CN216985114U - Intramedullary nail mechanism - Google Patents

Abstract

The utility model provides an intramedullary nail mechanism, comprising: a first implant nail; the second implantation nail penetrates through the first end of the first implantation nail and is obliquely arranged relative to the first implantation nail; the nail is implanted to the third, wear to locate the middle part of first nail of implanting, and set up for the slope of first nail of implanting, wherein, the nail is implanted to the third includes first connection nail section and second connection nail section, can relative movement between first connection nail section and the second connection nail section, the first end and the second of first connection nail section are implanted the nail and are connected, the second connection nail section is worn to establish the middle part at first nail of implanting, be provided with elastic buffer structure between the second end of first connection nail section and the first end of second connection nail section. The technical scheme of the application effectively solves the problem that the intramedullary nail implanted into the femur is cut out to the outside of the femur in the related art.

Description

Intramedullary nail mechanism

Technical Field

The utility model relates to the field of medical instruments, in particular to an intramedullary nail mechanism.

Background

For unstable intertrochanteric fracture of femur, an intramedullary nail is usually adopted for fixation, a first implantation nail passes through a femoral medullary cavity, the eccentric distance is relatively short, the possibility of internal fixation failure after operation is relatively small compared with external fixation, the intramedullary nail is implanted, the connection of fracture parts between the intertrochanteric femurs can be rebuilt, and the limb function of a patient is restored after fracture healing. The existing intramedullary nail mechanism for treating unstable intertrochanteric fracture of femur still has high internal fixation failure rate.

Studies have shown that the medial, lateral and superior walls of the proximal femur are important structural foundations for maintaining the stability of the proximal femur. In theoretical mechanical analysis, the inner side, the outer side and the upper side of a mechanical triangle ("ward triangle") are equivalent. Theoretical analysis shows that the fracture treatment of the proximal femur has to take into account the simultaneous reconstruction of three sides so as to realize the stabilization of the fracture end and avoid treatment failure.

At present, a lever type structure is formed after an intramedullary nail operation, when unstable intertrochanteric fracture of femur is treated, stress of bone tissues bearing load is completely replaced, stress of an internal fixation angulation part is concentrated, and the performance of resisting external lower oblique shearing force is poor. Neglecting the importance of the 'ward triangle' stable supporting structure formed by the tension bone trabecula and the pressure bone trabecula. The stable structure of the triangular support formed by the normal bone tissue is far superior to the lever type structure formed by replacing the normal structure by internal fixation. The intramedullary nails are rigid structures, and the femoral system made of metal materials has overhigh elastic modulus for bone substances, generates stress shielding in the compression process, and is easy to cause the problems that the intramedullary nails implanted in the femoral system are cut out to the outside of the femur and the like.

SUMMERY OF THE UTILITY MODEL

The utility model mainly aims to provide an intramedullary nail mechanism to solve the problem that an intramedullary nail implanted into a femur is cut out of the femur in the related art.

In order to achieve the above object, the present invention provides an intramedullary nail mechanism comprising: a first implant nail; the second implantation nail penetrates through the first end of the first implantation nail and is obliquely arranged relative to the first implantation nail; the third is implanted the nail, wear to locate the middle part of first implantation nail to for the slope of first implantation nail sets up, wherein, the third is implanted the nail and is included first connection nail section and second connection nail section, can relative movement between first connection nail section and the second connection nail section, the first end and the second implantation nail of first connection nail section are connected, the second connection nail section is worn to establish the middle part of first implantation nail, be provided with the springiness cushioning structure between the second end of first connection nail section and the first end of second connection nail section.

Furthermore, the second end of the first connecting nail section is in nested fit with the first end of the second connecting nail section, an inner hole is formed in the second end of the first connecting nail section or the first end of the second connecting nail section, and the elastic buffer structure is located in the inner hole.

Further, the hole setting is connected the first end of nail section at the second, and first connection nail section is worn to establish including downthehole, and the second is connected the nail section and is had this somatic part and cushion collar, and the hole setting is at the tip of this somatic part, and the cushion collar setting is in the hole, and elastic buffer structure is located between the diapire of first connection nail section and hole.

