CN114081605A - Intramedullary nail assembly - Google Patents

Abstract

The present invention provides an intramedullary nail assembly comprising: a main nail; the first auxiliary nail penetrates through the first end of the main nail, and the axis of the first auxiliary nail is obliquely arranged relative to the axis of the main nail; the supplementary nail of second wears to establish in the middle part of main nail, the axis of the supplementary nail of second sets up for the axis slope of main nail, the supplementary nail of second supports first supplementary nail to make and prescribe a limit to triangle-shaped region between main nail, first supplementary nail and the supplementary nail of second, wherein, the supplementary nail of second includes first nail section and with the portable complex second nail section of first nail section, first supplementary nail is supported to the first end of first nail section, the middle part at main nail is worn to establish by the second nail section, be provided with elastic buffer between the second end of first nail section and the first end of second 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 assembly

Technical Field

The invention relates to the field of medical instruments, in particular to an intramedullary nail assembly.

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 unstable intertrochanteric fracture of femur, currently, intramedullary nail fixation is advocated, the intramedullary nail is fixed by an intramedullary nail, the intramedullary nail passes through a femoral medullary cavity, the eccentric distance is relatively short and is closer to a lower limb mechanical shaft, the probability of internal fixation failure after operation is relatively small compared with the probability of external fixation, the intramedullary nail is placed in the intramedullary nail, the connection of fracture parts between the femoral intertrochanteric is rebuilt, the physiological structural integrity of the fracture parts is recovered, the fracture healing is promoted, the complications caused by long-term lying in bed are reduced, the death rate is reduced, and the limb function of a patient is recovered after the fracture healing. At present, various types of femoral intramedullary nails (such as the femoral intramedullary nail device disclosed in the application publication No. CN105395244A of the Chinese invention patent application) are widely applied to unstable intertrochanteric fractures, and in the clinical application process, the existing femoral intramedullary nail device for treating unstable intertrochanteric fractures still has a high internal fixation failure rate.

Studies have shown that the medial 1, lateral 2 and superior 3 lateral walls of the proximal femur, as shown in fig. 1, are important structural bases for maintaining the proximal femur stable. The structure is equivalent to the inner side, the outer side and the upper side of a mechanical triangle (a 'ward triangle') in theoretical mechanical analysis. Each side has the following mechanical effects in maintaining the stability of the proximal structure of the femur: the inner side of the thighbone forms an oblique support of a thighbone near-end cantilever beam structure, so that the bending stress and deflection of the structure are greatly reduced; the outer side edge can effectively weaken the sliding and deflection of the femoral neck under physiological load, thereby realizing the stability of the fracture end; and the upper side is connected with the inner side and the outer side, so that the bending moment generated by physiological load is resisted by the inner structure and the outer structure of the proximal end of the femur. 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-like structure is formed after an intramedullary nail operation, when unstable femoral intertrochanteric fracture is treated, stress of bone tissues bearing load is completely replaced, stress shielding of an internal fixation angulation part is realized, and the performance of resisting external and lower oblique shearing force is poor. On the aspect of structural design, the existing intramedullary nail does not attach importance to the composite structure of the tension arm of the pressure trabecula and the tension arm of the tension trabecula in the proximal intertrochanteric part of the normal femur, the bones of the femoral head and the neck to replace reconstruction, and the importance of the 'ward triangle' stable support structure formed by the tension trabecula and the pressure trabecula is ignored. The stability of the triangular support structure formed by the normal bone tissue is far superior to the lever-like structure formed by replacing the normal structure by internal fixation. Meanwhile, the intramedullary nails are rigid structures, and the femoral system made of metal materials has too high elastic modulus for bone substances, generates stress shielding in the compression process, and is very easy to cause the conditions that the internally implanted intramedullary nail is cut out of the femur or the internal fixation fails.

