阅读说明：本技术 一种骨水泥髓内钉固定系统 (Bone cement intramedullary nail fixing system ) 是由 张嘉 许小波 张强 郑晓明 钱政 于 2021-08-26 设计创作，主要内容包括：本专利涉及一种骨水泥髓内钉固定系统,包括髓内钉主钉、骨水泥螺钉、扩张器械、拉力钉、骨水泥注射器,髓内钉主钉的近端设有第一螺钉孔和第二螺钉孔；骨水泥螺钉安装于第一螺钉孔；骨水泥螺钉沿轴向贯穿设有中心孔,侧壁上设有骨水泥扩散孔,骨水泥扩散孔与中心孔连通；扩张器械通过中心孔在骨松质内部形成一个空腔；骨水泥注射器通过中心孔和骨水泥扩散孔向空腔内注射骨水泥；拉力钉安装于第二螺钉孔,拉力钉的前端位于空腔内的骨水泥中。本发明通过骨水泥螺钉和拉力钉配合使髓内钉固定及植入后防旋,拉力钉的外螺纹与骨水泥螺钉的齿槽啮合,在旋动拉力钉后,能够使骨水泥螺钉带着已注入骨水泥的骨折块回移,对骨折部位起到加压作用。(The patent relates to a bone cement intramedullary nail fixing system, which comprises an intramedullary nail main nail, a bone cement screw, a dilation instrument, a tension nail and a bone cement injector, wherein a first screw hole and a second screw hole are arranged at the near end of the intramedullary nail main nail; the bone cement screw is arranged in the first screw hole; the bone cement screw is provided with a central hole in an axial penetrating manner, the side wall is provided with a bone cement diffusion hole, and the bone cement diffusion hole is communicated with the central hole; the expansion appliance forms a cavity in the cancellous bone through the central hole; the bone cement injector injects the bone cement into the cavity through the central hole and the bone cement diffusion hole; the pull nail is arranged in the second screw hole, and the front end of the pull nail is positioned in the bone cement in the cavity. The invention prevents rotation after the intramedullary nail is fixed and implanted by matching the bone cement screw and the tension nail, the external thread of the tension nail is meshed with the tooth socket of the bone cement screw, and after the tension nail is rotated, the bone cement screw can carry the fracture block which is injected with bone cement to move back, thereby exerting a pressurizing effect on the fracture part.)

1. A bone cement intramedullary nail fixation system, comprising:

an intramedullary nail main nail (1), the intramedullary nail main nail (1) comprising a proximal end (11) and a distal end (12), the proximal end (11) having a cross-sectional dimension greater than the distal end (12); a first screw hole (13) and a second screw hole (14) are formed in the lower portion of the near end (11), and the first screw hole (13) is located above the second screw hole (14);

a bone cement screw (2), the bone cement screw (2) being mounted to the first screw hole (13); the bone cement screw (2) is provided with a central hole (23) in an axial penetrating manner, a side wall of the bone cement screw (2) is provided with a bone cement diffusion hole (24), and the bone cement diffusion hole (24) is communicated with the central hole (23);

a dilating instrument (3), said dilating instrument (3) forming a cavity inside cancellous bone through said central hole (23);

a bone cement injector (5), said bone cement injector (5) injecting bone cement (6) into said cavity through said central bore (23) and said bone cement diffusion bore (24);

the tension nail (4) is installed on the second screw hole (14), and the front end of the tension nail (4) is located in the bone cement (6) in the cavity.

2. The bone cement intramedullary nail fixation system according to claim 1, characterized in that the bone cement screw (2) comprises a first threaded section (21) and a polished rod section (22), the bone cement diffusion hole (24) being provided on the first threaded section (21), the polished rod section (22) being provided with a cutting slot (26);

the pull nail (4) comprises a head part (41) and a second thread section (42), and the thread of the second thread section (42) is matched with the cutting groove (26);

the threaded section (42) is rotated under the restriction of the cutting groove (26) so that the tension nail (4) and the bone cement screw (2) are relatively moved.

3. The bone cement intramedullary nail fixation system according to claim 2, characterized in that the aperture of the second screw hole (14) is provided with an aperture step (16), and the head (41) is provided with a stop which can be snapped onto the aperture step (16).

4. The bone cement intramedullary nail fixation system according to claim 2, wherein the threads of the second thread section (42) are trapezoidal threads.

5. The bone cement intramedullary nail fixation system according to claim 2, characterized in that the head (41) is provided with a counter sink (43), the counter sink (43) being provided with a thread structure (44), the counter sink (43) being adapted to cooperate with an instrument for implanting the tension nail (4).

6. The bone cement intramedullary nail fixation system according to claim 2, characterized in that the tail end of the light rod segment (22) is provided with two deep grooves (25), in which deep grooves (25) deep groove threads are provided, for cooperation with instruments for implanting bone cement screws (2).

