An intramedullary nail fixation device for treating fractures of long tubular bones

Abstract

The application provides an intramedullary nail fixing device for treating long tubular bone fracture, and belongs to the technical field of medical instruments, which comprises a bendable hollow main nail and an elastic inner core nail; the distal end of the hollow main nail is fixed by rotating expansion of the inner core nail, the proximal end is inserted into the bone by the splittable insert piece, and the elastic inner core nail can provide a continuous pressure, which is beneficial to fracture healing. The intramedullary nail provided by the application is bendable and can be adapted to different bones and adaptive cavities; the intramedullary nail is fixed by internal fixation technology, does not need additional locking nail fixing, can reduce the operation difficulty, protects the blood vessels and muscles near the fractured bone, and reduces the pain of the patient.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to an intramedullary nail fixation device for treating fractures of long tubular bones. Background Technology

[0002] The clavicle is a slender, inverted "S"-shaped bone, comprising the sternal end articulating with the clavicular notch of the manubrium of the sternum medially, the acromial end articulating with the acromion of the scapula laterally, and the clavicular body in the middle. Clavicle fractures are generally caused by a fall where the shoulder or palm hits the ground, and the shear force transmitted to the clavicle exceeds the local bone strength. Fractures often occur at the junction of the middle and outer thirds of the clavicle. This junction has the smallest diameter and is only attached to the pectoralis major and infraclavicular muscles, making it the weakest point. Therefore, the middle third of the clavicle is prone to fracture, accounting for more than 75% of clavicle fractures. Depending on the location and severity of the fracture, various targeted treatment and recovery methods exist, such as Kirschner wire fixation, coracoclavicular screw fixation, clavicle plates, clavicle plate hooks, and intramedullary nail fixation, among other internal fixation techniques used to treat distal clavicle fractures. In intramedullary nails and locking screws are used; the main nail is implanted into the intramedullary space of the clavicle, and then locking screws are used to vertically cross and lock the two ends of the main nail. Because the scapular region is densely populated with the suprascapular artery, dorsal scapular artery, and circumflex scapular artery, and locking nails require numerous incisions, they are highly susceptible to damage to arteries and muscle tissue during practical application. Therefore, locking nail fixation is not suitable for intramedullary nailing in clavicle fractures. Furthermore, due to the "S" shape of the clavicle, conventional straight intramedullary nails are unsuitable for clavicle fractures. While existing flexible intramedullary nails can meet the requirements of the "S"-shaped clavicle curvature, the aforementioned problems arise during locking fixation, resulting in high risk, poor applicability, and limited clinical use. Summary of the Invention

[0003] The purpose of this invention is to provide an intramedullary nail fixation device for treating fractures of long tubular bones.

[0004] To solve the above-mentioned technical problems, the objective of this invention is achieved as follows:

[0005] An intramedullary nail fixation device for treating fractures of long tubular bones, characterized in that it comprises: a hollow main nail, an inner core rod, a insert, and a tail cap;

[0006] The hollow master nail is hollow and flexible inside, and its distal end can expand to achieve distal fixation of the intramedullary nail.

[0007] The inner core rod is an elastic rod, inserted inside the hollow main nail; by rotating the inner core rod, the distal end of the hollow main nail can be expanded;

[0008] The insert is movably connected to the inner core rod and can expand outward to insert into the bone to achieve proximal fixation of the intramedullary nail;

[0009] The tail cap is connected with the proximal end section of the inner core rod, and can push the insert sheet to expand outward.

[0010] On the basis of the above scheme and as a preferred scheme of the above scheme, the hollow main nail comprises a proximal end section, a middle flexible shaft section and a distal end section; the proximal end section is provided with a plurality of through grooves uniformly distributed along the circumference to cooperate with the insert sheet; the middle flexible shaft section comprises a helical groove; the helical groove is helically distributed in the middle of the hollow main nail and is formed by penetrating the hollow main nail; the distal end section is provided with a plurality of circumferentially distributed grooves, and the grooves extend from the distal end of the hollow main nail to the proximal end.

[0011] On the basis of the above scheme and as a preferred scheme of the above scheme, a support block is movably arranged in the distal end section, the support block comprises a tapered portion and a connecting section; the connecting section is in a hollow cylindrical structure, the tail end is fixedly connected with the tapered portion, and the head end is used for being screwed into the inner core rod; the inner wall of the hollow cylindrical structure is provided with a thread.

[0012] On the basis of the above scheme and as a preferred scheme of the above scheme, the inner core rod comprises a rod main body; the rod main body gradually increases in diameter from the distal end to the proximal end, and the proximal end is provided with a proximal end thread to cooperate with the tail cap, and the distal end is provided with a distal end thread to cooperate with the support block; the proximal end of the rod main body is provided with a rotating groove to facilitate rotating the inner core rod.