Disclosure of Invention

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

To achieve the above object, the present invention provides an intramedullary nail assembly comprising: a main nail; the first auxiliary nail penetrates through the first end of the main nail, and the axis of the first auxiliary nail is obliquely arranged relative to the axis of the main nail; the supplementary nail of second wears to establish in the middle part of main nail, the axis of the supplementary nail of second sets up for the axis slope of main nail, the supplementary nail of second supports first supplementary nail to make and prescribe a limit to triangle-shaped region between main nail, first supplementary nail and the supplementary nail of second, wherein, the supplementary nail of second includes first nail section and with the portable complex second nail section of first nail section, first supplementary nail is supported to the first end of first nail section, the middle part at main nail is worn to establish by the second nail section, be provided with elastic buffer between the second end of first nail section and the first end of second nail section.

Further, the elastic buffer comprises an air pocket.

Furthermore, one of the second end of the first nail section and the first end of the second nail section is provided with an accommodating cylinder for accommodating the air bag, and the other one is provided with a butting part which is opposite to the opening part of the accommodating cylinder and is in extrusion fit with the air bag.

Furthermore, a first rotation stopping portion is arranged on the outer wall of the accommodating cylinder, a second rotation stopping portion located on the side portion of the abutting portion is further arranged at the second end of the first nail section or the first end of the second nail section, and the second rotation stopping portion is matched with the first 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 groove is a plurality of along holding a plurality of that the circumference interval set up of section of thick bamboo, and the axial rib is a plurality of along the circumference interval setting of the first end of second nail section, and a plurality of axial grooves set up with a plurality of axial ribs one-to-one.

Furthermore, the accommodating cylinder is arranged at the second end of the first nail section, a limiting groove section is arranged between the accommodating cylinder and the second end of the first nail section, the axial rib is arranged at the first end of the second nail section, a limiting ring is arranged at the end part of the axial rib, and the limiting ring is movably arranged in the limiting groove section along the axial direction of the first nail section so as to enable the abutting part to extrude or release the air bag; and/or the limiting ring and the axial rib are of split structures and are connected through welding, bonding or screwing, and the accommodating cylinder and the first nail section are of split structures and are connected through welding, bonding or screwing.

Further, the first nail section comprises a first polished rod section and a first thread section connected with the first polished rod section, the containing cylinder is connected with the first polished rod section, and the first thread section supports the first auxiliary nail.

Furthermore, the second nail 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 abutting part is arranged on the end face of the second polished rod section, and the end, provided with the operation hole, of the third polished rod section forms a second end of the second nail section.

Further, the first end of the first auxiliary nail is provided with an external thread, the second end of the first auxiliary nail is provided with an operation groove, and the first end of the first nail section supports the external thread.

Furthermore, the main nail comprises a third nail section and a fourth nail section connected with the third nail section, the outer diameter of the third nail section is larger than that of the fourth nail section, the first auxiliary nail penetrates through the first end of the third nail section, and the first end of the second nail section and the second end of the second nail section are respectively positioned on two sides of the second end of the third nail section; and/or, the intramedullary nail assembly further comprises a transverse nail arranged on the fourth nail section in a penetrating way.