7. The bone cement intramedullary nail fixing system according to claim 2, wherein the outer peripheral wall of the light rod section (22) is provided with a circular arc groove (28) along the axial direction, the circular arc groove (28) is arranged on two sides of the cutting groove (26) along the axial direction of the light rod section (22), the diameter of the circular arc groove (28) is larger than or equal to the outer diameter of the second thread section (42), and the top end of the groove side wall of the cutting groove (26) exceeds the groove bottom of the circular arc groove (28).

8. The cement intramedullary nail fixation system according to any one of claims 1 to 7, characterized in that a centerline of the first screw hole (13) is parallel to a centerline of the second screw hole (14);

after the pull nail (4) is installed on the second screw hole (14), the angle between the second thread section (42) and the far end (12) is 120-140 degrees.

9. The bone cement intramedullary nail fixation system according to any one of claims 1 to 8, characterized in that the expansion instrument (3) comprises a front end provided with a distraction balloon (31) and a rear end for controlling the contraction or distraction of the distraction balloon (31).

10. The bone cement intramedullary nail fixation system according to claim 9, wherein the bone cement injector (5) comprises a push handle (52) and a delivery tube (51), the delivery tube (51) is detachably connected with the push handle (52), the delivery tube (51) is used for penetrating into the central hole (23) of the bone cement screw (2), and the push handle (52) is pushed to make the bone cement (6) enter the cavity through the delivery tube (51) and through the bone cement diffusion hole (24).

Technical Field

This patent belongs to medical instrument technical field, particularly relates to a bone cement intramedullary nail fixing system.

Background

Femoral trochanteric fracture is one of the most common fracture types in clinic, is frequently generated in the elderly, is caused by direct external force, and is commonly suffered from osteoporosis in the elderly. The early-stage operation treatment is mainly adopted clinically, so that better clinical curative effect can be obtained, and the advantages of early load bearing time, good fracture reduction, few complications and the like are achieved. Because the femur has unique anatomical and biomechanical characteristics and needs a long time to heal after being fractured and treated, the selection of a proper repair mode plays a very important role in healing the fracture and improving the prognosis of the patient.

The treatment method adopted in the past is suitable for the internal fixation of the fracture of a patient by using an anatomical steel plate, but the method has certain limitations on blood supply of the fracture, serious comminuted fracture and the like, and has the problems of poor healing and the like frequently generated after operation. Therefore, intramedullary nail internal fixation is used to replace anatomical steel plate internal fixation in recent years. The intramedullary nail has the advantages that the intramedullary nail can reduce the force arm and prevent adverse reactions such as internal and external rotation angulation, fixation failure and the like, and in addition, the intramedullary nail has better elasticity, can only cause a little intraosseous movement when being pressed, can be immediately restored after being deformed, has a structure conforming to the biological fixation principle, and has various effects of rotation resistance, compression resistance and the like. However, in patients with osteoporosis, the presence of osteoporosis leads to a decrease in bone mass and also to changes in bone structure and composition, including thinning of cortical bone, sparse fracture of trabecular bone, and the like. Therefore, the intramedullary nail may be implanted with tension nail loosening, cutting, displacement and other adverse events, and finally the internal fixation fails.

In recent years, many physicians have begun to choose to use cement intramedullary nails for internal fixation in patients with osteoporosis. Research shows that the intramedullary nail internal fixation device reinforced by the bone cement can form a three-combined interface of the bone, the bone cement and the surface of the screw in the femoral neck, can effectively reduce the strong stress of the tension nail directly on the osteoporotic bone, enhance the stability of the tension nail, and effectively prevent the occurrence rate of complications such as cutting-out and cutting-through of the screw from the femoral head. The use method is that the hollow bone cement tension nail with the side hole is firstly driven into the drilled femoral neck, and then the bone cement is injected into the bone cement tension nail through the hollow conduit. Because the small holes are all positioned at the front part of the tension nail, the injected bone cement can be ensured to be uniformly distributed around the head part of the tension nail of the bone cement, and the bone cement is prevented from leaking into the fractured end. However, the existing bone cement tension nail has poor stability and is easy to withdraw, and the method of directly injecting bone cement has obvious defects, which are mainly embodied in that:

1. because the cavity is not formed in the bone, the bone cement needs to be injected under a large pressure, the injection amount is usually small, and the effect of strengthening the fixation cannot be achieved;

2. forced injection also increases the risk of leakage of cement, especially at the proximal position of the femur, which, if it enters the joint cavity of the hip joint, would have an effect on the movement of the lower extremities and would require surgical cleanup.