[0013] On the basis of the above scheme and as a preferred scheme of the above scheme, the number of the insert sheets is at least two, and the insert sheets are uniformly arranged along the circumference.

[0014] On the basis of the above scheme and as a preferred scheme of the above scheme, the insert sheet is connected to the inner core rod through a shaft sleeve; the shaft sleeve is slidingly sleeved on the inner core rod; the insert sheet comprises a tip and a tail end, the tail end is hinged to the shaft sleeve, and a sliding groove is formed in the side surface; a protrusion is arranged in the sliding groove in a matched mode, and the protrusion is fixedly arranged on the hollow main nail; the sliding groove satisfies that when the shaft sleeve moves to the distal end of the intramedullary nail, the tip is raised under the limitation of the protrusion.

[0015] On the basis of the above scheme and as a preferred scheme of the above scheme, the tail cap comprises a fixedly connected light rod portion and a driving portion; a threaded through hole is formed in the center of the light rod portion to cooperate with the inner core rod, and the tail end of the light rod portion can abut against the shaft sleeve and push the shaft sleeve to move, and the head end is fixedly connected with the driving portion; a through hole is formed in the center of the driving portion and communicates with the threaded through hole, and an edge is arranged on the outer side surface to facilitate tool rotation.

[0016] The beneficial effects of the present application are:

[0017] The present application aims at the three arteries and muscle tissues near the scapula position which can be hurt by the conventional intramedullary nail locking, adopts the expansion structure at the distal end and the insert piece structure at the proximal end, and can realize the intramedullary nail fixation inside the bone, which is safer.

[0018] The present application adopts the soft body design, can better adapt to different patients, can be used for the fracture position with complex structure such as clavicle and pelvic bone, and is simple to implant, can effectively reduce the operation time and operation difficulty, and reduces the operation cost.

[0019] The elastic inner core rod can not only realize the rotary expansion internal fixation in the curved intramedullary nail, but also can realize the continuous pressure by the elastic design of the inner core rod, which is helpful for stimulating the fracture position and accelerating the fracture healing. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is the structural schematic diagram of the present application.

[0021] Figure 2 It is the schematic diagram of the hidden hollow main nail of the present application.

[0022] Figure 3 It is the structural schematic diagram of the hollow main nail of the present application.

[0023] Figure 4 It is the structural schematic diagram of the inner core rod of the present application.

[0024] Figure 5 It is the structural schematic diagram of the supporting block of the present application.

[0025] Figure 6 It is the structural schematic diagram of the tail cap of the present application.

[0026] Figure 7 It is the structural schematic diagram of the insert piece and shaft sleeve of the present application.

[0027] In the figure: 1, hollow main nail; 11, proximal end section; 12, middle flexible shaft section; 121, spiral groove; 13, distal end section; 14, through groove; 15, slotted; 16, supporting block; 161, taper part; 162, connecting section; 2, inner core rod; 21, rod main body; 22, proximal end thread; 23, distal end thread; 24, rotation groove; 3, insert piece; 31, sliding groove; 32, protruding block; 4, tail cap; 41, smooth rod part; 42, driving part; 43, threaded through hole; 5, shaft sleeve; DETAILED DESCRIPTION

[0028] The present application will be further described below in combination with the drawings and specific embodiments.

[0029] As shown in Figure 1 and Figure 2 , an intramedullary nail fixing device for treating long tubular bone fracture comprises a hollow main nail 1, an inner core rod 2, an insert piece 3 and a tail cap 4.

[0030] like Figure 3 As shown, the hollow main nail 1 has a cylindrical hollow structure and is flexible, including an integrally formed proximal section 11, a central flexible shaft section 12, and a distal section 13.

[0031] The proximal section 11 has a through groove 14. The through groove 14 is square, and there are several of them, which are evenly distributed around the circumference of the hollow main nail 1. The through groove 14 extends from the outer surface of the hollow main nail 1 to the inner surface.

[0032] The central flexible shaft segment 12 includes a helical groove 121, which is spirally distributed in the middle of the hollow main nail 1, extending from the outer surface of the hollow main nail 1 to the inner surface, and has a linear, wavy structure. The helical groove 121 allows the middle of the hollow main nail 1 to bend, which is suitable for internal fixation of non-linear bone fractures.