By applying the technical scheme of the invention, the intramedullary nail component comprises: the main nail, the first auxiliary nail and the second auxiliary nail. The first auxiliary nail penetrates through the first end of the main nail, and the axis of the first auxiliary nail is obliquely arranged relative to the axis of the main nail. The second auxiliary nail penetrates through the middle of the main nail, the axis of the second auxiliary nail is obliquely arranged relative to the axis of the main nail, and the second auxiliary nail supports the first auxiliary nail so that a triangular area is defined among the main nail, the first auxiliary nail and the second auxiliary nail. Wherein, the supplementary nail of second includes first nail section and with the first movable complex second nail section of nail section, the first end support first supplementary nail of first nail section, the middle part at the main nail is worn to establish by the second nail section, is provided with elastic buffer between the second end of first nail section and the first end of second nail section. The intramedullary nail subassembly is implanted the in-process in the thighbone, squeezes into the main nail, and first supplementary nail is worn to establish the first end at the main nail, through the pressurization of first supplementary nail to the fracture end, and the middle part at the main nail is worn to establish by the supplementary nail of second, and the supplementary nail of second supports first supplementary nail. After implanting the intramedullary nail subassembly, the first end pressurized of first nail section, elastic buffer pressurized between the second end of first nail section and the first end of second nail section is in compression state, the second end of first nail section is close to for the first end of second nail section gradually, make the holistic length of the supplementary nail of second diminish gradually, the pressure energy that the intramedullary nail subassembly bore is stored and the dispersion by elastic buffer, the deformation through elastic buffer comes to slow down and weakens the load that the intramedullary nail subassembly bore in the twinkling of an eye, the elastic modulus of intramedullary nail subassembly has been reduced, stress shielding has been reduced. Therefore, the 'ward triangle' can be effectively reconstructed, the stably supported intramedullary nail component is realized, effective restoration and fixation of the femoral head of a patient can be well realized, the 'ward triangle' of the femoral trochanter part can be reconstructed, the stress borne by the femur can be better dispersed, and the intramedullary nail component 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 invention and, together with the description, serve to explain the invention and not to limit the invention. 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 assembly implanted within a femur according to an embodiment of the intramedullary nail assembly of the present invention;

FIG. 3 illustrates a perspective view of the intramedullary nail assembly of FIG. 2;

FIG. 4 shows a cross-sectional schematic view of the intramedullary nail assembly of FIG. 2;

FIG. 5 is a perspective view of the balloon of the intramedullary nail assembly of FIG. 2 in a compressed state;

FIG. 6 is a perspective view of the balloon of the intramedullary nail assembly of FIG. 2 in an expanded state;

FIG. 7 is an exploded schematic view of a second auxiliary nail of the intramedullary nail assembly of FIG. 2;

FIG. 8 is an exploded, schematic angular view of a second auxiliary nail of the intramedullary nail assembly of FIG. 2; and

fig. 9 shows a front schematic view of a primary nail of the intramedullary nail assembly of fig. 2;

fig. 10 shows a front view schematic of a first auxiliary nail of the intramedullary nail assembly 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 main nail; 11. a third nail section; 12. a fourth nail section; 20. a first auxiliary nail; 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 second auxiliary nail; 31. a first nail section; 311. a first polished rod segment; 312. a first thread segment; 32. a second nail section; 321. a second polished rod segment; 322. a third polished rod segment; 3221. an operation hole; 323. a second thread segment; 33. a receiving cylinder; 34. a butting part; 35. an axial slot; 36. axial ribs; 37. a limiting groove section; 38. a limiting ring; 40. an air bag; 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 invention, 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, further discussion thereof is not required in subsequent figures.

As shown in fig. 2 to 6 and 9, the intramedullary nail assembly of the present embodiment includes: a main nail 10, a first auxiliary nail 20, and a second auxiliary nail 30. The first auxiliary nail 20 is arranged at the first end of the main nail 10, and the axis of the first auxiliary nail 20 is obliquely arranged relative to the axis of the main nail 10. The second auxiliary nail 30 is arranged in the middle of the main nail 10, the axis of the second auxiliary nail 30 is inclined relative to the axis of the main nail 10, and the second auxiliary nail 30 supports the first auxiliary nail 20, so that a triangular area is defined among the main nail 10, the first auxiliary nail 20 and the second auxiliary nail 30. The second auxiliary nail 30 includes a first nail section 31 and a second nail section 32 movably matched with the first nail section 31, the first end of the first nail section 31 supports the first auxiliary nail 20, the second nail section 32 is arranged in the middle of the main nail 10 in a penetrating manner, and an elastic buffer is arranged between the second end of the first nail section 31 and the first end of the second nail section 32.