Further, the buffer sleeve is connected in the inner hole through injection molding, welding, bonding or screwing.

Further, the elastic buffer structure comprises a spring; and/or the material of the buffer sleeve is biological polycarbonate polyurethane.

Furthermore, a first rotation stopping portion is arranged at the second end of the first connecting nail section, a second rotation stopping portion is arranged on the buffer sleeve, and the first rotation stopping portion is matched with the second rotation stopping portion in a rotation stopping mode.

Further, first rotation stopping portion includes the axial groove, and second rotation stopping portion includes the axial rib with the axial groove grafting cooperation.

Further, the axial dimension of the axial groove is greater than the axial dimension of the axial rib.

Furthermore, a screw hole is formed in the second implant nail, the axis of the screw hole is parallel to the axis of the first connecting nail section, and the first connecting nail section is provided with a first thread section matched with the screw hole in a threaded mode.

Further, the first connecting nail section comprises a first thread section and a first polished rod section connected with the first thread section; the second connecting nail section comprises a second thread section, a second polished rod section and a third thread section connected between the second thread section and the second polished rod section, the outer diameter of the second thread section is smaller than that of the outer wall of the second polished rod section, the elastic buffer structure is arranged between the first polished rod section and the second thread section, an operation hole is formed in one end, far away from the third thread section, of the second polished rod section, and a second end of the second connecting nail section is formed in one end, far away from the third thread section, of the second polished rod section; the first end of the second implantation nail is provided with an external thread, the second end of the second implantation nail is provided with an operation groove, and the first end of the first connecting nail section is connected to the external thread; the first implantation nail comprises a first nail section and a second nail section connected with the first nail section, and the outer diameter of the first nail section is larger than that of the second nail section; the second implantation nail penetrates through the first end of the first nail section, and the first end of the second connection nail section and the second end of the second connection nail section are respectively positioned on two sides of the second end of the first nail section; the intramedullary nail mechanism further comprises a transverse nail which is arranged on the second nail section in a penetrating mode.

By applying the technical scheme of the utility model, the intramedullary nail mechanism comprises: a first implant nail, a second implant nail, and a third implant nail. The second implantation nail penetrates through the first end of the first implantation nail and is obliquely arranged relative to the first implantation nail. The third implantation nail penetrates through the middle part of the first implantation nail and is obliquely arranged relative to the first implantation nail, so that a triangular area is defined among the first implantation nail, the second implantation nail and the third implantation nail. Wherein, the nail is implanted to the third includes that first connection nail section and second are connected the nail section, can relative movement between first connection nail section and the second connection nail section, and the first end and the second of first connection nail section are implanted the nail and are connected, and the middle part at first implantation nail is worn to establish by the second connection nail section, is provided with elastic buffer structure between the second end of first connection nail section and the first end of second connection nail section. In the process that the intramedullary nail mechanism is implanted into a femur, a first implantation nail is driven, a second implantation nail penetrates through the first end of the first implantation nail, the fracture end is pressurized through the second implantation nail, a third implantation nail penetrates through the middle of the first implantation nail, and the first end of a first connecting nail section is connected with the second implantation nail. After the intramedullary nail mechanism is implanted, the whole intramedullary nail mechanism bears pressure, and transmits the pressure to the first end of the first connecting nail section, so that the third implanted nail is pressed, the elastic buffer structure between the second end of the first connecting nail section and the first end of the second connecting nail section is pressed to be in a compression state, and generates damping force on the first connecting nail section, the second end of the first connecting nail section is gradually close to the first end of the second connecting nail section, so that the whole length of the third implanted nail is gradually reduced, the pressure energy born by the intramedullary nail mechanism is stored and dispersed by the elastic buffer structure, the stress balance of the intramedullary nail mechanism and the better dispersion of the born pressure are ensured, the load born by the intramedullary nail mechanism at the moment is relieved and weakened through the retraction and the releasing of the elastic buffer structure, the elastic modulus of the intramedullary nail mechanism is reduced, and the stress shielding is reduced. Therefore, the 'ward triangle' can be effectively reconstructed, the stably supported intramedullary nail mechanism is realized, effective reduction and fixation of the femoral head of a patient can be well realized, the 'ward triangle' of the femoral trochanter can be reconstructed, the stress borne by the femur can be better dispersed, and the intramedullary nail mechanism implanted into the femur is prevented from being cut out of the femur. Therefore, the technical scheme of the application can solve the problem that the intramedullary nail implanted into the femur is cut out to the outside of the femur in the related art.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the utility model and, together with the description, serve to explain the utility model and not to limit the utility model. In the drawings:

fig. 1 shows a perspective schematic view of an intramedullary nail mechanism implanted in a femur according to an embodiment of the intramedullary nail mechanism of the present invention;

fig. 2 shows a perspective view of the intramedullary nail mechanism of fig. 1;

