CN216985113U - Intramedullary nail device - Google Patents

Abstract

The present invention provides an intramedullary nail device, comprising: a first nail body; the second nail body is obliquely arranged at the first end of the first nail body in a penetrating way; the third nail body obliquely penetrates through the middle of the first nail body, the third nail body supports the second nail body, so that a triangular area is defined among the first nail body, the second nail body and the third nail body, the third nail body comprises a first nail body section and a second nail body section movably matched with the first nail body section, the first end of the first nail body section supports the second nail body, the second nail body section penetrates through the middle of the first nail body, and a buffer cylinder is arranged between the second end of the first nail body section and the first end of the second nail body 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 device

Technical Field

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

Background

Proximal femoral (femoral neck and intertrochanteric) fractures account for 90% of hip fractures. The proportion of unstable intertrochanteric femoral fractures of old patients is gradually increased after trauma due to osteoporosis, the disability rate of proximal femoral fractures per year is as high as 50%, and even if active treatment and rehabilitation training are carried out, the death rate is still 20% -30% within 1 year.

For femoral intertrochanteric fractures, femoral intramedullary nail fixation is generally adopted, and the probability of internal fixation failure after main nail operation of femoral intramedullary nails is low. The femoral intramedullary nail can rebuild the connection of the fracture part, promote the fracture healing and reduce the complication. The intramedullary nail of femur has been widely used in fracture between the femoral tuberosity, in the actual use process, the higher internal fixation failure condition still exists in the discovery.

As shown in fig. 1, important structures for maintaining the stability of the proximal femur include the medial 1, lateral 2 and superior 3 lateral walls of the proximal femur to form a triangle-like shape.

The stability of the triangular support structure formed by normal bone tissue is obviously superior to that of the lever-like structure formed by the internal intramedullary nail. The intramedullary nail is made of metal materials and has a rigid structure, so that the formed femoral system has stress shielding (due to overhigh elastic modulus of the femoral system) in the compression process for bone, and the implanted intramedullary nail is easy to cut out of the femur or the internal fixation fails.

SUMMERY OF THE UTILITY MODEL

The main objective of the present invention is to provide an intramedullary nail device to solve the problem of cutting out an intramedullary nail implanted into a femur to the outside of the femur in the related art.

In order to achieve the above object, the present invention provides an intramedullary nail device comprising: a first nail body; the second nail body is obliquely arranged at the first end of the first nail body in a penetrating way; the third nail body obliquely penetrates through the middle of the first nail body, the third nail body supports the second nail body, so that a triangular area is defined among the first nail body, the second nail body and the third nail body, the third nail body comprises a first nail body section and a second nail body section movably matched with the first nail body section, the first end of the first nail body section supports the second nail body, the second nail body section penetrates through the middle of the first nail body, and a buffer cylinder is arranged between the second end of the first nail body section and the first end of the second nail body section.

Further, the cushion cylinder comprises a cylinder body and a piston rod penetrating through the cylinder body, one of the piston rod and the cylinder body is arranged at the second end of the first nail body section, and the other one of the piston rod and the cylinder body is arranged at the first end of the second nail body section.

Furthermore, a first rotation stopping part is arranged on the side wall of the second end of the first nail body section or the side wall of the first end of the second nail body section, and a second rotation stopping part matched with the first rotation stopping part in a rotation stopping mode is arranged on the side wall of the cylinder body.

Further, the piston rod sets up on the terminal surface of the second end of first nail body section, and the cylinder body setting is served at the second of first nail body section, and the second pot head of first nail body section is established outside the cylinder body, and first rotation stopping portion is including setting up the axial groove on the inner wall of the second end of first nail body section, and second rotation stopping portion includes the axial rib with axial groove grafting complex.

Furthermore, the piston rod comprises a piston positioned in the cylinder body and a rod body connected with the piston, the rod body penetrates through the mounting hole of the cylinder body, and the intramedullary nail device further comprises a sealing element arranged between the rod body and the mounting hole.