With the present embodiment, the elastic buffer comprises a balloon 40, and the intramedullary nail assembly comprises: a main nail 10, a first auxiliary nail 20, and a second auxiliary nail 30. The first auxiliary nail 20 is arranged at the first end of the main nail 10, and the axis of the first auxiliary nail 20 is obliquely arranged relative to the axis of the main nail 10. The second auxiliary nail 30 is arranged in the middle of the main nail 10, the axis of the second auxiliary nail 30 is inclined relative to the axis of the main nail 10, and the second auxiliary nail 30 supports the first auxiliary nail 20, so that a triangular area is defined among the main nail 10, the first auxiliary nail 20 and the second auxiliary nail 30. In this way, the main nail 10, the first auxiliary nail 20 and the second auxiliary nail 30 form a triangular support, which can achieve reduction and fixation after the tuberosity fracture and can well reconstruct the biomechanics after the operation. The second auxiliary nail 30 includes a first nail section 31 and a second nail section 32 movably matched with the first nail section 31, the first end of the first nail section 31 supports the first auxiliary nail 20, the second nail section 32 penetrates the middle of the main nail 10, and an air bag 40 is arranged between the second end of the first nail section 31 and the first end of the second nail section 32. In the process of implanting the intramedullary nail component into the femur 4, the main nail 10 is driven, the first auxiliary nail 20 is arranged at the first end of the main nail 10 in a penetrating way, the fracture end is pressurized through the first auxiliary nail 20, the second auxiliary nail 30 is arranged at the middle part of the main nail 10 in a penetrating way, and the second auxiliary nail 30 supports the first auxiliary nail 20. After the intramedullary nail assembly is implanted, the first end of the first nail section 31 is pressed, the air bag 40 between the second end of the first nail section 31 and the first end of the second nail section 32 is pressed to be in a compression state, the second end of the first nail section 31 is gradually close to the first end of the second nail section 32, so that the overall length of the second auxiliary nail 30 is gradually reduced, the pressure energy borne by the intramedullary nail assembly is stored and dispersed by the air bag 40, the load instantaneously borne by the intramedullary nail assembly is relieved and weakened through the deformation of the air bag 40, the elastic modulus of the intramedullary nail assembly is reduced, and the stress shielding is reduced. Therefore, the 'ward triangle' can be effectively reconstructed, the stably supported intramedullary nail component is realized, the effective reduction and fixation of the head of the femur 4 of a patient can be well realized, the 'ward triangle' of the tuberosity part of the femur 4 can be reconstructed, the stress borne by the femur 4 can be better dispersed, and the intramedullary nail component implanted into the femur 4 is prevented from being cut out of the femur 4. 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. The balloon 40 of this embodiment is filled with a gas, and the shape of the balloon 40 is preferably an ellipsoid, similar to a capsule. The outer wall of the balloon 40 is a high-toughness material. The deformation of the air bag 40 is used for relieving and weakening the load instantaneously borne by the intramedullary nail assembly, so that the second auxiliary nail 30 can provide certain elastic support, the intramedullary nail assembly has elasticity, the possibility of stress concentration of the intramedullary nail assembly is effectively reduced, and the service life of the intramedullary nail assembly is prolonged. In particular, the intramedullary nail assembly is located at a proximal position of the femur 4, i.e. proximal to the femur. The high-toughness material is preferably latex.

It should be noted that the middle of the main nail 10 refers to a position located between the first end of the main nail 10 and the second end of the main nail 10. The first auxiliary nail 20 of the present embodiment mainly supports the tension trabecular bone in the femur, and the second auxiliary nail 30 mainly supports the tension trabecular bone in the femur.

It should be noted that the elastic buffer member of this embodiment may include an elastic body or a spring, when the elastic buffer member includes the elastic body, the elastic body is connected between the second end of the first nail section and the first end of the second nail section through an injection molding method or a screw joint, when the elastic buffer member includes the spring, the second end of the first nail section and the first end of the second nail section are in a nested fit, and the spring is located between the second end of the first nail section and the first end of the second nail section.

