Bone fixation system and tensioner for "8" cerclage of distal tibiofibular separation

Abstract

The present invention relates to the field of medical technology, and discloses a bone fixation system and a tensioner for "8" cerclage for tibia-fibular separation. The bone fixation system comprises a bone plate, a cerclage cable and two hard pipes forked and inserted into the tibia; the bone plate is fixed on the fibula; the cerclage cable covers the bone plate on the fibula, and the two ends of the cerclage cable respectively pass through the hollow inner cavity of the hard pipe so that the cerclage cable crosses into an "8" shape. The present invention crosses the cerclage cable in the hard pipe in the tibia so that the cerclage cable forms an "8" shape, and uses a tensioner to achieve tensioning of the cerclage cable, which is easy to operate and is also conducive to the control of the tension of the cerclage cable by medical personnel, ensuring that the cerclage cable is not easy to loosen and slip, and the reduction and fixation of the tibia-fibular separation is reliable; when the fracture stability allows, the patient can walk on the ground with weight at an early stage, avoiding the problem that the screw is easily broken when walking with weight before the screw is removed when the position screw is fixed, and avoiding secondary surgery.

Description

Technical Field

[0001] The invention relates to the field of medical technology, in particular to a bone fixing system and a tensioner thereof for "8"-shaped cerclage for tibiofibular separation. Background Art

[0002] As a weight-bearing joint, the ankle joint bears a great load in walking, standing, running and jumping. The tibiofibular syndesmosis is of great significance in maintaining the integrity and stability of the ankle. According to the Lauge-Hansen classification, ankle fractures are classified as supination-external rotation and pronation-abduction fractures with varying degrees of tibiofibular syndesmosis damage, which accounts for more than 60% of ankle fractures. After the tibiofibular syndesmosis is separated, the stability of the ankle joint is destroyed, the ankle hole is widened, and the talus is displaced outward, then the pressure per unit area is significantly increased. When the talus is displaced outward by 1mm, the tibiotalar contact surface decreases by 42%. If not treated in time, pain, swelling and traumatic inflammatory changes will occur in the late stage, leading to the patient's loss of labor, seriously affecting life, work, and even society and family.

[0003] Because ankle injuries are often accompanied by tibiofibular separation, the fixation of such injuries mainly uses tibiofibular screws and bolts. This type of fixation device installs bolts by driving screws or drilling holes transversely into the tibia and fibula. However, its disadvantage is that the reduction is unreliable, loosening and slipping of the thread are prone to occur, and dislocation may still occur after surgery. Summary of the invention

[0004] Based on the above problems, the present invention provides a bone fixation system and a tensioner for the "8"-shaped cerclage for tibiofibular separation, wherein the tibiofibular syndesmosis is reduced by a cerclage cable, and the cerclage cable is crossed in a hard tube in the tibia to form an "8" shape. The cerclage cable is tightened by the tensioner, which is convenient to operate and is also beneficial for medical personnel to control the tension of the cerclage cable, thereby ensuring that the cerclage cable is not prone to loosening and slippage, and the reduction and fixation of the tibiofibular separation are reliable. If the stability of the fracture permits, the patient can walk on the ground with weight at an early stage, thereby avoiding the problem of screw breakage caused by weight-bearing walking before the screw is removed when position screw fixation is used, thereby avoiding secondary surgery.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] The bone fixation system for the "8" cerclage of the distal tibia and fibula separation comprises a bone plate, a cerclage cable for fixing the distal tibia and fibula, and two hard pipes arranged in the tibia, wherein the two hard pipes are cross-pierced in the tibia, and the diameter of the cerclage cable is smaller than the inner diameter of the hard pipes; a plurality of nail holes are arranged on the bone plate, and the bone plate is fixed on the fibula by means of locking screws; the cerclage cable is sleeved over the bone plate on the fibula, and the two ends of the cerclage cable are respectively passed through the hollow inner cavity of the hard pipe so that the cerclage cable crosses into an "8" shape, and then is locked with a lock buckle on the side of the tibia facing away from the fibula.

[0007] Furthermore, the hard pipe is a channel screw, which includes a nail cap and a nail rod. The outer wall of the distal end of the nail rod is provided with a thread, and the nail cap is provided with a cutting edge for rotating the channel screw; the channel screw is provided with a through hole penetrating the nail cap and the nail rod along the central axis.

[0008] Furthermore, the through hole diameter of the channel screw is 1.5 mm.

[0009] Furthermore, a plurality of limiting grooves are laterally arranged at the end of the bone plate fixed to the distal end of the fibula, and the limiting grooves are located on the surface of the bone plate away from the fibula.