FIG. 3 shows a cross-sectional schematic view of the intramedullary nail mechanism of FIG. 2;

fig. 4 shows an enlarged schematic view at a of the intramedullary nail mechanism of fig. 3;

FIG. 5 shows a schematic front view of the intramedullary nail mechanism of FIG. 2;

FIG. 6 shows a cross-sectional schematic view of the intramedullary nail mechanism of FIG. 5;

fig. 7 shows an exploded schematic view of the intramedullary nail mechanism of fig. 2;

FIG. 8 is a perspective view of a first connecting nail segment and a buffer sleeve of the intramedullary nail mechanism of FIG. 7;

FIG. 9 shows a cross-sectional schematic view of the intramedullary nail mechanism of FIG. 7;

fig. 10 shows an enlarged schematic view at B of the intramedullary nail mechanism of fig. 9;

fig. 11 shows a perspective view of another angle of the intramedullary nail mechanism of fig. 2;

fig. 12 shows a perspective view of a second implant nail of the intramedullary nail mechanism of fig. 2;

fig. 13 is a perspective view of another angle of a second implant nail of the intramedullary nail mechanism of fig. 2;

FIG. 14 shows a cross-sectional schematic view of the second implant nail of FIG. 13;

fig. 15 shows a schematic front view of a first implant nail of the intramedullary nail mechanism of fig. 2;

fig. 16 shows a front view schematic of a second implant nail of the intramedullary nail mechanism of fig. 2.

Wherein the figures include the following reference numerals:

4. a femur; 10. a first implant nail; 11. a first nail section; 12. a second nail section; 20. a second implant pin; 21. an external thread; 22. an operation slot; 23. a screw hole; 211. a first lever body portion; 212. a second shaft portion; 216. screw teeth; 201. a first trench; 202. a second trench; 30. a third implantation nail; 31. a first connecting nail section; 311. a first polished rod segment; 312. a first thread segment; 32. a second connecting nail section; 321. a second thread segment; 322. a second polished rod segment; 3221. an operation hole; 323. a third thread segment; 33. an inner bore; 35. an axial slot; 36. axial ribs; 37. connecting columns; 40. an elastic buffer structure; 41. a spring; 42. a buffer sleeve; 50. and (4) transverse nailing.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the utility model, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be discussed further in subsequent figures.

As shown in fig. 1 to 6, the intramedullary nail mechanism of the present embodiment includes: a first implant nail 10, a second implant nail 20, and a third implant nail 30. The second implant pin 20 is inserted through the first end of the first implant pin 10 and is disposed obliquely with respect to the first implant pin 10. The third implant pin 30 is inserted through the middle of the first implant pin 10 and is obliquely disposed with respect to the first implant pin 10 such that a triangular region is defined between the first implant pin 10, the second implant pin 20, and the third implant pin 30. Wherein, the third is implanted and is followed closely 30 including first connection nail section 31 and second connection nail section 32, and first connection nail section 31 and second are connected and can move relatively between the nail section 32, and the first end of first connection nail section 31 is implanted with the second and is followed closely 20 and be connected, and the middle part at first nail 10 of implanting is worn to establish by second connection nail section 32, is provided with elastic buffer structure 40 between the second end of first connection nail section 31 and the first end of second connection nail section 32.