Further, the piston separates the inner cavity of the cylinder body to form a first chamber and a second chamber, and an overflowing hole communicated with the first chamber and the second chamber is formed in the piston.

Further, the intramedullary nail device further comprises an elastic member disposed between the second end of the first nail body segment and the first end of the second nail body segment.

Furthermore, the cylinder body is arranged at the first end of the second nail body section, the axial ribs are arranged at the end part of the cylinder body, the intramedullary nail device further comprises an elastic part arranged between the second end of the first nail body section and the first end of the second nail body section, the elastic part comprises a spring sleeved outside the cylinder body, and the spring is positioned between the axial ribs and the first end of the second nail body section; the piston rod and the first nail body section are of a split structure and are connected through welding, bonding or screwing, and the cylinder body and the second nail body section are of a split structure and are connected through welding, bonding or screwing.

Further, the first nail body section comprises a first polished rod section and a first threaded section connected with the first polished rod section, the piston rod is connected with the first polished rod section, and the first threaded section supports the second nail body; the second nail body section comprises a second polished rod section, a third polished rod section and a second threaded section connected between the second polished rod section and the third polished rod section, the outer diameter of the second polished rod section is smaller than that of the outer wall of the third polished rod section, the cylinder body is connected with the second polished rod section, and the second end of the second nail body section is formed at one end, provided with an operation hole, of the third polished rod section.

Furthermore, the first end of the second nail body is provided with an external thread, the second end of the second nail body is provided with an operation groove, and the first end of the first nail body section supports the external thread; the first nail body comprises a third nail body section and a fourth nail body section connected with the third nail body section, the outer diameter of the third nail body section is larger than that of the fourth nail body section, the second nail body penetrates through the first end of the third nail body section, and the first end of the second nail body section and the second end of the second nail body section are respectively positioned on two sides of the second end of the third nail body section; the intramedullary nail device further comprises a transverse nail which is arranged on the fourth nail body section in a penetrating mode.

By applying the technical scheme of the utility model, the intramedullary nail device comprises: the nail comprises a first nail body, a second nail body and a third nail body. The second nail body obliquely penetrates through the first end of the first nail body. The third nail body obliquely penetrates through the middle part of the first nail body. The third nail body supports the second nail body, so that a triangular area is defined among the first nail body, the second nail body and the third nail body. Wherein, the third nail body includes first nail body section and with the movable complex second nail body section of first nail body section, the second nail body is supported to the first end of first nail body section, the middle part at first nail body is worn to establish by the second nail body section, is provided with the cushion cylinder between the second end of first nail body section and the first end of second nail body section. In the process of implanting the intramedullary nail device into a femur, a first nail body is driven in, a second nail body penetrates through the first end of the first nail body, the fracture end is pressurized through the second nail body, a third nail body penetrates through the middle of the first nail body, and the third nail body supports the second nail body. After implanting the intramedullary nail device, the first end pressurized of first nail body section, cushion cylinder pressurized between the second end of first nail body section and the first end of second nail body section is in the withdrawal state, and produce damping force to first nail body section, the second end of first nail body section is close to gradually for the first end of second nail body section, make the holistic length of third nail body diminish gradually, the pressure energy that the intramedullary nail device bore is stored and the dispersion by the cushion cylinder, put through the withdrawal of cushion cylinder and alleviate the load that the intramedullary nail device bore in the twinkling of an eye, the elastic modulus of intramedullary nail device has been reduced, stress shielding has been reduced. Therefore, the 'ward triangle' can be effectively reconstructed, the stably supported intramedullary nail device can be 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 device 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, are included to provide a further understanding of the utility model, and are incorporated in and constitute a part of this specification, illustrate embodiment(s) 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 schematic view of a "ward triangle" formed under the proximal end of a theoretical mechanical analysis femur in the related art;

fig. 2 shows a perspective schematic view of an intramedullary nail device implanted in a femur according to an embodiment of the intramedullary nail device of the present invention;