Disclosure of Invention

In view of the above analysis, the present invention aims to provide an air sterilization device to solve the problems of poor stability and easy nail removal of the existing bone cement intramedullary nail fixation system using bone cement tension nails.

The purpose of the invention is realized as follows:

a bone cement intramedullary nail fixation system comprising:

a main intramedullary nail comprising a proximal end and a distal end, the proximal end having a cross-sectional dimension greater than the distal end; a first screw hole and a second screw hole are formed in the lower portion of the near end, and the first screw hole is located above the second screw hole;

a bone cement screw mounted to the first screw hole; the bone cement screw is provided with a central hole in an axial penetrating manner, a bone cement diffusion hole is formed in the side wall of the bone cement screw, and the bone cement diffusion hole is communicated with the central hole;

a dilation instrument, said dilation instrument forming a cavity within cancellous bone through said central bore;

a bone cement injector that injects bone cement into the cavity through the central bore and the bone cement diffusion bore;

the tension nail is installed in the second screw hole, and the front end of the tension nail is located in the bone cement in the cavity.

In a preferred embodiment of the present invention, the bone cement screw comprises a first threaded section and a polished rod section, the bone cement diffusion hole is disposed on the first threaded section, and the polished rod section is provided with a cutting groove; the pull nail comprises a head part and a second thread section, and the thread of the second thread section is matched with the cutting groove; the threaded section rotates under the limitation of the cutting groove, so that the tension nail and the bone cement screw move relatively.

In a preferred embodiment of the present invention, the hole of the second screw hole is provided with a hole step, and the head is provided with a position-limiting part which can be engaged with the hole step.

In a preferred embodiment of the present invention, the thread of the second thread segment is a trapezoidal thread.

In a preferred embodiment of the invention, the head is provided with a counter sink, the counter sink is provided with a thread structure, and the counter sink is used for matching with an instrument for implanting the tension nail.

In a preferred embodiment of the present invention, the tail end of the polished rod segment is provided with two deep grooves, the deep grooves are provided with deep groove threads, and the deep grooves are used for matching with an instrument for implanting a bone cement screw.

In a preferred embodiment of the present invention, the outer peripheral wall of the polished rod section is provided with arc grooves along the axial direction, the arc grooves are arranged on both sides of the cutting groove along the axial direction of the polished rod section, the diameter of the arc groove is greater than or equal to the outer diameter of the second thread section, and the top end of the groove side wall of the cutting groove exceeds the groove bottom of the arc groove.

In a preferred embodiment of the present invention, the cross section of the proximal end is trapezoidal, the cross section of the distal end is circular, and the proximal end and the distal end are connected in a transition manner.

In a preferred embodiment of the present invention, a bifurcated groove is provided at an insertion end of the distal end, and a longitudinal section of the bifurcated groove is a U-shaped structure; the number of the bifurcating grooves is 1, or the number of the bifurcating grooves is 2, and the bifurcating grooves are symmetrically arranged on two sides of the center line of the far end.

In a preferred embodiment of the present invention, a center line of the first screw hole is parallel to a center line of the second screw hole; after the pull nail is installed in the second screw hole, the angle between the second thread section and the far end is 120-140 degrees.

In a preferred embodiment of the present invention, the dilating instrument comprises a front end and a rear end, the front end is provided with a dilating balloon, and the rear end is used for controlling the dilating balloon to contract or dilate.

In a preferred embodiment of the present invention, the bone cement injector comprises a pushing handle and a delivery tube, wherein the delivery tube is detachably connected to the pushing handle, and is configured to penetrate into a central hole of the bone cement screw, and push the pushing handle to allow bone cement to pass through the delivery tube and enter the cavity through the bone cement diffusion hole.

According to a preferred embodiment of the invention, an internal threaded hole is formed in the end portion of the proximal end, the internal threaded hole is communicated with the first screw hole, a tail cap is mounted in the internal thread of the internal threaded hole, and the tail cap can be abutted against a bone cement screw and a tension screw after being mounted in the internal threaded hole.

In a preferred embodiment of the invention, the tail cap comprises a cap head part and a cap rod part, and the cap head part and the cap rod part are of an integrated structure.

In a preferred embodiment of the present invention, the cap head is provided with an inner hexagonal counter sink structure and an outer hexagonal counter sink structure.

In a preferred embodiment of the present invention, the cap head further has a convex section and a transition section, the outer hexagonal structure is connected to the transition section through the convex section, the diameter of the outer peripheral wall of the convex section is larger than any one of the diameters of the outer hexagonal structure and the outer peripheral wall of the transition section, and the diameter of the outer peripheral wall of the convex section is equal to the diameter of the inner threaded hole of the proximal end.