As shown in fig. 4 to 8, the second end of the first nail section 31 is provided with a receiving cylinder 33 for receiving the air bag 40, and the first end of the second nail section 32 is provided with a butting part 34 opposite to the mouth of the receiving cylinder 33 and press-fitted with the air bag 40. The accommodation barrel 33 is provided to facilitate the second auxiliary nail 30 to accommodate the air bag 40, so that the structure of the second auxiliary nail 30 is compact, and at the same time, the abutting portion 34 presses the air bag 40, so that the air bag 40 can be switched from the expanded state to the compressed state. The abutment portion 34 may be an abutment table or an abutment post.

In an embodiment not shown in the drawings, an accommodating barrel for accommodating the air bag may be arranged in the first end of the second nail section, and an abutting portion which is opposite to the mouth of the accommodating barrel and is in press fit with the air bag may be arranged on the second end of the first nail section.

As shown in fig. 4 to 8, in the process of inserting the second auxiliary nail 30 into the middle of the main nail 10 and screwing the second auxiliary nail into the femur, in order to prevent the second nail section 32 and the first nail section 31 from rotating relatively, the first rotation stopping portion on the outer wall of the accommodating barrel 33, the first end of the second nail section 32 of the first nail section 31 is further provided with a second rotation stopping portion located at the side of the abutting portion 34, and the second rotation stopping portion is in rotation stopping fit with the first rotation stopping portion. Like this, through the cooperation of the second portion of splining and the first portion of splining, when the screw-in second nail section 32, first nail section 31 can rotate along with second nail section 32 to make the supplementary nail 30 of second wear to establish in the middle part of main nail 10, and make the first end of first nail section 31 support first supplementary nail 20.

In an embodiment not shown in the drawings, an accommodating barrel for accommodating the airbag may be disposed in the first end of the second nail section, the first rotation stopping portion may be disposed on an outer wall of the accommodating barrel, a butting portion opposite to the mouth portion of the accommodating barrel and press-fitted with the airbag may be disposed on the second end of the first nail section, and a second rotation stopping portion located at a side portion of the butting portion may be disposed on the second end of the first nail section.

As shown in fig. 5 to 8, the first rotation-stopping portion includes an axial groove 35, and the second rotation-stopping portion includes an axial rib 36 engaged with the axial groove 35, so that when the first nail section 31 is stressed and moves relative to the second nail section 32, the axial rib 36 can move in the axial groove 35 to play a guiding role, and meanwhile, the groove side wall of the axial groove 35 contacts with the side wall of the axial rib 36 to prevent the first nail section 31 from rotating relative to the second nail section 32.

As shown in fig. 5 to 8, the axial grooves 35 are four grooves spaced apart in the circumferential direction of the accommodating cylinder 33, the axial ribs 36 are four grooves spaced apart in the circumferential direction of the first end of the second nail section 32, and the four axial grooves 35 and the four axial ribs 36 are provided in one-to-one correspondence. Thus, when the second nail section 32 twists the first nail section 31, the second auxiliary nail 30 has enough structural strength, and the structural stability of the second auxiliary nail 30 can be ensured. 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.

In particular, the radial section of the axial ribs 36 along the second nail section 32 is preferably semicircular, and the axial grooves 35 corresponding to the axial ribs 36 are arc-shaped grooves. Thus, the axial beads 36 move axially in the axial grooves 35 more smoothly.

As shown in fig. 5 to 8, the accommodating cylinder 33 is disposed at the second end of the first nail section 31, a limiting groove section 37 is disposed between the accommodating cylinder 33 and the second end of the first nail section 31, the axial rib 36 is disposed at the first end of the second nail section 32, a limiting ring 38 is disposed at an end of the axial rib 36, and the limiting ring 38 is movably disposed in the limiting groove section 37 along the axial direction of the first nail section 31, so that the abutting portion 34 presses or releases the airbag 40. The limiting ring 38 is located in the limiting groove section 37 and can limit the moving range of the first nail section 31 relative to the second nail section 32, and the first nail section 31 and the second nail section 32 are prevented from being disengaged. Specifically, in the process that the first nail section 31 moves relative to the second nail section 32, when the limit ring 38 abuts against the side wall of the limit groove section 37 close to the first end of the first nail section 31, the abutting part 34 presses the airbag 40 to enable the airbag 40 to be in a compressed state, and when the limit ring 38 abuts against the side wall of the limit groove section 37 far away from the first end of the first nail section 31, the abutting part 34 releases the airbag 40 to enable the airbag 40 to be in an expanded state.