FIG. 3 illustrates a front view schematic of the intramedullary nail device of FIG. 2;

fig. 4 shows a cross-sectional schematic view of the intramedullary nail device of fig. 2;

fig. 5 shows a perspective view of a third shank of the intramedullary nail device of fig. 2;

FIG. 6 shows a schematic cross-sectional view of the third shank of FIG. 5;

FIG. 7 shows an exploded view of the third shank of FIG. 5;

FIG. 8 shows a schematic exploded view at another angle of the third shank of FIG. 5;

FIG. 9 shows a cross-sectional schematic view at another angle of the third shank of FIG. 8, after disassembly; and

fig. 10 shows a schematic front view of a first pin body of the intramedullary nail device of fig. 2;

fig. 11 shows a schematic front view of a second shank of the intramedullary nail device of fig. 2.

Wherein the figures include the following reference numerals:

1. an inner sidewall; 2. an outer sidewall; 3. an upper sidewall; 4. the femur; 10. a first nail body; 11. a third nail body section; 12. a fourth nail body section; 20. a second nail body; 21. an external thread; 22. an operation slot; 211. a first lever body portion; 212. a second shaft portion; 213. a first stopper groove; 214. a second stopper groove; 216. screw teeth; 201. a first trench; 23. a second trench; 30. a third nail body; 31. a first nail body section; 311. a first polished rod segment; 312. a first thread segment; 32. a second nail body section; 321. a second polished rod segment; 322. a third polished rod segment; 3221. an operation hole; 323. a second thread segment; 34. an axial slot; 35. axial ribs; 40. a cushion cylinder; 41. a cylinder body; 42. a piston rod; 421. a piston; 4211. an overflowing hole; 422. a rod body; 50. transverse nails; 60. an elastic member.

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 it is 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, further discussion thereof is not required in subsequent figures.

As shown in fig. 2 to 6 and 10, the intramedullary nail device of the present embodiment includes: a first nail body 10, a second nail body 20 and a third nail body 30. The second nail body 20 is obliquely arranged at the first end of the first nail body 10. The third nail body 30 is obliquely arranged in the middle of the first nail body 10. The third nail body 30 supports the second nail body 20 so that a triangular area is defined among the first nail body 10, the second nail body 20 and the third nail body 30. The third nail body 30 includes a first nail body segment 31 and a second nail body segment 32 movably matched with the first nail body segment 31, a first end of the first nail body segment 31 supports the second nail body 20, the second nail body segment 32 is arranged in the middle of the first nail body 10 in a penetrating manner, and a buffer cylinder 40 is arranged between a second end of the first nail body segment 31 and a first end of the second nail body segment 32.

With the technical solution of the present embodiment, the third nail body 30 includes a first nail body segment 31 and a second nail body segment 32 movably engaged with the first nail body segment 31, a first end of the first nail body segment 31 supports the second nail body 20, the second nail body segment 32 is inserted into a middle portion of the first nail body 10, and a cushion cylinder 40 is disposed between a second end of the first nail body segment 31 and a first end of the second nail body segment 32. The intramedullary nail device is implanted into the femur, the first nail body is driven in, the second nail body is arranged at the first end of the first nail body in a penetrating mode, the fracture end is pressurized through the second nail body, the third nail body is arranged in the middle of the first nail body in a penetrating mode, and the third nail body supports the second nail body. After implanting the intramedullary nail device, the first end pressurized of first nail body section, cushion cylinder 40 pressurized between the second end of first nail body section and the first end of second nail body section is in the withdrawal state, and produce the damping force to first nail body section, the second end of first nail body section is close to for the first end of second nail body section gradually, make the holistic length of third nail body 30 diminish gradually, the pressure energy that the intramedullary nail device bore is stored and the dispersion by cushion cylinder 40, through the withdrawal relaxation of cushion cylinder 40 and weaken the load that the intramedullary nail device bore in the twinkling of an eye, the elastic modulus of intramedullary nail device has been reduced, stress shielding has been reduced. Therefore, the 'ward triangle' can be effectively reconstructed, the stably supported intramedullary nail device can be 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 device 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 middle of the first nail body 10 is located at a position intermediate between the first end of the first nail body 10 and the second end of the first nail body 10. The second nail body 20 of the present embodiment supports mainly the tension trabecular bone in the femur, and the third nail body 30 supports mainly the tension trabecular bone in the femur.