The teachings of the present embodiment are applied such that a triangular region is defined between first implant nail 10, second implant nail 20, and third implant nail 30. The third implantation nail 30 comprises a first connection nail section 31 and a second connection nail section 32, the first connection nail section 31 and the second connection nail section 32 can move relatively, the first end of the first connection nail section 31 is connected with the second implantation nail 20, the second connection nail section 32 penetrates through the middle of the first implantation nail 10, and an elastic buffer structure 40 is arranged between the second end of the first connection nail section 31 and the first end of the second connection nail section 32. In the process of implanting the intramedullary nail mechanism into the femur 4, the first implantation nail 10 is driven, the second implantation nail 20 is arranged at the first end of the first implantation nail 10 in a penetrating way, the fracture end is pressurized through the second implantation nail 20, the third implantation nail 30 is arranged at the middle part of the first implantation nail 10 in a penetrating way, and the first end of the first connecting nail section 31 is connected with the second implantation nail 20. After the intramedullary nail mechanism is implanted, the intramedullary nail mechanism is wholly pressed and transmits the pressure to the first end of the first connecting nail section 31, so that the third implanted nail 30 is pressed, the elastic buffer structure 40 between the second end of the first connecting nail section 31 and the first end of the second connecting nail section 32 is pressed to be in a compressed state, and generates a damping force to the first coupling nail section 31, the second end of the first coupling nail section 31 gradually approaches with respect to the first end of the second coupling nail section 32, so that the overall length of the third implanted nail 30 is gradually reduced, the pressure energy borne by the intramedullary nail mechanism is stored and dispersed by the elastic buffer structure 40, the stress balance of the intramedullary nail mechanism and the better dispersion of the borne pressure are ensured, the load instantaneously born by the intramedullary nail mechanism is relieved and weakened through the retraction of the elastic buffer structure 40, the elastic modulus of the intramedullary nail mechanism is reduced, and the stress shielding is reduced. Therefore, the 'ward triangle' can be effectively reconstructed, the stably supported intramedullary nail mechanism is realized, effective reduction and fixation of the femoral head of a patient can be well realized, the 'ward triangle' of the femoral trochanter can be reconstructed, the stress borne by the femur can be better dispersed, and the intramedullary nail mechanism implanted into the femur is prevented from being cut out of the femur. Therefore, the technical solution of the present embodiment can solve the problem of cutting the intramedullary nail implanted into the femur out of the femur in the related art.

It should be noted that, the first connecting nail section 31 and the second connecting nail section 32 can move relative to each other, which means that one of the first connecting nail section 31 and the second connecting nail section 32 is fixed, and the other one of the first connecting nail section 31 and the second connecting nail section 32 can move; or both the first connecting pin section 31 and the second connecting pin section 32 can be movable.

It should be noted that the middle of the first implant pin 10 is a position located between the first end of the first implant pin 10 and the second end of the first implant pin 10. The second implant nail 20 of this embodiment supports primarily the tension trabecular bone in the femur, and the third implant nail 30 supports primarily the tension trabecular bone in the femur.

As shown in fig. 3 and 4, in the relative movement process of the first connecting nail section 31 and the second connecting nail section 32, in order to enable the first connecting nail section 31 and the second connecting nail section 32 to move smoothly, the second end of the first connecting nail section 31 and the first end of the second connecting nail section 32 are in nested fit, the first end of the second connecting nail section 32 is provided with an inner hole 33, and the elastic buffer structure 40 is located in the inner hole 33. Meanwhile, the elastic buffer structure 40 located in the inner hole 33 can limit the elastic buffer structure 40, and prevent the elastic buffer structure 40 from being separated from the first end of the second connecting nail section 32.

Of course, in the embodiment not shown in the figures, the second end of the first connecting nail section and the first end of the second connecting nail section are in nested fit, the second end of the first connecting nail section can be provided with an inner hole, and the elastic buffer structure is positioned in the inner hole.

As shown in fig. 3 to 11, the inner hole 33 is disposed at the first end of the second connecting pin segment 32, and the first connecting pin segment 31 is disposed in the inner hole 33. The second staple section 32 has a body portion and a bumper sleeve 42. The internal bore 33 is provided at the end of the body portion, the damping sleeve 42 is provided in the internal bore 33, and the resilient damping structure 40 is located between the first attachment pin section 31 and the bottom wall of the internal bore 33. Like this, the second end of first connection nail section 31 wears to establish in cushion collar 42, in first connection nail section 31 and the relative movement in-process of second connection nail section 32, cushion collar 42 can cushion the pressure that first connection nail section 31 bore on the one hand, on the other hand cushion collar 42 can the guide fit with the outer wall of the second end of first connection nail section 31, so that the second end of first connection nail section 31 can smoothly move in cushion collar 42, so that the second end extrusion elastic buffer structure 40 of first connection nail section 31, so that the pressure that first connection nail section 31 receives smoothly transmits to elastic buffer structure 40 on.