In order to facilitate connection, processing and assembly, the limiting ring 38 and the axial rib 36 are of a split structure and are connected by welding, bonding or screwing, and the accommodating barrel 33 and the first nail section 31 are of a split structure and are connected by welding, bonding or screwing.

In an embodiment not shown in the drawings, the accommodating cylinder may be disposed on the second end of the first nail section, a limiting groove section is disposed between the accommodating cylinder and the second end of the first nail section, the axial rib is disposed on the first end of the second nail section, a limiting ring is disposed at an end portion of the axial rib, and the limiting ring is movably disposed in the limiting groove section along the axial direction of the first nail section so that the abutting portion extrudes or releases the airbag; or the limiting ring and the axial rib are of split structures and are connected through welding, bonding or screwing, and the containing cylinder and the first nail section are of split structures and are connected through welding, bonding or screwing.

As shown in fig. 4 to 6, the first nail section 31 includes a first polished rod section 311 and a first thread section 312 connected to the first polished rod section 311, the accommodating barrel 33 is connected to the first polished rod section 311, and the first thread section 312 supports the first auxiliary nail 20. In this way, the arrangement of the first thread section 312 facilitates the screwing of the first nail section 31 into the femur and enables the first auxiliary nail 20 to be supported, ensuring that the first nail section 31 has reliable implantation stability. The first polished rod section 311 can reduce the resistance generated during the process of screwing the first nail section 31 into the femur, and can enable the first nail section 31 to be smoothly screwed into the position where the first threaded section 312 supports the first auxiliary nail 20.

As shown in fig. 4 to 6, the second nail section 32 includes a second polished rod section 321, a third polished rod section 322, and a second threaded section 323 connected between the second polished rod section 321 and the third polished rod section 322, an outer diameter of the second polished rod section 321 is smaller than an outer diameter of an outer wall of the third polished rod section 322, the abutting portion 34 is disposed on an end surface of the second polished rod section 321, and an end of the third polished rod section 322, at which the operating hole 3221 is disposed, forms a second end of the second nail section 32. Like this, the setting of second screw thread section 323 is convenient for second nail section 32 to connect on main nail 10, and the setting of second polished rod section 321 and third polished rod section 322 can reduce the resistance that second nail section 32 twists the in-process production to the thighbone, can make second nail section 32 smoothly twist to the position that second nail section 32 wore to establish at the middle part of main nail 10. The operation hole 3221 is configured 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 second auxiliary nail 30 can achieve a reduction and pressurization effect on the fractured end.

As shown in fig. 3 and 4, a first end of the first auxiliary nail 20 is provided with an external thread 21, a second end of the first auxiliary nail 20 is provided with an operation groove 22, and a first end of the first nail section 31 supports the external thread 21. The arrangement of the external thread 21 facilitates the screwing of the first auxiliary nail 20 into the femur, and the arrangement of the operation slot 22 facilitates the operation. The first thread section 312 supports the external thread 21, so that the snap locking can be performed, and the supporting effect of the second auxiliary nail 30 is improved. After the first auxiliary nail 20 is implanted in the femur 4, the second end of the first auxiliary 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 first auxiliary 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. 4 and 10, the external thread 21 includes a rod body and a thread 216 disposed on the rod body, and the thread 216 is provided with a plurality of first grooves 201. When the first auxiliary nail 20 is stressed, the external thread 21 of the first auxiliary 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 first auxiliary nail 20 can be effectively prevented from penetrating out of the femur.