As shown in fig. 6 to 9, the cushion cylinder 40 includes a cylinder body 41 and a piston rod 42 provided through the cylinder body 41, the piston rod 42 being provided on the second end of the first nail body section 31, and the cylinder body 41 being provided on the first end of the second nail body section 32. In the present embodiment, the buffer medium in the cylinder 41 is oil or gas. When the first end of the first nail body section is pressed and the second end of the first nail body section 31 moves relative to the first end of the second nail body section, the piston rod 42 at the second end of the first nail body section 31 compresses the buffer medium in the cylinder 41, the buffer medium buffers the piston rod 42, and the damping force is effectively generated on the first nail body section.

In an embodiment not shown in the figures, the damping cylinder comprises a cylinder body arranged on the second end of the first nail body section and a piston rod arranged on the first end of the second nail body section.

As shown in fig. 4 to 8, in the process of inserting the third nail body 30 into the middle of the first nail body 10 and screwing the third nail body into the femur, in order to prevent the second nail body 32 and the first nail body 31 from rotating relatively, a first rotation stopping portion is provided on a side wall of the second end of the first nail body 31 on which the piston rod 42 is provided, and a second rotation stopping portion engaged with the first rotation stopping portion is provided on a side wall of the cylinder 41. Like this, through the cooperation of second rotation stopping portion and first rotation stopping portion rotation stopping, when screwing in second nail section 32, first nail section 31 can rotate along with second nail section 32 to make the third nail body 30 can wear to establish the middle part at first nail body 10, and make the first end of first nail body 31 support second nail body 20.

In an embodiment not shown in the drawings, a first rotation stopping portion is disposed on a side wall of the first end of the second nail body segment, where the piston rod may be disposed, and a second rotation stopping portion engaged with the first rotation stopping portion is disposed on a side wall of the cylinder body.

As shown in fig. 6 to 9, the piston rod 42 is disposed on an end surface of the second end of the first nail body section 31, the cylinder 41 is disposed on the second end of the first nail body section 31, and the second end of the first nail body section 31 is fitted over the cylinder 41. Thus, the bore at the second end of the first nail section 31 is in guiding engagement with the cylinder 41 so that the cylinder 41 can move along the axis of the second end of the first nail section 31, preventing the cylinder 41 from being positionally skewed during movement. The first rotation stop comprises an axial groove 34 provided on the inner wall of the second end of the first nail body section 31 and the second rotation stop comprises an axial rib 35 in bayonet fitting engagement with the axial groove 34. Thus, when the first nail body segment 31 is forced and moves relative to the second nail body segment 32, the axial ribs 35 can move within the axial grooves 34 to provide a guiding function, and at the same time, the groove sidewalls of the axial grooves 34 contact the sidewalls of the axial ribs 35 to prevent the first nail body segment 31 from rotating relative to the second nail body segment 32.

As shown in fig. 6 to 9, the axial grooves 34 are four at intervals in the circumferential direction of the second end of the first nail body segment 31, the axial ribs 35 are four at intervals in the circumferential direction of the first end of the second nail body segment 32, and the four axial grooves 34 are provided in one-to-one correspondence with the four axial ribs 35. This allows the third shank 30 to have sufficient structural strength to ensure structural stability of the third shank 30 when the second shank segment 32 is twisted about the first shank segment 31. The number of axial grooves 34 and axial ribs 35 may not be limited to four, but may also be one, two, three, five or more.