As shown in fig. 3 to 11, in order to secure the connection strength between the cushion sleeve 42 and the body portion, the cushion sleeve 42 is connected in the inner hole 33 by injection molding. Specifically, in order to ensure the connection effect of the injection-molded connection of the buffer sleeve 42 in the inner hole 33, as shown in fig. 10 and 11, a connection post 37 is provided on the inner wall of the inner hole 33, and during the injection-molded connection of the buffer sleeve 42 in the inner hole 33, the connection post 37 is melted to fill a gap in the radial direction between the buffer sleeve 42 and the inner hole 33, so as to firmly connect the buffer sleeve 42 and the body part together.

In an embodiment not shown in the figures, the damping sleeve is connected in the inner bore by welding, gluing or screwing.

As shown in fig. 1 to 11, in order to simultaneously optimize the structural layout, facilitate the production, manufacture and installation, the elastic buffer structure 40 includes a spring 41. The material of the buffer sleeve is biological polycarbonate Polyurethane (PCU). The biological polycarbonate type polyurethane material has good strength, certain flexibility and elasticity and can meet certain elastic deformation. The deformation of the spring 41 is used to relieve and weaken the instantaneous load of the intramedullary nail mechanism, so that the third implanted nail 30 can provide a certain elastic support, the intramedullary nail mechanism has elasticity, the possibility of stress concentration of the intramedullary nail mechanism is effectively reduced, and the service life of the intramedullary nail assembly is prolonged. In particular, the intramedullary nail mechanism is located at a proximal position of the femur 4, i.e. proximal femur.

Of course in other embodiments, the resilient cushioning structure comprises a spring; or the material of the buffer sleeve is biological polycarbonate polyurethane.

As shown in fig. 3, 4 and 8, the second end of the first connecting nail section 31 is provided with a first rotation stopping portion, the cushion sleeve 42 is provided with a second rotation stopping portion, and the first rotation stopping portion is engaged with the second rotation stopping portion in a rotation stopping manner. Like this, through the cooperation of the second portion of splines and the first portion of splines, when the screw in second is connected the nail section 32, first connection nail section 31 can be connected the nail section 32 along with the second and rotate together to make the third implant nail 30 can wear to establish the middle part of first implant nail 10, and make the first end of first connection nail section 31 connect on the second implants nail 20.

As shown in fig. 3, 4 and 8, the first rotation stop portion includes an axial groove 35, and the second rotation stop portion includes an axial rib 36 which is in plug-fit engagement with the axial groove 35. Like this, when first connection nail section 31 atress and for second connection nail section 32 removal, axial rib 36 can move in axial groove 35, plays the guide effect, and simultaneously, the groove lateral wall of axial groove 35 and the contact of the lateral wall of axial rib 36 prevent that first connection nail section 31 from taking place to rotate for second connection nail section 32.

As shown in fig. 3, 4 and 8, the axial dimension of the axial groove 35 is greater than the axial dimension of the axial ribs 36 in order to enable the axial ribs 36 to move within the axial groove 35. In this way, the axial ribs 36 slide smoothly along the axial grooves 35 to ensure a certain movement distance of the axial ribs 36.

As shown in fig. 3, 4 and 8, the axial grooves 35 are four grooves spaced at intervals along the circumference of the second end of the first connecting pin section 31, the axial ribs 36 are four grooves spaced at intervals along the circumference of the first end of the second connecting pin section 32, and the four axial grooves 35 and the four axial ribs 36 are arranged in a one-to-one correspondence. This allows the third implant nail 30 to have sufficient structural strength when the second connecting nail section 32 twists the first connecting nail section 31, which can ensure the structural stability of the third implant nail 30. The number of axial grooves 35 and axial ribs 36 may not be limited to four, but may also be one, two, three, five or more.

