2-Methoxyestradiol and other drugs that can promote the transformation of M1 macrophages to M2 macrophages) drug loading. Therefore, the regenerative microenvironment can be regulated and biologically enhanced.

On the one hand, the hydrogel has both bone adhesion and metal adhesion properties, adhering the intramedullary nail to the bone; on the other hand, the hydrogel can be used as a physical filler to occupy the space between the implanted intramedullary nail and the bone. physical space, and therefore provides stronger mechanical support; the intramedullary nail here refers to the assembly formed by the main and head nails inside the femur. In addition, the hydrogel and drug-loaded microspheres promote the growth of new bone into the channel on the peripheral side wall of the main nail to form a mesh structure, which makes the intramedullary nail tightly integrated with the bone tissue and increases the mechanical stability.

As an embodiment of the present invention, a main nail hole 15 is provided inside the main nail 10 , which extends downward along the length direction of the main nail 10 and is located at the lower part of the fixing hole 14 . It can be understood that, for the convenience of processing, the main nail hole 15 can extend through and extend from the upper end of the main nail 10 to the lower end of the main nail 10 , as shown in FIG. 3 .

FIGS. 4 and 5 are schematic diagrams of the structure of the head nail 20 of the present invention. The head nail 20 is provided with a head nail hole 21 and a vertical hole 22 , and the head nail hole 21 is along the length of the head nail 20 . The vertical hole 22 is arranged along the radial direction of the head nail 20 and communicates with the vertical hole 22 , and the vertical hole 22 communicates with the fluid hole of the main nail 10 . Specifically, the vertical hole 22 communicates with the main nail hole 15 of the main nail 10 .

In FIG. 5 , a limiting groove 23 is provided on the outer peripheral side of the head nail 20 , and the limiting groove 23 is opposite to the vertical hole 22 . The structure of the intramedullary nail described in the present invention is similar to the patent CN111012463A. The upper part of the head nail 10 is also provided with a locking bolt (not shown). Bit slot 23. Since the limiting slot 23 is opposite to the vertical hole 22 , whether the vertical hole 22 is connected to the main nail hole 15 can be determined by whether the locking bolt is clamped in the limiting slot 23 .

In FIG. 3 , the main nail 10 is further provided with a circumferential hole 16 , and the circumferential hole 16 is arranged along the radial direction of the main nail 10 and communicates with the main nail hole 15 . The hydrogel inside the injection device 30 enters the main nail hole 15 of the main nail 10 through the head nail hole 21 and the vertical hole 22 of the head nail 20, and the hydrogel entering the main nail hole 15 spreads evenly to the main nail hole 15 through the circumferential hole 16. intramedullary cavity to ensure the bio-enhancing function of the hydrogel. As an embodiment of the present invention, the circumferential hole 16 is located at the distal end portion 13 of the main nail 10 , and its inner diameter is not greater than the inner diameter of the main nail hole 15 . In the embodiment shown in FIG. 3 , the inner diameter of the circumferential hole 16 is smaller than the inner diameter of the main nail hole 15 . Specifically, the inner diameter of the circumferential hole 16 is 60%-80% of the inner diameter of the main nail hole 15 .

As an embodiment of the present invention, the outer end of the stud 20 is provided with a connecting portion 20 a, and the connecting portion 20 a is coaxially disposed with the stud hole 21 . The outer end of the head nail 20 is also provided with a tightening portion 20b, which enters the fixing hole 14 of the proximal end portion 11 in a rotational manner.

6 is a schematic structural diagram of the injection device according to the present invention. The injection device 30 is connected to the head pin hole 21 through an adaptor 31 and a pipeline, and the adaptor 31 is sealingly connected to the connection portion 20a.

7 is a schematic diagram of an application embodiment of the bio-enhanced intramedullary nail according to the present invention. The main nail 10 is arranged along the length direction of the femur, the head nail 20 passes through the fixing hole 14 and is arranged in the femur, and the injection device 30 is connected to the femur. The fluid holes inside the head nail 20 are connected to inject the hydrogel into the inner cavity of the femur through the head nail 20 and the main nail 10 .