As shown in fig. 4 and 6, the piston rod 42 includes a piston 421 located in the cylinder 41 and a rod 422 connected to the piston 421, the rod 422 is inserted into the mounting hole of the cylinder 41, and the intramedullary nail device further includes a sealing member disposed between the rod 422 and the mounting hole. The sealing member can seal between the rod body 422 and the mounting hole, and ensures that the buffer medium cannot leak out from between the rod body 422 and the mounting hole.

As shown in fig. 4, 6 and 9, in the present embodiment, the buffer medium in the cylinder 41 is oil, the piston 421 partitions the inner cavity of the cylinder 41 to form a first chamber and a second chamber, and the piston 421 is provided with an overflowing hole 4211 communicating the first chamber and the second chamber. After the first end of the first nail body segment is pressed, oil in the first cavity flows to the second cavity through the flow hole 4211, at this time, friction between the cavity wall of the inner cavity of the cylinder body 41 and the oil and internal friction between oil molecules form damping force on vibration, and conversion of kinetic energy is achieved, so that the kinetic energy of the buffer cylinder 40 is converted into oil heat, loads borne by the buffer cylinder 40 in the moment are relieved and weakened, and stress borne by the intramedullary nail device can be well reduced by the third nail body 30.

As shown in fig. 3-6, the intramedullary nail device further comprises an elastic member 60 disposed between the second end of the first nail body segment 31 and the first end of the second nail body segment 32. When the first end of the first nail body section is pressed, the pressure can overcome the elasticity of the elastic part 60, in the process that the second end of the first nail body section 31 moves relative to the first end of the second nail body section, the elastic part 60 and the buffer cylinder 40 provide damping force at the same time, the load instantaneously borne by the intramedullary nail device is effectively relaxed and weakened, the pressure energy borne by the intramedullary nail device is stored and dispersed by the buffer cylinder 40 and the elastic part 60, the possibility of stress concentration of the intramedullary nail device is effectively reduced, and the service life of the intramedullary nail device is prolonged. When the first end of the first nail body segment is not pressed or after the pressure disappears, the elastic member 60 applies an elastic force to the second end of the first nail body segment 31 in a direction away from the first end of the second nail body segment 32, the elastic force drives the first end of the first nail body segment to move in a direction away from the first end of the second nail body segment 32, at this time, the cushion cylinder 40 between the second end of the first nail body segment and the first end of the second nail body segment is not pressed and is in an extended state, that is, the second end of the first nail body segment 31 is gradually away from the first end of the second nail body segment, and the oil in the second cavity flows back to the first cavity through the overflowing hole 4211, so that the third nail body 30 is in an initial state of being not pressed.

As shown in fig. 6-9, a cylinder 41 is disposed on a first end of the second nail section 32, and axial ribs 35 are disposed on the ends of the cylinder 41. The intramedullary nail device further comprises an elastic member 60 arranged between the second end of the first nail body section 31 and the first end of the second nail body section 32, the elastic member 60 comprising a spring arranged around the cylinder 41, the spring being located between the axial rib 35 and the first end of the second nail body section 32. The axial rib 35 and the second nail section 32 each limit one end of the spring, defining the range of movement of the spring outside the cylinder 41, preventing the spring from coming out of the cylinder 41. The spring has simple structure and lower installation and design cost. When the first end of the first nail body segment is pressed, the pressure can overcome the elasticity of the elastic element 60, and in the process that the second end of the first nail body segment 31 moves relative to the first end of the second nail body segment, the second end of the first nail body segment 31 pushes the spring, and can be pressed by the second end of the first nail body segment 31 and the first end of the second nail body segment 32, so that the spring is compressed.

The embodiment slows down and weakens the instant load borne by the intramedullary nail device through the movement of the elastic part 60 and the buffer cylinder, so that the third nail body 30 can provide certain elastic support, the intramedullary nail device has elasticity, the possibility of stress concentration of the intramedullary nail device is effectively reduced, and the service life of the intramedullary nail device is prolonged. In particular, the intramedullary nail device is located at a proximal position of the femur 4, i.e. proximal femur.