[0033] The distal segment 13 has several slots 15 evenly distributed around the circumference of the hollow main nail 1. The slots 15 extend from the distal end of the hollow main nail 1 to the proximal end. The distal segment 13 is divided into several segments by the slots 15, which can be expanded to achieve internal fixation of the distal end of the hollow main nail 1.

[0034] A support block 16 is movably provided inside the distal segment 13, and the support block 16 includes a cone 161. By pulling the support block 16 toward the center of the hollow main nail 1, the cone 161 opens the distal segment 13 to achieve internal fixation.

[0035] Preferably, such as Figure 5 As shown, the support block 16 includes an integral conical portion 161 and a connecting section 162. The connecting section 162 has a hollow cylindrical structure with threads on its hollow inner wall. The tail end is fixedly connected to the conical portion 161, and the head end is used to screw into the inner core rod 2. The diameter of the conical portion 161 gradually increases from the tail end of the connecting section 162.

[0036] like Figure 2 and Figure 4 As shown, the inner core rod 2 is an elastic rod that is inserted into the hollow main nail. Its two ends are threaded to the support block 16 and the tail cap 4, respectively. By rotating the inner core rod 2, the support block 16 is moved to open the distal segment 13, thereby achieving distal fixation of the intramedullary nail.

[0037] Specifically, the inner core rod 2 includes a rod body 21. The proximal end of the rod body 21 has a proximal thread 22 to engage with the tail cap 4, and the distal end has a distal thread 23 to engage with the support block 16. The diameter of the rod body 21 gradually increases from the distal end to the proximal end. The proximal thread 22 and the connecting section 162 of the support block 16 achieve a threaded connection, and the distal thread 23 and the thread on the tail cap 4 achieve a threaded connection. A groove 24 is formed at the proximal end of the rod body 21 to allow a tool to be inserted and rotated. The groove 24 is formed by an inward indentation at the end of the rod body 21.

[0038] The insert is movably connected to the inner core rod 2 and can expand outward to insert into the bone to achieve proximal fixation of the intramedullary nail. Preferably, there are at least two inserts 3, which are movably connected to the inner core rod 2, evenly distributed along the circumference of the inner core rod 2, and disposed in the through groove 14, so as to expand outward to insert into the bone to fix the proximal end of the intramedullary nail.

[0039] Specifically, such as Figure 7 As shown, the insert 3 is connected to the inner core rod 2 via a bushing 5. The bushing 5 has a circular ring structure and slides onto the inner core rod 2. The insert 3 includes a tip and a tail end, with the tail end hinged to the outer surface of the bushing 5 and having grooves 31 on both sides. A movable protrusion 32 is fitted into the groove 31, and the protrusion 32 is fixedly mounted on the side wall of the groove 15 and is cylindrical. As the diameter of the inner core rod 2 gradually increases, the movement of the bushing 5 is restricted.

[0040] The groove 31 allows the tip of the sleeve 5 to be inserted into the bone under the constraint of the protrusion 32 as it moves towards the distal end of the intramedullary nail. Specifically, the tail end of the insert 3 is hinged to the sleeve 5 by a pin. The hollow main nail 1 has a through hole to allow the pin and protrusion 32 to be inserted during assembly.

[0041] like Figure 6 As shown, the tail cap 4 includes a smooth rod portion 41 and a driving portion 42. The smooth rod portion 41 is cylindrical, with a threaded through hole 43 in the center to accommodate the inner core rod 2. Simultaneously, the tail end can abut against the bushing 5 and the insert 5, pushing the bushing 5 and the insert 3 to move. The head end is fixedly connected to the driving portion 42. The driving portion 42 has a through hole in the center communicating with the threaded through hole, and its outer surface is provided with edges to facilitate tool rotation. Preferably, the outer surface of the driving portion 42 is hexagonal, allowing the tool to rotate the driving portion 42 and drive the tail cap 4 to rotate. When the tail cap 4 is threadedly connected to the near end of the inner core rod 2, due to the presence of the threaded through hole 43 and the through hole, the tool can pass through the tail cap 4 and engage with the groove 24 at the end of the inner core rod 2.

[0042] Assembly process: First, insert the support block 16 from the distal end 13 port, then insert the inner core rod 2 from the proximal end 11 port to thread it onto the support block 16. Next, assemble the tail cap 4 and thread it onto the proximal end of the inner core rod 2. Before inserting the hollow main nail 1 into the inner core rod 2, first put the bushing 5 onto the inner core rod 2. Then, insert the insert 3 into the slot 14, and then insert the pin through the through hole on the hollow main nail 1 to hinge the insert 3 to the bushing 5. Then, insert the protrusion 32 through another through hole to engage with the sliding groove 31 of the insert 3 and fix it to the hollow main nail 1.