Comparative Test

By comparing the intramedullary nail in the hydrogel group and the intramedullary nail in the non-hydrogel group (common femoral intramedullary nail) between groups, each group has 5 samples, a total of 10 samples to determine which intramedullary nail has stronger torsional stiffness . The test is carried out in a dry and room temperature environment. The test device is shown in Figure 8. The test parameters are shown in Table 1 and Table 2. The slope of the linear portion of the torque-torsion angle curve is the torsional stiffness of the intramedullary nail.

Table 1 Static Torsion Test Parameters

working distance Torsion rate twist angle 70mm 5°/min 5°

Table 2 Hydrogel group

It can be seen from Table 2 that the average torsional stiffness of the hydrogel group is greater than that of the non-hydrogel group.

The results of the biotoxicity test of the hydrogel are shown in Table 3.

Table 3 shows the blood test results

The results in Table 3 show that the hydrogels are not cytotoxic.

Compared with the prior art, the bio-enhanced intramedullary nail provided by the present invention has a reasonable structure, and fluid holes are arranged inside the main nail and the head nail to inject bio-enhanced hydrogel, which not only satisfies the requirements of fracture fixation The mechanical enhancement function also realizes the biological enhancement function of the regulation of the regenerative microenvironment, and solves the technical problems of malunion, insufficient mechanical properties of the healing site, and even nonunion.

The present invention is not limited to the above-mentioned embodiments, and anyone can obtain other various forms of products under the inspiration of the present invention, but no matter if any changes are made in its shape or structure, all products with the same or similar characteristics as those in the present application can be obtained. The technical solutions all fall within the protection scope of the present invention.

Claims (10)

1. A bio-enhanced intramedullary nail, characterized in that it comprises a main nail, a head nail and an injection device; the main nail is arranged along the length direction of the femur, and the main nail consists of a proximal part, a transition part and a distal end. part; the proximal part is provided with a fixing hole, which is inclined and arranged through the proximal part, and the head nail passes through the fixing hole and is set in the femur; the main nail and the head nail are A fluid hole in communication is provided inside, and the injection device is connected with the fluid hole inside the head nail, so as to inject fluid into the inner cavity of the femur through the head nail and the main nail. 2 . The bio-enhanced intramedullary nail according to claim 1 , wherein a main nail hole is provided inside the main nail, which extends downward along the length direction of the main nail and is located at the lower part of the fixing hole. 3 . . 3 . The bio-enhanced intramedullary nail according to claim 1 , wherein a head nail hole and a vertical hole are arranged inside the head nail, and the head nail hole is arranged along the length direction of the head nail. 4 . , the vertical hole is arranged along the radial direction of the head nail and communicates with the vertical hole, and the vertical hole communicates with the fluid hole of the main nail. 4 . The bio-enhanced intramedullary nail according to claim 3 , wherein a limiting groove is provided on the outer peripheral side of the head nail, and the limiting groove is opposite to the vertical hole. 5 . 5 . The bio-enhanced intramedullary nail according to claim 2 , wherein the main nail is further provided with a circumferential hole, and the circumferential hole is arranged along the radial direction of the main nail and is connected with the main nail. 6 . The pores are connected. 6 . The bio-enhanced intramedullary nail according to claim 1 , wherein the fluid injected by the injection device is a bio-enhanced hydrogel. 7 . 7 . The bioaugmented intramedullary nail according to claim 3 , wherein the outer end of the head nail is provided with a connecting part, and the connecting part is coaxial with the head nail hole. 8 . 8 . The bioaugmented intramedullary nail according to claim 7 , wherein the injection device is connected to the head nail hole through an adaptor and a pipeline, and the adaptor is sealedly connected to the connection portion. 9 . 9 . The bioaugmented intramedullary nail according to claim 7 , wherein the outer end of the head nail is further provided with a tightening portion, which enters the fixing hole of the proximal end portion by a rotating manner. 10 . 10 . The bioaugmented intramedullary nail according to claim 5 , wherein the circumferential hole is located at the distal end portion of the main nail, and its inner diameter is not greater than the inner diameter of the main nail hole. 11 .

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