As shown in fig. 3, 4, 8, 12 to 14, the third implantation nail 30 is inserted into the middle of the first implantation nail 10, and since the second implantation nail 20 is provided with the screw hole 23, the axis of the screw hole 23 is parallel to the axis of the first connection nail section 31. The first connecting pin section 31 has a first threaded section 312 that is threadedly engaged with the threaded bore 23. Thus, the first end of the first connecting nail section 31 is smoothly introduced into the screw hole 23 of the second implant nail 20, and the third implant nail 30 is continuously screwed in, so that the first thread section 312 can be screwed in the screw hole 23, thereby connecting the first end of the first connecting nail section 31 to the second implant nail 20.

As shown in fig. 1 to 6 and 12 to 14, the first connecting pin segment 31 includes a first thread segment 312 and a first polished rod segment 311 connected to the first thread segment. In this way, the provision of the first thread section 312 facilitates the screwing of the first connection nail section 31 into the femur 4 and enables the connection in the screw hole 23, ensuring a reliable implantation stability of the first connection nail section 31. The first polished rod section 311 can reduce the resistance generated in the process of screwing the first connecting nail section 31 into the femur 4, and can enable the first connecting nail section 31 to be smoothly screwed into the position connected with the screw hole 23.

As shown in fig. 2 to 6, the second connecting pin segment 32 includes a second thread segment 321, a second polished rod segment 322, and a third thread segment 323 connected between the second thread segment 321 and the second polished rod segment 322. The outer diameter of the second screw thread section 321 is smaller than the outer diameter of the outer wall of the second light rod section 322, and the elastic buffer structure 40 is arranged between the first light rod section 311 and the second screw thread section 321. In this way, the third threaded section 323 is arranged to facilitate the connection of the second connection nail section 32 to the first implantation nail 10, and the second polished rod section 322 is arranged to reduce the resistance generated in the process of screwing the second connection nail section 32 into the femur 4, so that the second connection nail section 32 can be smoothly screwed into the position where the third threaded section 323 is connected to the middle part of the first implantation nail 10.

As shown in fig. 2 to 6, an operation hole 3221 is disposed at an end of the second light rod section 322 far from the third thread section 323. The end of the second polished rod section 322 remote from the third threaded section 323 forms a second end of the second connecting nail section 32. The operation hole 3221 is configured to drive the second polished rod segment 322 to rotate, and the operation hole 3221 is preferably a hexagon socket so that a hexagon socket wrench can be used to insert into the operation hole 3221 and can drive the second connecting nail segment 32 to rotate, so that the third implantation nail 30 can achieve a reduction compression effect on the fractured end.

As shown in fig. 2 to 6, the first end of the second implant pin 20 is provided with an external thread 21. The second end of the second implant pin 20 is provided with an operation slot 22, and the first end of the first connection pin 31 is connected to the external thread 21. The provision of the external thread 21 facilitates the screwing of the second implantation nail 20 into the femur 4, and the provision of the operation slot 22 facilitates the operation. The first end of the first connecting nail section 31 is connected to the external thread 21, so that the occlusion locking can be performed, and the supporting effect of the third implantation nail 30 is improved. After the second implantation nail 20 is implanted in the femur 4, the second end of the second implantation nail 20 can be exposed out of the outer sidewall of the femur 4, so that the operation slot 22 on the second end of the second implantation nail 20 can also be exposed out of the femur 4. The operation slot 22 may be driven using a screwdriver tool.

As shown in fig. 3 and 16, the external thread 21 includes a shaft portion and a thread 216 disposed on the shaft portion, and the thread 216 is provided with a plurality of first grooves 201. When the second implant nail 20 is stressed, the external thread 21 of the second implant nail 20 compresses bone substances in the femur when being screwed in, the screw teeth 216 provided with the plurality of first grooves 201 enable the screw teeth 216 to have elasticity and generate micro deformation, the elastic modulus of the intramedullary locking nail component is reduced, the screw teeth 216 can be adaptive to the bone substances around the screw teeth 216, so that the bone substances around the screw teeth 216 are inserted into the first grooves 201 to be occluded and locked, stress shielding is reduced, and the bone substances can be effectively prevented from being further cut and the second implant nail 20 can be effectively prevented from penetrating out of the femur.