For ease of connection, machining and assembly, the piston rod 42 and the first nail body section 31 are of a separate construction and are connected by welding, gluing or screwing. To facilitate connection, machining and assembly, the cylinder 41 and the second nail body section 32 are of a separate structure and are connected by welding, bonding or screwing.

In this embodiment, the instantaneous load of the intramedullary nail device is effectively relieved and weakened by the retraction of the buffer cylinder 40 and the compression of the elastic member 60, so that the third nail body 30 can provide a certain elastic support, and the intramedullary nail device has elasticity, thereby effectively reducing the possibility of stress concentration of the intramedullary nail device. In particular, the intramedullary nail device is located at a proximal position of the femur 4, i.e. proximal to the femur.

As shown in fig. 2 to 4, the first nail body segment 31 includes a first polished rod segment 311 and a first threaded segment 312 connected to the first polished rod segment 311, the piston rod 42 is connected to the first polished rod segment 311, and the first threaded segment 312 supports the second nail body 20. In this way, the provision of the first threaded section 312 facilitates screwing of the first nail body section 31 into the femur and enables supporting of the second nail body 20, providing the first nail body section 31 with reliable implantation stability. The arrangement of the first polished rod segment 311 can reduce the resistance generated in the process of screwing the first nail segment 31 into the femur, and can enable the first nail segment 31 to be smoothly screwed into the position where the first thread segment 312 supports the second nail body 20. The second nail body segment 32 comprises a second polished rod segment 321, a third polished rod segment 322 and a second threaded segment 323 connected between the second polished rod segment 321 and the third polished rod segment 322, the outer diameter of the second polished rod segment 321 is smaller than the outer diameter of the outer wall of the third polished rod segment 322, the cylinder 41 is connected with the second polished rod segment 321, and the end of the third polished rod segment 322 provided with the operation hole 3221 forms the second end of the second nail body segment 32. In this way, the second thread section 323 is provided to facilitate the connection of the second nail body segment 32 to the first nail body 10, and the second polished rod segment 321 and the third polished rod segment 322 are provided to reduce the resistance generated in the process of screwing the second nail body segment 32 into the femur, so that the second nail body segment 32 can be smoothly screwed into the position where the second nail body segment 32 is inserted into the middle of the first nail body 10. The operation hole 3221 is disposed to drive the third 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 nail segment 32 to rotate, so that the third nail body 30 can achieve the effect of resetting and pressurizing the fractured bone.

As shown in fig. 2 to 4, the first end of the second shank 20 is provided with an external thread 21, the second end of the second shank 20 is provided with an operation slot 22, and the first end of the first shank section 31 supports the external thread 21. The external thread 21 is arranged to facilitate the screwing of the second nail body 20 into the femur, and the operation slot 22 is arranged to facilitate the operation. The first thread section 312 supports the external thread 21, so that the engagement locking can be performed, and the supporting effect of the third nail body 30 is improved. After the second nail body 20 is implanted into the femur 4, the second end of the second nail body 20 can be exposed out of the outer side wall of the femur 4, so that the operating slot 22 on the second end of the second nail body 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. 4 and 11, the external thread 21 includes a rod body portion and a thread 216 disposed on the rod body portion, and the thread 216 is provided with a plurality of first grooves 201. When the second nail body 20 is stressed, the external thread 21 of the second nail body 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 assembly is reduced, the screw teeth 216 can adapt to the surrounding bone substances, 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 nail body 20 can be effectively prevented from penetrating out of the femur.

As shown in fig. 4 and 11, when the external thread 21 of the second nail body 20 is screwed in, the bone in the femur is compressed, because the plurality of first grooves 201 on the same circle of the screw teeth 216 are radially arranged, each first groove 201 is adapted to the embedded bone, and the radially arranged plurality of first grooves 201 can engage more bone while reducing the elastic modulus of the second nail body 20, so that the screw teeth 216 can effectively adapt to the surrounding bone.