Compared with the prior art, the invention can realize at least one of the following beneficial effects:

a) the invention provides a bone cement intramedullary nail fixing system, wherein a first screw hole and a second screw hole are arranged at the near end of a main intramedullary nail, a cutting groove is formed in a polished rod section of a bone cement screw, the bone cement screw is firstly installed in the first screw hole, and when a tension screw is installed in the second screw hole, the thread of the second thread section of the tension screw can be meshed with the cutting groove of the polished rod section of the bone cement screw. The intramedullary nail is fixed by matching the bone cement screw and the tension nail, so that the intramedullary nail can be prevented from rotating after being implanted, and the tension nail can be implanted into a proper position by the hole step arranged at the hole of the second screw hole.

b) According to the bone cement intramedullary nail fixing system provided by the invention, the bone cement screw and the expansion instrument are combined for use, so that a sufficient space is provided for bone cement, the pressure for injecting the bone cement into cancellous bone is reduced, and the risk of repairing femoral trochanter fracture of osteoporosis patients is reduced.

c) According to the bone cement intramedullary nail fixing system provided by the invention, after the tension nail is arranged in the second screw hole of the intramedullary main nail, the angle between the second thread section of the tension nail and the far end is 120-140 degrees, the angle is matched with the hip joint cervical shaft angle of Chinese population, the fracture repair can be better provided, and the clinical curative effect of the intramedullary nail fixing system is ensured.

d) According to the bone cement intramedullary nail fixing system provided by the invention, the tail cap is installed on the end part thread of the proximal end of the main nail of the intramedullary nail, when the main nail of the intramedullary nail, the bone cement screw, the tension nail and the locking nail are all implanted, the tail cap is implanted through the internal thread hole, the tail cap props against the bone cement screw and the tension nail after being implanted, and meanwhile, the axial stability of the bone cement screw and the tension nail is ensured and the risk of withdrawing the bone cement tension nail and the tension nail is reduced by matching the design of the spongy bone thread of the bone cement screw.

Drawings

In order to more clearly illustrate the embodiments of the present specification or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the embodiments of the present specification, and other drawings can be obtained by those skilled in the art according to the drawings.

FIG. 1 is a first schematic view illustrating a use process of the bone cement intramedullary nail fixing system of the present invention;

FIG. 2 is a schematic view illustrating a second operation of the bone cement intramedullary nail fixing system according to the present invention;

FIG. 3 is a schematic structural view of the bone cement intramedullary nail fixation system of the present invention;

FIG. 4 is a schematic structural view of the intramedullary nail main nail of the present invention;

FIG. 5 is a schematic structural view of the bone cement tension nail of the present invention;

FIG. 6 is a schematic structural view of a tension nail according to the present invention;

FIG. 7 is a schematic structural view of the dilation instrument of the present invention;

FIG. 8 is a schematic structural view of a bone cement injector according to the present invention;

FIG. 9 is a schematic view of the structure of the bone cement screw and the main nail of the intramedullary nail of the present invention;

FIG. 10 is a schematic structural view of the tail cap of the present invention;

fig. 11 is a schematic structural view of the tail cap of the present invention.

Reference numerals:

1-intramedullary nail main nail; 11-a proximal end; 12-a distal end; 13-a first screw hole; 14-a second screw hole; 15-a split slot; 16-orifice step; 2-bone cement screws; 21-a first thread segment; 22-a polished rod section; 23-a central hole; 24-bone cement diffusion holes; 25-deep groove; 26-cutting a groove; 27-circular arc-shaped notch; 28-arc groove; 3-a dilation instrument; 31-opening the balloon; 32-back end; 4-tension nails; 41-a head; 42-a second thread section; 43-sink tank; 44-a thread structure; 5-bone cement injector; 51-a delivery pipe; 52-push handle; 6-bone cement; 7-tail cap; 71-a cap head; 711-external hexagonal structure; 712-a bump; 713-a transition section; 714-inner hexagonal sink structure; 72-cap stem portion; 73-thread.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. 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 application.

For the purpose of facilitating understanding of the embodiments of the present application, the following description will be made in terms of specific embodiments with reference to the accompanying drawings, which are not intended to limit the embodiments of the present application.

One embodiment of the present invention, as shown in fig. 1-2, discloses a bone cement intramedullary nail fixation system, comprising:

the intramedullary nail comprises an intramedullary nail main nail 1, wherein the intramedullary nail main nail 1 comprises a near end 11 and a far end 12, and the cross section size of the near end 11 is larger than that of the far end 12; a first screw hole 13 and a second screw hole 14 are arranged at the lower part of the proximal end 11, and the first screw hole 13 is positioned above the second screw hole 14;

a bone cement screw 2, the bone cement screw 2 being mounted to the first screw hole 13; the bone cement screw 2 is provided with a central hole 23 along the axial direction in a penetrating way, the side wall of the thread part of the bone cement screw 2 is provided with a bone cement diffusion hole 24, and the bone cement diffusion hole 24 is communicated with the central hole 23;

the expansion instrument 3 can be expanded after passing through the central hole 23, and a cavity is finally formed in the bone floss;

the bone cement injector 5 injects the bone cement 6 into the cavity through the central hole 23 and the bone cement diffusion hole 24;

the tension nail 4 is installed on the second screw hole 14, the front end of the tension nail 4 is positioned in the bone cement 6 in the cavity and is matched with the bone cement screw 2 for use, so that the anti-rotation and pressurization effects after the intramedullary nail is implanted are guaranteed.