As shown in fig. 3 and 16, when the external thread 21 of the second implant nail 20 is screwed in, the bone material in the femur is compressed, because the plurality of first grooves 201 on the same circle of the screw teeth 216 are radially arranged, so that each first groove 201 is adapted to the embedded bone material, and the radially arranged plurality of first grooves 201 can engage more bone material while reducing the elastic modulus of the second implant nail 20, so that the screw teeth 216 can effectively adapt to the surrounding bone material.

It should be noted that, the plurality of first grooves 201 are radially arranged, which means that the side walls of the plurality of first grooves 201 may diverge in a straight line direction or in a curved line direction.

As shown in fig. 3 and 16, the height of the thread 216 of the external thread 21 is gradually reduced from the distance from the first implant nail 10 to the distance from the first implant nail 10. Thus, the portion of the thread 216 of the external thread 21 distant from the first implant nail 10 is higher and deeper embedded in the bone, and can bite the bone, and at the same time, since the portion of the thread 216 of the external thread 21 close to the first implant nail 10 is lower and higher in strength, it is possible to provide sufficient strength to the portion of the thread 216 distant from the first implant nail 10.

As shown in fig. 3 and 16, the rod body portion includes a first rod body portion 211 and a second rod body portion 212, the first rod body portion 211 is of a polished rod structure, and a portion of the second rod body portion 212 located between two adjacent threads 216 is provided with a plurality of second grooves 202. Thus, in the process of compressing the bone in the femur when the external thread 21 of the second implantation nail 20 is screwed in, since the first rod body portion 211 is of a polished rod structure, the screwing resistance of the external thread 21 can be reduced, so that the screw teeth 216 on the first rod body portion 211 can be screwed into deeper bone, and more bone can be simultaneously embedded into the first grooves 201 and the second grooves 202, so that the elastic modulus of the second implantation nail 20 is closer to that of the bone, the self-adaptation condition of the screw teeth 216 and the surrounding bone is met, and the bone cutting and the second implantation nail 20 can be further prevented from penetrating out of the femur 4.

As shown in fig. 2 to 6 and 15, the first implant nail 10 includes a first nail section 11 and a second nail section 12 connected to the first nail section 11. The first staple section 11 has an outer diameter greater than the outer diameter of the second staple section 12. The second implantation nail 20 is inserted into the first end of the first nail section 11, and the first end of the second connection nail section 32 and the second end of the second connection nail section 32 are respectively located at two sides of the second end of the first nail section 11. In this way, the second polished rod section 322 has a longer length, so that the second end of the second polished rod section 322 can be exposed to the outer sidewall of the femur 4 after the third implantation nail 30 is implanted in the femur 4, so that the operation hole 3221 on the second polished rod section 322 can also be exposed to the outside of the femur 4. And because the outer diameter of the first nail section 11 is larger than that of the second nail section 12, the first nail section 11 has enough structural strength, and the installation position of the second implant nail 20 and the installation position of the third implant nail 30 are convenient to arrange on the first nail section 11. The intramedullary nail mechanism further includes a transverse nail 50 disposed through the second nail section 12. The provision of the transverse nail 50 facilitates locking of the second nail section 12 into the femur, improving the stability of the overall structure of the intramedullary nail mechanism.

The body portions, the second threaded section 321, and the third threaded section 323 of the first implant nail 10, the second implant nail 20, the first connecting nail section 31, and the second connecting nail section 32 in the present embodiment are preferably made of medical titanium alloy material. Thus, the medical titanium alloy material and the biological polycarbonate type polyurethane material can be connected by injection molding.