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. 4 and 11, the height of the thread 216 of the external thread 21 is gradually reduced from the distance from the first nail body 10 to the proximity of the first nail body 10. In this way, the part of the screw thread 216 of the external thread 21 far from the first nail body 10 is higher and embedded deeper into the bone, so that the bone can be bitten, and meanwhile, because the part of the screw thread 216 of the external thread 21 near the first nail body 10 is lower and has higher strength, the part of the screw thread 216 far from the first nail body 10 can be provided with enough strength.

As shown in fig. 4 and 11, 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 23. In this way, in the process of compressing the bone in the femur when the external thread 21 of the second nail body 20 is screwed in, because the first rod body 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 211 can be screwed into deeper bone, and more bone can be simultaneously allowed to be embedded into the first grooves 201 and the second grooves 23, so that the elastic modulus of the second nail body 20 is closer to that of the bone, the self-adaptation condition of the screw teeth 216 and the surrounding bone is satisfied, and the bone cutting and the second nail body 20 can be further prevented from penetrating out of the femur 4.

As shown in fig. 4 and 11, in order to achieve better snap-locking of the screw teeth 216 on the rod body portion, the axial dimension of the first rod body portion 211 is larger than the axial dimension of the second rod body portion 212. The first lever part 211 is provided with a first stopping groove 213, the second lever part 212 is provided with a second stopping groove 214 communicated with the first stopping groove 213, and the ends of the first thread section 312 are positioned in the first stopping groove 213 and the second stopping groove 214. The first stopping groove 213 and the second stopping groove 214 respectively limit both sides of the end of the third nail body 30, and prevent the third nail body 30 from being dislocated when supporting the second nail body 20, so that the third nail body 30 is reliably in the supporting position.

As shown in fig. 2 to 4 and 10, the first nail body 10 includes a third nail body segment 11 and a fourth nail body segment 12 connected to the third nail body segment 11, an outer diameter of the third nail body segment 11 is larger than an outer diameter of the fourth nail body segment 12, the second nail body 20 is inserted through a first end of the third nail body segment 11, and a first end of the second nail body segment 32 and a second end of the second nail body segment 32 are respectively located on both sides of a second end of the third nail body segment 11. Thus, the third polished rod section 322 has a longer length, so that after the third nail body 30 is implanted in the femur 4, the second end of the third polished rod section 322 can be exposed out of the outer side wall of the femur 4, so that the operation hole 3221 on the third polished rod section 322 can also be exposed out of the femur 4. And because the outer diameter of the third nail body section is larger than that of the fourth nail body section, the third nail body section has enough structural strength, and the installation position of the second nail body 20 and the installation position of the third nail body 30 are convenient to arrange on the third nail body section. The intramedullary nail device further comprises a transverse nail 50 disposed through the fourth nail body section 12. The provision of the transverse nail 50 facilitates locking of the fourth nail body section 12 into the femur, improving the stability of the overall structure of the intramedullary nail device. The first nail body 10, the second nail body 20, the third nail body 30 and the transverse nail 50 of the present embodiment are all preferably made of medical titanium alloy materials.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific 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 … …", "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 the terms have no special meanings unless otherwise stated, 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 device, comprising:

a first nail body (10);

the second nail body (20) is obliquely arranged at the first end of the first nail body (10) in a penetrating way;

a third nail body (30) obliquely penetrating the middle of the first nail body (10), wherein the third nail body (30) supports the second nail body (20) so that a triangular area is defined among the first nail body (10), the second nail body (20) and the third nail body (30),

the third nail body (30) comprises a first nail body section (31) and a second nail body section (32) movably matched with the first nail body section (31), the first end of the first nail body section (31) supports the second nail body (20), the second nail body section (32) penetrates through the middle of the first nail body (10), and a buffer cylinder (40) is arranged between the second end of the first nail body section (31) and the first end of the second nail body section (32).