In a preferred embodiment of the present embodiment, the bone cement screw 2 comprises a first thread section 21 and a polished rod section 22, a central hole 23 is axially formed through the first thread section 21 and the polished rod section 22, the central hole 23 can pass through the expansion device 3 or the bone cement injector 5, a bone cement diffusion hole 24 is formed in the first thread section 21, and the bone cement diffusion hole 24 is communicated with the central hole 23 for diffusing the bone cement 6.

In a preferred embodiment of this embodiment, the threads of the first thread segments 21 are cancellous bone threads, which provides greater resistance to pullout for patients with osteoporosis. At least one bone cement diffusion hole 24 is arranged between the adjacent screw teeth, so that the bone cement 6 can be injected into the femoral head of the osteoporosis patient in an all-around manner. Optionally, the bone cement diffusion holes 24 are round holes with a diameter of 1-3mm, so that the bone cement 6 can be injected uniformly.

In a preferred embodiment of this embodiment, the rod segment 22 of the bone cement screw 2 is provided with a cutting groove 26; the pull nail 4 comprises a head part 41 and a second threaded section 42, the thread of the second threaded section 42 is matched with the cutting groove 26, the thread pitch of the second threaded section 42 is the same as the distance between the cutting grooves 26 of the polished rod section 22, and the groove width of the cutting groove 26 is larger than or equal to the thread width of the pull nail 4; the threaded section 42 rotates within the confines of the slot 26 to allow the lag screw 4 and the bone cement screw 2 to move relative to each other. After the bone cement 6 is injected into the body through the bone cement screw 2, the tension nail 4 can enter the body of the patient through the second screw hole 14 on the near end 11 of the main intramedullary nail 1 in a rotating mode, at the moment, the tension nail 4 can be continuously implanted into a proper position due to the fact that the bone cement screw 2 is provided with the cutting groove 26, the intramedullary nail is prevented from rotating, and the femoral trochanter fracture of the patient with osteoporosis can be treated more stably.

Nail withdrawing is one of the frequently occurring problems for osteoporosis patients, and once nail withdrawing occurs, the internal fixation loses the effect. A preferred embodiment of this embodiment, the tip of intramedullary nail main nail near-end 11 sets up the internal thread hole, can cooperate the use with tail cap 7, internal thread hole and first screwed hole 13 intercommunication, when intramedullary nail main nail 1, bone cement screw 2, lag screw 4, the lock nail is whole to be implanted the back, tail cap 7 accessible internal thread hole is implanted, bear bone cement screw 2 and lag screw 4 after tail cap 7 is implanted, cooperate the design of the spongy bone screw thread of the first screw thread section 21 of bone cement screw 2 simultaneously, guarantee bone cement screw 2 and the axial stability of lag screw 4, reduce the risk that bone cement lag screw and lag screw retreat the nail. In addition, the anti-rotation effect of the tension nail on the bone cement tension nail completely ensures the stability of the bone cement tension nail.

In a preferred embodiment of the present embodiment, the tail cap 7 includes a cap head portion 71 and a cap rod portion 72, and the cap head portion 71 and the cap rod portion 72 of the tail cap 7 are of an integrated structure, so that the structure is simple and the processing is convenient; the cap rod part 72 is provided with an external thread structure 73, and the external thread of the cap rod part 72 is matched with the internal thread of the proximal end 11 of the intramedullary nail, so that the tail cap 7 is screwed into the proximal end of the intramedullary nail through the thread until the tail cap 7 abuts against the bone cement screw 2 and the tension nail 4.

In a preferred embodiment of this embodiment, the head portion 71 is provided with an internal hexagonal counter sink structure 714 to facilitate implantation of the tail cap 7. In addition, the cap head part 71 is further provided with an outer hexagonal structure 711, the hexagonal sunken groove structure 714 and the outer hexagonal structure 711 are coaxially arranged, after the tail cap 7 is implanted, the outer hexagonal structure 711 is exposed at the outer side of the proximal end 11 of the intramedullary nail, and when the implant needs to be taken out and the inner hexagonal structure cannot be used due to bone ingrowth, the implant can be taken out through the outer hexagonal structure.