[0043] Working process: First, assemble the hollow main nail 1, inner core rod 2, insert 3, bushing 5, and support block 16. Then, insert them into the prepared intramedullary cavity. After implantation, use a tool to rotate the inner core rod 2 to pull the support block 16, thus opening the distal segment 13 of the hollow main nail 1 to fix the distal segment of the intramedullary nail. When rotating the inner core rod 2, the insert 3 will pre-tilt up as a limiting structure to restrict the movement of the inner core rod 2 distally, thereby pulling back the support block 16. Then, use a tool to drive the tail cap 4 to rotate and move it to the distal end of the intramedullary nail. Its end will push the bushing 5 and insert 3 to move to the distal end of the intramedullary nail as well, so that the insert 3 is opened in the slot 15 and inserted into the bone to achieve internal fixation of the proximal end of the intramedullary nail. After the insert 3 is fixed, continue to rotate the tail cap 4. The insert will not continue to expand. At this time, the tail cap 4 will stretch the elastic inner core rod 2, so that the inner core rod 2 has a certain elasticity. Under the action of the elastic force of the inner core rod 2, it will give the bone a continuous pressure, so that the two fractured bones will squeeze each other, which is conducive to improving the healing effect.

[0044] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. An intramedullary nail fixation device for treating fractures of long tubular bones, characterized in that, include: Hollow main nail (1), inner core rod (2), insert (3), tail cap (4); The hollow master nail (1) is hollow and flexible inside, and its distal end can expand to achieve distal fixation of the intramedullary nail. The inner core rod (2) is an elastic rod, which is inserted into the hollow main nail (1); by rotating the inner core rod (2), the distal end of the hollow main nail (1) can be expanded; The insert (3) is movably connected to the inner core rod (2) and can expand outward to insert into the bone to achieve proximal fixation of the intramedullary nail; The tail cap (4) is connected to the proximal section of the inner core rod (2), which can push the insert (3) to expand outward; The insert (3) is connected to the inner core rod (2) via a bushing (5); the bushing (5) is slidably sleeved on the inner core rod (2); the insert (3) includes a tip and a tail, the tail is hinged to the bushing (5), and a groove (31) is provided on the side; a protrusion (32) is provided in the groove (31), and the protrusion (32) is fixedly provided on the hollow main nail (1); the groove (31) satisfies that when the bushing (5) moves toward the distal end of the intramedullary nail, the tip is tilted upward under the restriction of the protrusion (32); The tail cap (4) includes a smooth rod part (41) and a drive part (42) that are fixedly connected; the smooth rod part (41) has a threaded through hole (43) in the center to cooperate with the inner core rod (2), and the tail end of the smooth rod part (41) can abut against the bushing (5) and push the bushing (5) to move, and the head end is fixedly connected to the drive part (42); the drive part (42) has a through hole in the center that communicates with the threaded through hole (43), and the outer side is provided with edges to allow the tool to rotate.

2. The intramedullary nail fixation device for treating fractures of long tubular bones according to claim 1, characterized in that, The hollow main pin (1) includes a proximal section (11), a middle flexible shaft section (12), and a distal section (13). The proximal section (11) has several through slots (14) evenly distributed along the circumference to cooperate with the insert (3). The middle flexible shaft section (12) includes a spiral groove (121). The spiral groove (121) is spirally distributed in the middle of the hollow main pin (1) and is formed by penetrating the hollow main pin (1). The distal section (13) has several slots (15) evenly distributed along the circumference, and the slots (15) extend from the distal end of the hollow main pin (1) to the proximal end.

3. The intramedullary nail fixation device for treating fractures of long tubular bones according to claim 2, characterized in that, The distal section (13) is movably provided with a support block (16), which includes a cone (161) and a connecting section (162); the connecting section (162) has a hollow cylindrical structure, with its tail end fixedly connected to the cone (161) and its head end used to screw into the inner core rod (2); the inner wall of the hollow cylindrical structure is threaded.

4. The intramedullary nail fixation device for treating fractures of long tubular bones according to claim 3, characterized in that, The inner core rod (2) includes a rod body (21); the rod body (21) has a gradually increasing rod diameter from the distal end to the proximal end, and the proximal end is provided with a proximal thread (22) to cooperate with the tail cap (4), and the distal end is provided with a distal thread (23) to cooperate with the support block (16); a swivel groove (24) is opened at the proximal end of the rod body (21) to allow the inner core rod (2) to rotate.

5. The intramedullary nail fixation device for treating fractures of long tubular bones according to claim 1, characterized in that, The number of inserts (3) is at least two, and they are evenly arranged along the circumference.

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