High-stability bone extension bridging combined internal fixation device

Abstract

The utility model provides a high-stability bone extension bridging combined internal fixing device, and belongs to the technical field of bone extension. Comprising a first bone block and a second bone block, the plurality of fixing blocks are respectively arranged on the first bone block and the second bone block; the plurality of guide rods are arranged on the fixed block and are symmetrically arranged at the two ends of the fixed block; the fixing screw is arranged on the fixing block and is used for fixing the fixing block and a bone block; the fixing screw is provided with a screw body and a nut. By arranging the fixing screw, the fine threads at the bottom are beneficial to entering relatively loose sclerotin initially, the contact area and anchoring force with bone tissue can be increased along with the gradual thickening of the threads, and compared with a traditional single-thread screw, the fixing stability in an osteoporotic bone block can be effectively improved; and the loosening risk caused by insufficient friction force is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to bone lengthening technical field, especially in a kind of high stability bone lengthening bridging combination internal fixation device. BACKGROUND

[0002] Bone lengthening is distraction osteogenesis, that is, cut open bone, keep soft tissue and blood supply, then use special traction device to fix both ends, apply tension gradually to slowly pull bone segments, constantly stimulate body tissue, stimulate human tissue regeneration potential, form new bone between osteotomy gap, achieve the purpose of bone regeneration. External fixation frame or simple internal fixation device is usually used in lengthening operation.

[0003] In the fixing device, fixed screw is usually used to connect with bone block, and traditional fixed screw is usually single thread design. In osteoporotic bone tissue, due to low bone density, sparse trabecula and weak strength, the thread is difficult to be fully embedded, the contact area with bone is small, the friction is limited, and when subjected to external forces such as tension, pressure and shear force generated by limb activity for a long time, the limited friction cannot continuously counteract the external force, so the screw moves slightly in the bone hole, accumulates over time, and finally loosens and fails. Therefore, the present application provides a high-stability bone lengthening bridging combination internal fixation device to meet the needs. SUMMARY

[0004] The technical problem to be solved by the utility model is to provide a high-stability bone lengthening bridging combination internal fixation device to solve the problem that the existing fixed screw is usually single thread design, which cannot be used in osteoporotic bone tissue, and moves slightly after long-term use, causing loosening.

[0005] To solve the above technical problems, the utility model provides the following technical scheme.

[0006] A high-stability bone lengthening bridging combination internal fixation device, comprising: a first bone block and a second bone block; a plurality of fixed blocks arranged on the first bone block and the second bone block; a plurality of guide rods arranged on the fixed blocks and symmetrically arranged at both ends of the fixed blocks; a fixed screw arranged on the fixed block for fixing between the fixed block and the bone block; the fixed screw is provided with a screw body and a nut; the bottom of the screw body is provided with a fine thread, and the top of the screw body is provided with a coarse thread, and the thread between the fine thread and the coarse thread gradually increases along the coarse thread.

[0007] Further comprising: a plurality of guide sleeves sleeved on the guide rods.

[0008] The fixed block is made of high-strength, high-biocompatibility medical-grade material.

[0009] Further comprising: a connecting block arranged on the first bone block; and a moving block slidingly arranged on the guide rod and connected with the connecting block.

[0010] Further comprising: a moving rod arranged on the fixing block and penetrating through the fixing block at two ends thereof, and a thread arranged on the moving rod.

[0011] Further comprising: a connecting barrel sleeved on the moving rod and rotationally connected in the moving block, the connecting barrel being T-shaped, and a circulating channel and a ball arranged in the connecting barrel.

[0012] Further comprising: a driving rod arranged in the connecting barrel.

[0013] Further comprising: a plurality of lock nuts arranged at two ends of the moving rod respectively and used for adjusting a pre-tightening force.

[0014] Compared with the prior art, the utility model has at least the following beneficial effects.

[0015] In the above scheme, the fixed screw is arranged, the bottom fine thread is beneficial to initial entering of relatively loose bone, and with gradual thickening of the thread, the contact area and anchoring force with the bone tissue can be increased, compared with the traditional single thread screw, the fixed stability in the osteoporotic bone block can be effectively improved, and the loosening risk caused by insufficient friction can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a schematic view of a high-stability bone lengthening bridging combined internal fixation device.

[0017] Figure 2 It is a partial schematic view of a guide sleeve structure.

[0018] Figure 3 It is a schematic view of a fixed screw structure.

[0019] Figure 4 It is a schematic view of a driving rod structure.

[0020] [REFERENCE NUMERALS]

[0021] 1, first bone block; 2, fixing block; 3, guide rod; 4, second bone block; 5, fixed screw; 6, moving block; 7, moving rod; 8, guide sleeve; 9, driving rod; 10, connecting barrel; 11, connecting block; 51, nut; 52, shank; 71, lock nut.