In a preferred embodiment of this embodiment, the cap head 71 is further provided with a convex section 712 and a transition section 713, the hexagonal outer structure 711 is connected with the transition section 713 through the convex section 712, the diameter of the outer peripheral wall of the convex section 712 is larger than any one of the diameters of the outer peripheral walls of the hexagonal outer structure 711 and the transition section 713, it can also be understood that the cap head 71 is connected with the cap rod 72 through the transition section 713, the convex section 712 is connected with a first end of the transition section 713, the diameter of the convex section 712 is larger than the diameter of the hexagonal outer structure 711, and a second end of the transition section 713 is connected with the cap rod 72; the size of the convex section 712 is consistent with the size of the internal thread hole at the proximal end of the main intramedullary nail, and after the tail cap 7 is implanted into the internal thread hole arranged at the proximal end 11 of the main intramedullary nail, the peripheral wall of the convex section 712 can be contacted with the wall of the internal thread hole at the proximal end of the main intramedullary nail, so that the situation that after the tail cap 7 is implanted, bones cannot grow into the main intramedullary nail is ensured, and conditions are provided for subsequent nail taking.

In a preferred embodiment of this embodiment, the outer peripheral wall of the polish rod segment 22 is provided with circular arc grooves 28 along the axial direction, the circular arc grooves 28 are provided on both sides of the cutting groove 26 along the axial direction of the polish rod segment 22, the diameter of the circular arc groove 28 is greater than or equal to the outer diameter of the second thread section 42, and the top end of the groove side wall of the cutting groove 26 exceeds the groove bottom of the circular arc groove 28, as shown in fig. 3, the lower end of the outer peripheral wall of the bone cement screw 2 is provided with a circular arc groove 28, the diameter of the circular arc groove 28 is slightly greater than the outer diameter of the tension nail 4, the top end of the side wall of the cutting groove 26 is provided with a circular arc notch 27, the circular arc notch 27 is greater than or equal to the thread bottom diameter of the tension nail 4, optionally, the circular arc notch 27 is coincident with the center line of the circular arc groove 28 and coaxial with the second screw hole 14 of the proximal end 11 of the intramedullary nail 1, when the tension nail 4 is screwed through the second screw hole 14, the external thread of the tension nail 4 can be engaged with the cutting groove 26, the internal thread can engage with the circular arc shaped indentation 27. This structure and the cooperation of lag screw 4 and design, the polished rod section 22 that can make bone cement screw 2 is hugging closely circular arc groove 28 and is removing, and, the tank bottom of circular arc groove 28 is surpassed on the top of the groove lateral wall of grooving 26, circular arc breach 27 diameter more than or equal to 4 screw thread footpaths of lag screw, guarantee lag screw 4 at the precession in-process, the screw thread and the grooving 26 meshing of second screw thread section 42, and remove along the circular arc groove 28 of bone cement screw 2, guarantee the accuracy of 4 mounted positions of lag screw, guarantee simultaneously that turning of lag screw 4 soon more unobstructed, and the installation effectiveness is improved, guarantee treatment.

In a preferred embodiment of the present embodiment, the first screw hole 13 is larger in size for passing through the bone cement screw 2, and the second screw hole 14 is smaller in size for passing through the tension nail 4, so that two screw installation errors can be prevented by differently sizing the first screw hole 13 and the second screw hole 14.

In a preferred embodiment of this embodiment, the opening of the second screw hole 14 is provided with an opening step 16, and the head 41 can be snapped onto the opening step 16. Specifically, the head 41 is provided with a stopper which can be engaged with the orifice step 16; alternatively, the hole of the second screw hole 14 is provided with the hole step 16, and the size of the head 41 of the tension nail 4 is larger than that of the second threaded section 42, and it can also be understood that the annular end surface at the joint of the head 41 and the second threaded section 42 forms a limiting part. After the tension nail 4 is implanted into the body through the second screw hole 14, the hole step 16 is contacted with the head 41 of the tension nail 4, the annular end surface or the limiting part can limit the advance of the tension nail 4, the position of the tension nail 4 is ensured, and when the tension nail 4 is continuously rotated, the bone cement screw 2 can bring the fracture block which is injected with the bone cement to move back, so that the pressure effect on the fracture part is realized.

In a preferred embodiment of this embodiment, the threads of the second thread segments 42 are trapezoidal threads. Because the tension nail 4 needs to be matched with the bone cement screw 2 for implantation, the design of the trapezoidal thread can ensure the root strength, the excellent wear resistance and the more excellent transmission effect.

In a preferred embodiment of this embodiment, the thread front end of the second thread segment 42 has a chip groove, which facilitates the removal of bone chips during implantation and reduces the self-tapping force of the product.