As shown in fig. 4 and 10, when the external thread 21 of the first auxiliary nail 20 is screwed in, the bone substance 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 substance, and the radially arranged plurality of first grooves 201 can bite more bone substances while reducing the elastic modulus of the first auxiliary nail 20, so that the screw teeth 216 can effectively adapt to the surrounding bone substances.

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 10, the height of the thread 216 of the external thread 21 is gradually reduced from a direction away from the main nail 10 to a direction close to the main nail 10. Thus, the portion of the thread 216 of the external thread 21 which is far from the main nail 10 is higher and deeper embedded into the bone, so that the bone can be gripped, and at the same time, since the portion of the thread 216 of the external thread 21 which is near to the main nail 10 is lower and higher in strength, sufficient strength can be provided for the portion of the thread 216 which is far from the main nail 10.

As shown in fig. 4 and 10, 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 substance in the femur when the external thread 21 of the first auxiliary nail 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 a deeper bone substance, and more bone substances can be simultaneously allowed to be embedded into the plurality of first grooves 201 and the plurality of second grooves 23, so that the elastic modulus of the first auxiliary nail 20 is closer to that of the bone substance, the self-adaption condition of the screw teeth 216 and the surrounding bone substances is met, and the bone substance cutting and the first auxiliary nail 20 can be further prevented from penetrating out of the femur 4.

As shown in fig. 4 and 10, 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 and second stopper grooves 213 and 214 respectively restrict both sides of the end portion of the second auxiliary nail 30 to prevent the second auxiliary nail 30 from being misaligned while supporting the first auxiliary nail 20, so that the second auxiliary nail 30 is reliably positioned at the supporting position.

As shown in fig. 2 to 4 and 9, the main nail 10 includes a third nail section 11 and a fourth nail section 12 connected to the third nail section 11, an outer diameter of the third nail section 11 is greater than an outer diameter of the fourth nail section 12, the first auxiliary nail 20 is inserted into a first end of the third nail section 11, and a first end of the second nail section 32 and a second end of the second nail section 32 are respectively located at two sides of a second end of the third nail section 11. Thus, the third polished rod section 322 has a longer length, so that the second end of the third polished rod section 322 can be exposed to the outer sidewall of the femur 4 after the second auxiliary nail 30 is implanted in the femur 4, so that the operation hole 3221 on the third polished rod section 322 can also be exposed to the outside of the femur 4. And because the outer diameter of the third nail section 11 is larger than that of the fourth nail section 12, the third nail section 11 has enough structural strength, and the installation position of the first auxiliary nail 20 and the installation position of the second auxiliary nail 30 are conveniently arranged on the third nail section 11. The intramedullary nail assembly further includes a transverse nail 50 disposed through the fourth nail segment 12. The provision of the transverse nail 50 facilitates locking the fourth nail section 12 into the femur, improving the stability of the overall structure of the intramedullary nail assembly.

In an embodiment not shown in the drawings, the main nail comprises a third nail section and a fourth nail section connected with the third nail section, the outer diameter of the third nail section is larger than that of the fourth nail section, the first auxiliary nail is arranged at the first end of the third nail section in a penetrating mode, and the first end of the second nail section and the second end of the second nail section are located on two sides of the second end of the third nail section respectively. Because the external diameter of third nail section is greater than fourth nail section for the third nail section has sufficient structural strength, is convenient for set up the mounted position of first supplementary nail and the mounted position of the supplementary nail of second on the third nail section. Or the intramedullary nail assembly further comprises a transverse nail arranged on the fourth nail section in a penetrating way. The main nail 10, the first auxiliary nail 20, the second auxiliary nail 30 and the transverse nail 50 of the present embodiment are preferably made of medical titanium alloy material.