[0022] As shown in the drawings, in order to clearly realize the structure of the embodiment of the utility model, specific structures and devices are marked in the drawings, but this is only for the need of illustration, and is not intended to limit the utility model in the specific structure, device and environment, according to the specific need, the ordinary skilled in the art can adjust or modify these devices and environment, and the adjustment or modification still includes in the range of the appended claims. DETAILED DESCRIPTION

[0023] The high-stability bone lengthening bridging combined internal fixation device provided by the utility model will be described in detail below in combination with the drawings and specific embodiments. It should be noted that the following embodiments are the best and preferred embodiments, and other alternative ways can also be used by those skilled in the art to implement some known technologies; moreover, the drawings are only used to more specifically describe the embodiments, and are not intended to specifically limit the utility model.

[0024] As Figure 1 Figure 4 The embodiment of the utility model provides a high-stability bone lengthening bridging combined internal fixation device, which comprises: a first bone block 1 and a second bone block 4; a plurality of fixing blocks 2 are arranged on the first bone block 1 and the second bone block 4 respectively; a plurality of guide rods 3 are arranged on the fixing blocks 2 and symmetrically arranged at both ends of the fixing blocks 2; fixing screws 5 are arranged on the fixing blocks 2 and used for fixing the fixing blocks 2 and the bone blocks; the fixing screws 5 are provided with screw bodies 52 and nuts 51; the bottom of the screw body 52 is provided with a fine thread, the top of the screw body 52 is provided with a coarse thread, and the thread between the fine thread and the coarse thread gradually increases along the coarse thread.

[0025] By arranging the fixing screws 5, when installing, the bottom fine thread can be easily screwed into bone tissue with different bone conditions, and the initial anchoring force can be established, the contact area and the occlusion degree of the bone tissue are continuously increased along with the gradually thickening thread, so that strong and stable anchoring effect can be provided in various bone conditions, whether it is relatively loose osteoporotic bone or normal bone tissue with hard texture, the loosening or displacement of the fixing blocks 2 relative to the bone blocks is effectively prevented, the relative position relationship between the bone blocks is maintained during the subsequent bone lengthening operation process, the components can work cooperatively based on the stable connection structure, various complex stresses such as tensile force, compression force and shear force can be borne, the safety and effectiveness of bone fixation during the postoperative recovery process of the bone lengthening operation are ensured, and the smooth progress of the bone lengthening operation is ensured.

[0026] ​Further comprising: a plurality of guide sleeves 8 sleeved on the guide rod 3. By arranging the guide sleeves 8, the moving block 6 needs to stably slide along the guide rod 3 when the bone lengthening operation is performed, the guide sleeves 8 can effectively constrain the movement track of the moving block 6, so that the moving block 6 moves strictly according to the predetermined direction, avoiding lateral deviation or shaking caused by external force interference or component self-processing error and the like, and the guide sleeves 8 can effectively reduce the friction coefficient between the moving components and the guide rod 3. In the long-term use process, especially in the frequent bone lengthening adjustment operation, the friction and wear between the components are inevitable, the guide sleeves 8 are made of materials with good self-lubricity and wear resistance, and a buffer and lubrication interface is formed between the guide rod 3 and the moving block 6 and the like related components, so that the friction resistance is reduced.

[0027] The fixed block 2 is made of medical-grade materials with high strength and high biocompatibility. Titanium and titanium alloy can be used, which has excellent biocompatibility in the human body environment. A stable titanium oxide film is naturally formed on the surface of the titanium and titanium alloy, which can prevent the release of metal ions and reduce the irritation to the surrounding tissues. Stainless steel can also be used, which contains a low carbon content to reduce the risk of intergranular corrosion in the human body. The surface of the stainless steel is relatively smooth and not easy to breed bacteria.

[0028] Further comprising: a connecting block 11 arranged on the first bone block 1; and a moving block 6 slidingly arranged on the guide rod 3, and the moving block 6 is connected with the connecting block 11. By arranging the connecting block 11 as a transition component between the moving block 6 and the first bone block 1, the effective transmission and dispersion of force are ensured. When the driving rod 9 drives the connecting cylinder 10 to move the moving block 6 along the guide rod 3, the connecting block 11 can accurately transmit the pulling force or pushing force generated by the movement to the first bone block 1, so that the first bone block 1 can be displaced relative to the second bone block 4 according to the predetermined direction and amplitude, thereby realizing precise bone lengthening operation.

[0029] Further comprising: a moving rod 7 arranged on the fixed block 2, both ends of the moving rod 7 penetrating through the fixed block 2, and threads are arranged on the moving rod 7. In cooperation with the ball and the circulating channel, the ball can roll along the tooth profile of the thread, so that the connecting cylinder 10 can accurately move axially along the threads on the moving rod 7.

[0030] Further comprising: a connecting cylinder 10 sleeved on the moving rod 7 and rotationally connected in the moving block 6, the connecting cylinder 10 is T-shaped, and the connecting cylinder 10 is provided with a circulating channel and a ball. By arranging the circulating channel, a given and standardized rolling path is provided for the ball, so that the ball can continuously and orderly circulate and roll, and the phenomenon of ball jamming or accumulation does not occur. The ball and the moving rod 7 are in rolling contact with the surface threads, and roll along the thread track.