In a preferred embodiment of the present embodiment, the head 41 of the tension nail 4 is provided with a sunken groove 43, the sunken groove 43 is used for cooperating with an instrument for implanting the tension nail 4 to facilitate the implantation of the tension nail 4, the sunken groove 43 is provided with a thread structure 44, and the existence of the thread structure 44 can ensure the stability of the tension nail 4 during the implantation process.

In a preferred embodiment of this embodiment, the tail end of the rod segment 22 is provided with two deep grooves 25, and deep groove threads are provided in the deep grooves 25, and the deep grooves are used for matching with the instrument for implanting the bone cement screw 2. In the implantation process, the deep groove thread can be matched with a corresponding instrument to ensure the stability of the bone cement screw 2 in the implantation process, and the two deep grooves 25 can be matched with the screw driver to be used, so that the bone cement screw 2 can be conveniently implanted.

In a preferred embodiment of this embodiment, the proximal end 11 has a trapezoidal cross-section, the distal end 12 has a circular cross-section, and the proximal end 11 is connected to the distal end 12 in a transition manner. By arranging the proximal end 11 as a trapezoid structure, when a patient performs hip joint flexion and extension, the proximal end of the femur is at the maximum pressure level, and the proximal end 11 of the trapezoid structure can ensure the stability of the intramedullary nail at the maximum pressure level; by providing distal end 12 with a rounded configuration, implantation of the intramedullary nail in the medullary cavity is facilitated.

In a preferred embodiment of this embodiment, the proximal end 11 of the trapezoid structure has a first side wall and a second side wall opposite to each other, a groove is formed in a lower portion of the first side wall, a bottom of the groove is a flat surface, which is called a bottom plane of the groove, the bottom plane of the groove is disposed obliquely upward, the first screw hole 13 and the second screw hole 14 are disposed in the bottom plane of the groove, the first screw hole 13 and the second screw hole 14 are arranged in an "8" shape on the bottom plane of the groove, and the bottom plane of the groove forms an angle of 120 ° -140 ° -degree with the distal end 12

In a preferred embodiment of this embodiment, the center line of the first screw hole 13 is parallel to the center line of the second screw hole 14; after the bone cement screw 2 is installed in the first screw hole 13 and the tension screw 4 is installed in the second screw hole 14, the center line of the bone cement screw 2 is parallel to the center line of the tension screw 4.

In a preferred embodiment of the present embodiment, after the tension nail 4 is installed in the second screw hole 14, the angle between the second thread section 42 and the distal end 12 is 120 ° to 140 °, and the angle is set to match the hip stem angle of chinese population, so as to ensure the clinical efficacy of the intramedullary nail fixing system.

In a preferred embodiment of this embodiment, the insertion end of the distal end 12 is provided with a forked groove 15, and the longitudinal section of the forked groove 15 is of a U-shaped structure; the number of the bifurcating grooves 15 is 1, or the number of the bifurcating grooves 15 is 2, and the bifurcating grooves are symmetrically arranged on two sides of the center line of the distal end 12. The distal end 12 of the intramedullary nail main nail 1 is provided with the bifurcation slot 15, so that the distal end 12 has certain elasticity, and when the intramedullary nail main nail is implanted, the stress of the distal end 12 of the intramedullary nail main nail can be reduced due to the existence of the bifurcation slot 15, and the stress fracture caused by the stimulation of the bone wall is avoided.

In a preferred embodiment of this embodiment, the dilating device 3 comprises a front end and a rear end, the front end is provided with the dilating balloon 31, the rear end is used for controlling the dilating balloon 31 to contract or dilate, the dilating balloon 31 can extend into cancellous bone through the central hole 23 in the contracted state, and the rear end controls the dilating balloon 31 to dilate in cancellous bone to form a cavity. The expansion appliance 3 is used in the following manner: the front end of the expansion balloon is inserted into cancellous bone along the central hole 23 of the bone cement screw 2 in a contracted state, the front end of the expansion balloon can extend out of the first thread section 21 of the bone cement screw 2, the rear end 32 is controlled to expand the expansion balloon 31 at the front end, cancellous bone can expand a cavity, and after the cavity is formed, the rear end is controlled to contract the expansion balloon 31 at the front end, and the expansion balloon 31 in the contracted state is removed from the central hole 23.

In a preferred embodiment of the present embodiment, the bone cement injector 5 includes a push handle 52 and a delivery tube 51, and the delivery tube 51 is detachably connected to the push handle 52. After a cavity is formed in the cancellous bone, the delivery pipe 51 is inserted into the central hole 23 of the bone cement screw 2, the delivery pipe 51 of the bone cement injector 5 extends along the central hole 23 and is inserted into the cancellous bone to the same depth as the bone cement diffusion hole 24, and the push handle 52 is pushed to enable the bone cement 6 to enter the cavity expanded by the expansion appliance 3 through the delivery pipe 51 via the bone cement diffusion hole 24 of the first thread section 21.