In the description of the present invention, it is to be understood that the directions or positional relationships indicated by the directional terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are generally based on the directions or positional relationships shown in the drawings, and are for convenience of description and simplicity of description only, and in the case of not making a reverse description, these directional terms do not indicate and imply that the device or element referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … … surface," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and unless otherwise stated, the terms have no special meaning, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. An intramedullary nail mechanism, comprising:

a first implantation nail (10);

the second implantation nail (20) penetrates through the first end of the first implantation nail (10) and is obliquely arranged relative to the first implantation nail (10);

a third implantation nail (30) which is arranged in the middle of the first implantation nail (10) in a penetrating way and is obliquely arranged relative to the first implantation nail (10),

the third implanted nail (30) comprises a first connecting nail section (31) and a second connecting nail section (32), the first connecting nail section (31) and the second connecting nail section (32) can move relatively, the first end of the first connecting nail section (31) is connected with the second implanted nail (20), the second connecting nail section (32) penetrates through the middle of the first implanted nail (10), and an elastic buffer structure (40) is arranged between the second end of the first connecting nail section (31) and the first end of the second connecting nail section (32).

2. The intramedullary nail mechanism according to claim 1, characterized in that the second end of the first connection nail segment (31) and the first end of the second connection nail segment (32) are nested, the second end of the first connection nail segment (31) or the first end of the second connection nail segment (32) being provided with an inner bore (33), the resilient buffer structure (40) being located within the inner bore (33).

3. The intramedullary nail mechanism according to claim 2, wherein the internal bore (33) is provided at a first end of the second connection nail section (32), the first connection nail section (31) is inserted into the internal bore (33), the second connection nail section (32) has a body portion and a buffer sleeve (42), the internal bore (33) is provided at an end portion of the body portion, the buffer sleeve (42) is provided in the internal bore (33), and the elastic buffer structure (40) is located between the first connection nail section (31) and a bottom wall of the internal bore (33).

4. The intramedullary nail mechanism of claim 3, wherein the buffer sleeve (42) is injection molded, welded, bonded or screwed within the bore (33).

5. The intramedullary nail mechanism according to claim 3, wherein the elastic buffer structure (40) comprises a spring (41); and/or the material of the buffer sleeve is biological polycarbonate polyurethane.

6. The intramedullary nail mechanism according to claim 3, wherein the second end of the first connecting nail section (31) is provided with a first rotation stop portion, the buffer sleeve (42) is provided with a second rotation stop portion, and the first rotation stop portion is engaged with the second rotation stop portion in a rotation stop manner.

7. The intramedullary nail mechanism according to claim 6, wherein the first rotation stop portion comprises an axial groove (35) and the second rotation stop portion comprises an axial rib (36) in plug-fit engagement with the axial groove (35).

8. Intramedullary nail mechanism according to claim 7, characterized in that the axial dimension of the axial grooves (35) is greater than the axial dimension of the axial ribs (36).

9. The intramedullary nail mechanism according to claim 1, characterized in that the second implant nail (20) is provided with a screw hole (23), the axis of the screw hole (23) being parallel to the axis of the first connecting nail section (31), the first connecting nail section (31) having a first threaded section (312) which is threadedly engaged with the screw hole (23).

10. The intramedullary nail mechanism of claim 1,

the first connecting nail section (31) comprises a first thread section (312) and a first polished rod section (311) connected with the first thread section;

the second connecting nail section (32) comprises a second thread section (321), a second polished rod section (322) and a third thread section (323) connected between the second thread section (321) and the second polished rod section (322), the outer diameter of the second thread section (321) is smaller than the outer diameter of the outer wall of the second polished rod section (322), the elastic buffer structure (40) is arranged between the first polished rod section (311) and the second thread section (321), an operation hole (3221) is formed in one end, far away from the third thread section (323), of the second polished rod section (322), and a second end of the second connecting nail section (32) is formed in one end, far away from the third thread section (323), of the second polished rod section (322);

the first end of the second implantation nail (20) is provided with an external thread (21), the second end of the second implantation nail (20) is provided with an operation groove (22), and the first end of the first connection nail section (31) is connected to the external thread (21);

the first implantation nail (10) comprises a first nail section (11) and a second nail section (12) connected with the first nail section (11), wherein the outer diameter of the first nail section (11) is larger than that of the second nail section (12);

the second implantation nail (20) penetrates through the first end of the first nail section (11), and the first end of the second connection nail section (32) and the second end of the second connection nail section (32) are respectively positioned on two sides of the second end of the first nail section (11);

the intramedullary nail mechanism further comprises a transverse nail (50) arranged on the second nail section (12).

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