[0031] Further comprising: a driving rod 9 arranged in the connecting cylinder 10. The rotation of the driving rod 9 is the starting link of converting the rotary motion into the linear motion. When the driving rod 9 rotates, the ball in the connecting cylinder 10 rolls on the thread of the moving rod 7, and finally drives the moving block 6 to move linearly along the guide rod 3, so as to pull apart the distance between the bone blocks, and realize the bone lengthening. The driving rod 9 can comprise an outer rod and an inner rod, and the inner rod is rotatably arranged in the outer rod and extends into the connecting cylinder 10. By rotating the inner rod, the connecting cylinder 10 is driven to move, so that the inner rod is not easily interfered by external factors during the rotation.

[0032] Further comprising: a plurality of lock nuts 71 arranged at two ends of the moving rod 7 respectively, used for adjusting the pre-tightening force. By arranging the lock nuts 71, the lock nuts 71 can be used for preliminarily fixing the position of the moving rod 7 during the installation of the device, and cooperate with the installation and adjustment of other components, so that the components are in the appropriate relative position before the formal use of the device, and have a certain pre-tightening force, so that the connecting parts are tightly fitted, and the components are prevented from being loose or displaced when not under stress. The above device has only one end of the driving rod 9 exposed outside the skin, and the other components are located in the skin.

[0033] The technical scheme provided by the utility model, through fixed screw 5 respectively with fixed block 2 is fixed on first bone block 1 and second bone block 4, when screwing in fixed screw 5, first utilize the fine thread portion of the bottom of nail body 52 and slowly rotate into the bone tissue, with the gradual thickening of the thread, continue to rotate until fixed block 2 and bone block are closely connected, when the bone gap between bone block is small, driving rod 9 rotates, through connecting cylinder 10 makes moving block 6 move along moving rod 7, the gap between bone block gradually increases, through the repeated adjustment of driving rod 9, when bone block is almost healed, readjust the gap between bone block, finally reach the purpose of bone lengthening.

[0034] The utility model covers any alternative, modification, equivalent method and scheme which is made on the essence and range of the utility model. In order to make the public have the thorough understanding of the utility model, the specific details are explained in the above preferred embodiment of the utility model, and the utility model can also be completely understood without the description of these details for the person skilled in the art. In addition, in order to avoid unnecessary confusion to the essence of the utility model, the well-known method, process, flow, element and circuit are not explained in detail.

[0035] The above is only the preferred embodiment of the utility model, and it should be pointed out that, for ordinary skilled person in the art, without departing from the principle of the utility model, a plurality of improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection range of the utility model.

Claims

1. A highly stable bone lengthening and bridging combined internal fixation device, characterized in that, include: First bone fragment (1) and second bone fragment (4); Several fixing blocks (2) are respectively disposed on the first bone block (1) and the second bone block (4); Several guide rods (3) are provided on the fixed block (2) and are symmetrically arranged at both ends of the fixed block (2); Fixing screws (5) are provided on the fixing block (2) for fixing the fixing block (2) to the bone block; The fixing screw (5) is provided with a screw body (52) and a nut (51); The bottom of the nail body (52) is provided with fine threads, and the top of the nail body (52) is provided with coarse threads. The thread between the fine threads and the coarse threads gradually increases along the coarse threads.

2. The high-stability bone lengthening bridging combined internal fixation device according to claim 1, characterized in that, Also includes: Several guide sleeves (8) are fitted onto the guide rod (3).

3. The high-stability bone lengthening bridging combined internal fixation device according to claim 1, characterized in that, The fixing block (2) is made of high-strength, highly biocompatible medical-grade material.

4. The high-stability bone lengthening bridging combined internal fixation device according to claim 1, characterized in that, Also includes: A connecting block (11) is disposed on the first bone block (1); The movable block (6) is slidably disposed on the guide rod (3), and the movable block (6) is connected to the connecting block (11).

5. The high-stability bone lengthening bridging combined internal fixation device according to claim 4, characterized in that, Also includes: A movable rod (7) is provided on the fixed block (2), and both ends of the movable rod (7) pass through the fixed block (2), and the movable rod (7) is provided with threads.

6. The high-stability bone lengthening bridging combined internal fixation device according to claim 5, characterized in that, Also includes: A connecting cylinder (10) is sleeved on the moving rod (7) and located inside the moving block (6) and rotatably connected. The connecting cylinder (10) is T-shaped and has a circulation channel and ball bearings inside.

7. The high-stability bone lengthening bridging combined internal fixation device according to claim 6, characterized in that, Also includes: The drive rod (9) is disposed inside the connecting cylinder (10).

8. The high-stability bone lengthening bridging combined internal fixation device according to claim 5, characterized in that, Also includes: Several anti-loosening nuts (71) are respectively set at both ends of the moving rod (7) for adjusting the preload.

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