The implementation of the bone cement intramedullary nail fixing system of the embodiment for treating the osteoporosis patient with femoral trochanter fracture specifically comprises the following steps:

the method comprises the following steps: placing the patient in a proper position, incising the cortex at the upper end of the femur, finding a nail feeding point of the intramedullary nail, opening the nail feeding position and drilling an intramedullary nail placing channel; the intramedullary nail main nail 1 is inserted into the femoral bone marrow cavity by using an instrument;

step two: matching the deep groove 25 of the bone cement screw 2 by using a corresponding instrument, and stably implanting the bone cement screw 2 to the first screw hole 13 of the proximal end 11 of the intramedullary nail main nail 1 to a proper position by using the lower end thread of the bone cement screw 2;

step three: the expansion instrument 3 is inserted into the central hole 23 of the bone cement screw 2 until the screw thread section is penetrated, the spongy bone is expanded, and the expansion instrument 3 is pulled out after being contracted.

Step four: the cement screw 2 is continued to be screwed into the fixation position. The bone cement injector is inserted into the bone cement screw hole to a proper position, and the bone cement 6 is injected.

Step five: matching the sunken grooves 43 of the tension nails 4 by using corresponding instruments, and stably implanting the tension nails 4 to the second screw holes 14 of the proximal ends 11 of the intramedullary nail main nails 1 by using the threads at the lower ends of the tension nails 4; the pulling force nail 4 is at the implantation in-process, and the pulling force nail 4 can be passed through the rotatory patient's of implanting of second screw hole 14 entering on the intramedullary nail main nail 1 internal, because the bone cement screw 2 is equipped with grooving 26 this moment, can make the pulling force nail 4 continue to implant to suitable position, plays the anti-rotation effect to the intramedullary nail, and the more stable treatment osteoporosis patient's femoral tuberosity fracture. The head 41 of the tension nail 4 is screwed into the hole step 16 on the intramedullary nail main nail 1 to make contact. The tension nail 4 is rotated continuously, so that the bone cement screw 2 moves backwards to a proper pressurizing position, the bone cement screw 2 carries the bone fracture block which is injected with bone cement to move backwards, and the pressurizing effect is achieved on the fracture part.

Step six: after the tension nail 4 is installed, the screw at the far end 12 is locked, and the operation is completed after suturing.

Compared with the prior art, the bone cement intramedullary nail fixing system provided by the embodiment has the following beneficial effects:

1. the bone cement screw is used in combination with the expansion instrument, so that sufficient space is provided for bone cement, the pressure for pushing the bone cement into cancellous bone is reduced, and the risk of repairing femoral tuberosity fracture of an osteoporosis patient is reduced.

2. The near end of the intramedullary nail main nail is provided with a first screw hole and a second screw hole, the polished rod section of the bone cement screw is provided with a cutting groove, the bone cement screw is firstly installed in the first screw hole, and when the tension nail is installed in the second screw hole, the thread of the second thread section of the tension nail can be meshed with the cutting groove of the polished rod section of the bone cement screw. This structural arrangement can guarantee on the one hand that the intramedullary nail is prevented rotating after implanting, and on the other hand, the drill way step that the drill way of second screw hole set up can guarantee that the pulling force nail implants suitable position to at bone cement screw with implant the back, along with the continuation of pulling force nail revolve soon, bone cement screw takes the fracture piece that has injected into bone cement to move back, plays the pressurization effect to the fracture position.

3. The bone cement screw has a central hole with a larger diameter so as to ensure that the expansion appliance 3 can smoothly enter the central hole, the threaded end of the bone cement screw is provided with bone cement diffusion holes, and the number and the aperture of the bone cement diffusion holes are more suitable for pushing the bone cement.

4. The bone cement screw and the tension screw are respectively of two deep grooves and a sunk groove structure, and the lower ends of the two deep grooves and the sunk groove structures are both provided with thread structures and matched with corresponding instruments for use, so that the stability of the implant during implantation is ensured.

5. The near end of the intramedullary nail main nail is of a trapezoidal structure, so that the stability of the implanted product is ensured.

6. After the tension nail is arranged in the second screw hole of the main nail of the intramedullary nail, the angle between the second thread section of the tension nail and the far end is 120-140 degrees, the angle is set to be matched with the hip joint cervical shaft angle of Chinese people, the fracture can be better repaired, and the clinical curative effect of the intramedullary nail fixing system is ensured.

The above-mentioned embodiments, objects, technical solutions and advantages of the present application are described in further detail, it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present application, and are not intended to limit the scope of the present application, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present application should be included in the scope of the present application.