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 (11)

1. An intramedullary nail assembly, comprising:

a main nail (10);

the first auxiliary nail (20) is arranged at the first end of the main nail (10) in a penetrating way, and the axis of the first auxiliary nail (20) is obliquely arranged relative to the axis of the main nail (10);

a second auxiliary nail (30) arranged in the middle of the main nail (10), wherein the axis of the second auxiliary nail (30) is inclined relative to the axis of the main nail (10), the second auxiliary nail (30) supports the first auxiliary nail (20) so that a triangular area is defined among the main nail (10), the first auxiliary nail (20) and the second auxiliary nail (30),

wherein, supplementary nail of second (30) include first nail section (31) and with first nail section (31) portable complex second nail section (32), the first end of first nail section (31) supports first supplementary nail (20), second nail section (32) are worn to establish the middle part of main nail (10), the second end of first nail section (31) with be provided with elastic buffer between the first end of second nail section (32).

2. The intramedullary nail assembly of claim 1, wherein the elastomeric bumper comprises a balloon (40).

3. Intramedullary nail assembly according to claim 2, characterized in that one of the second end of the first nail segment (31) and the first end of the second nail segment (32) is provided with a housing cylinder (33) housing the balloon (40), the other is provided with an abutment portion (34) opposite to the mouth of the housing cylinder (33) and press-fitted with the balloon (40).

4. The intramedullary nail assembly according to claim 3, wherein a first rotation stop portion is provided on an outer wall of the receiving cylinder (33), and a second rotation stop portion is provided on a side portion of the abutting portion (34) at the second end of the first nail section (31) or the first end of the second nail section (32), and the second rotation stop portion is engaged with the first rotation stop portion.

5. The intramedullary nail assembly of claim 4, wherein the first rotation stop portion includes an axial slot (35) and the second rotation stop portion includes an axial rib (36) in bayonet engagement with the axial slot (35).

6. The intramedullary nail assembly according to claim 5, wherein the axial grooves (35) are a plurality spaced circumferentially along the receiving cylinder (33), the axial ribs (36) are a plurality spaced circumferentially along the first end of the second nail section (32), and the plurality of axial grooves (35) are disposed in a one-to-one correspondence with the plurality of axial ribs (36).

7. The intramedullary nail assembly of claim 5,

the accommodating barrel (33) is arranged at the second end of the first nail section (31), a limiting groove section (37) is arranged between the accommodating barrel (33) and the second end of the first nail section (31), the axial rib (36) is arranged at the first end of the second nail section (32), a limiting ring (38) is arranged at the end part of the axial rib (36), and the limiting ring (38) is movably arranged in the limiting groove section (37) along the axial direction of the first nail section (31) so as to enable the abutting part (34) to extrude or release the air bag (40); and/or the presence of a gas in the gas,

the limiting ring (38) and the axial ribs (36) are of split structures and are connected through welding, bonding or screwing, and the accommodating cylinder (33) and the first nail section (31) are of split structures and are connected through welding, bonding or screwing.

8. The intramedullary nail assembly according to claim 3, wherein the first nail section (31) comprises a first shank section (311) and a first threaded section (312) connected to the first shank section (311), the receiving cylinder (33) being connected to the first shank section (311), the first threaded section (312) supporting the first auxiliary nail (20).

9. Intramedullary nail assembly according to claim 3 or 8, characterized in that said second nail segment (32) comprises a second light bar segment (321), a third light bar segment (322) and a second threaded section (323) connected between said second light bar segment (321) and said third light bar segment (322), said second light bar segment (321) having an outer diameter smaller than the outer diameter of the outer wall of said third light bar segment (322), said abutment portion (34) being provided on the end face of said second light bar segment (321), the end of said third light bar segment (322) provided with an operating hole (3221) forming the second end of said second nail segment (32).

10. Intramedullary nail assembly according to claim 1, characterized in that a first end of the first auxiliary nail (20) is provided with an external thread (21), a second end of the first auxiliary nail (20) is provided with an operating slot (22), a first end of the first nail segment (31) supporting the external thread (21).

11. The intramedullary nail assembly of claim 1,

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

the intramedullary nail assembly further comprises a transverse nail (50) threaded through the fourth nail section (12).

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