2. The intramedullary nail device according to claim 1, wherein the dampening cylinder (40) comprises a cylinder body (41) and a piston rod (42) threaded on the cylinder body (41), one of the piston rod (42) and the cylinder body (41) being disposed on the second end of the first nail body segment (31) and the other being disposed on the first end of the second nail body segment (32).

3. Intramedullary nail device according to claim 2, characterized in that a first rotation stop is provided on the side wall of the second end of the first nail body segment (31) or the side wall of the first end of the second nail body segment (32) provided with the piston rod (42), and a second rotation stop cooperating with the first rotation stop is provided on the side wall of the cylinder (41).

4. The intramedullary nail device according to claim 3, wherein the piston rod (42) is arranged on an end face of the second end of the first nail body section (31), the cylinder (41) is arranged on the second end of the first nail body section (31), the second end of the first nail body section (31) is sleeved outside the cylinder (41), the first rotation stop portion comprises an axial groove (34) arranged on an inner wall of the second end of the first nail body section (31), and the second rotation stop portion comprises an axial rib (35) in plug-fit engagement with the axial groove (34).

5. The intramedullary nail device according to claim 2, characterized in that the piston rod (42) comprises a piston (421) located inside the cylinder (41) and a rod body (422) connected to the piston (421), the rod body (422) being arranged through a mounting hole of the cylinder (41), the intramedullary nail device further comprising a seal arranged between the rod body (422) and the mounting hole.

6. The intramedullary nail device according to claim 5, characterized in that the piston (421) divides the inner cavity of the cylinder (41) to form a first chamber and a second chamber, and an overflowing hole (4211) communicating the first chamber and the second chamber is arranged on the piston (421).

7. The intramedullary nail device according to claim 1, further comprising a spring (60) disposed between the second end of the first nail body segment (31) and the first end of the second nail body segment (32).

8. The intramedullary nail device of claim 4,

the cylinder (41) being arranged on a first end of the second nail body section (32), the axial ribs (35) being arranged at an end of the cylinder (41), the intramedullary nail device further comprising an elastic member (60) arranged between a second end of the first nail body section (31) and the first end of the second nail body section (32), the elastic member (60) comprising a spring arranged outside the cylinder (41), the spring being located between the axial ribs (35) and the first end of the second nail body section (32);

the piston rod (42) and the first nail body section (31) are of a split structure and are connected through welding, bonding or screwing, and the cylinder body (41) and the second nail body section (32) are of a split structure and are connected through welding, bonding or screwing.

9. The intramedullary nail device of claim 2,

the first nail body section (31) comprises a first polished rod section (311) and a first thread section (312) connected with the first polished rod section (311), the piston rod (42) is connected with the first polished rod section (311), and the first thread section (312) supports the second nail body (20);

the second nail body segment (32) comprises a second polished rod segment (321), a third polished rod segment (322) and a second threaded section (323) connected between the second polished rod segment (321) and the third polished rod segment (322), the outer diameter of the second polished rod segment (321) is smaller than the outer diameter of the outer wall of the third polished rod segment (322), the cylinder (41) is connected with the second polished rod segment (321), and the end, provided with an operation hole (3221), of the third polished rod segment (322) forms the second end of the second nail body segment (32).

10. The intramedullary nail device of claim 1,

a first end of the second nail body (20) is provided with an external thread (21), a second end of the second nail body (20) is provided with an operation groove (22), and a first end of the first nail body section (31) supports the external thread (21);

the first nail body (10) comprises a third nail body section (11) and a fourth nail body section (12) connected with the third nail body section (11), the outer diameter of the third nail body section (11) is larger than that of the fourth nail body section (12), the second nail body (20) penetrates through the first end of the third nail body section (11), and the first end of the second nail body section (32) and the second end of the second nail body section (32) are located on two sides of the second end of the third nail body section (11) respectively;

the intramedullary nail device further comprises a transverse nail (50) threaded onto the fourth nail body section (12).

Images