[0010] In order to solve the above technical problems, the present invention also provides a tensioner for "8"-shaped cerclage of distal tibiofibular separation, comprising a first hinged rod and an adjusting screw, characterized in that: a threaded hole matching the adjusting screw is arranged at the middle position of the first hinged rod, the threaded hole is perpendicular to the length direction of the first hinged rod, and the adjusting screw is passed through the threaded hole; the two ends of the first hinged rod are symmetrically hinged with tensioning plates, and the two tensioning plates and the adjusting screw are located in the same plane; a second hinged rod is arranged at one end of the adjusting screw, a through hole with a diameter larger than the diameter of the adjusting screw is arranged at the middle position of the second hinged rod, two positioning blocks are fixed on the adjusting screw, and the second hinged rod is located between the two positioning blocks; two connecting rods are symmetrically hinged at the end of the second hinged rod, and the two connecting rods are respectively hinged to the two tensioning plates; a wire clamping mechanism for fixing the cerclage cable is arranged on the opposite sides of the two tensioning plates.

[0011] Furthermore, a wire groove is provided between the end of the tensioning head and the wire clamping mechanism.

[0012] Furthermore, the wire clamping mechanism includes a bolt fixed on the tensioning plate, a threading hole for the cerclage steel cable to pass through is arranged in the middle of the bolt, and a knob clamp is threadedly connected to the bolt.

[0013] Furthermore, a rotating handle is provided at the end of the adjusting screw rod away from the second hinge rod.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention uses a cerclage cable to reduce the tibiofibular syndesmosis, and the cerclage cable crosses in the hard tube in the tibia to form an "8" shape, and the reduction and fixation of the tibiofibular separation is reliable; if the fracture stability allows, the patient can walk with weight on the ground at an early stage, avoiding the problem of screw breakage caused by weight-bearing walking before the screw is removed when position screw fixation is used, and avoiding secondary surgery. When the cerclage cable is tightened, the two ends of the cerclage cable that fix the tibia and fibula are cross-fixed by using the wire clamping mechanism on the tensioning plate, and the opening and closing degree of the tensioning plate is controlled by rotating the adjusting screw to achieve the tightening of the cerclage cable. The operation is convenient, and it is also beneficial for medical personnel to control the tension of the cerclage cable, which satisfies the fixation of the tibiofibular syndesmosis while ensuring that the cerclage cable is not prone to loosening and slippage. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a top view of the structure of the bone fixation system for the "8" cerclage for the tibiofibular separation in Example 1;

[0016] Figure 2 It is a side structural diagram of the bone fixation system for the "8" cerclage for the tibiofibular separation in Example 1;

[0017] Figure 3 It is a cross-sectional structural diagram of the channel screw along the central axis in Example 1;

[0018] Figure 4 is a schematic structural diagram of the bone fracture plate in Example 1;

[0019] Figure 5 It is a schematic structural diagram of a tensioner used for tibiofibular separation cerclage in Example 2;

[0020] Figure 6 for Figure 5 Side view of the center tension sheet;

[0021] Figure 7 It is a structural schematic diagram of the wire clamping mechanism in Example 2;

[0022] Figure 8 It is a structural schematic diagram of the tensioner in Example 2 when tightening the cerclage cable;

[0023] Among them: 1. Bone plate; 2. Cerclage cable; 3. Hard pipe; 4. Locking screw; 5. Lock buckle; 6. Nail cap; 7. Nail rod; 8. Limiting groove; 9. Tibia; 10. Fibula; 11. First hinge rod; 12. Adjusting screw; 13. Tensioning plate; 14. Second hinge rod; 15. Positioning block; 16. Connecting rod; 17. Wire guide groove; 18. Bolt; 19. Threading hole; 20. Knob clamp; 21. Rotating handle. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0025] Embodiment 1:

[0026] See also Figure 1 and Figure 2 The bone fixation system for the "8" cerclage of the tibia and fibula separation comprises a bone plate 1, a cerclage cable 2 for fixing the tibia and fibula, and two hard pipes 3 arranged in the tibia 9, wherein the two hard pipes 3 are cross-pierced in the tibia 9, and the diameter of the cerclage cable 2 is smaller than the inner diameter of the hard pipes 3; a plurality of nail holes are arranged on the bone plate 1, and the bone plate 1 is fixed on the fibula 10 by means of locking screws 4; the cerclage cable 2 is sleeved over the bone plate 1 on the fibula 10, and the two ends of the cerclage cable 2 are respectively passed through the hollow inner cavity of the hard pipe 3 so that the cerclage cable 2 crosses into an "8" shape, and then is locked with a lock buckle 5 on the side of the tibia 9 facing away from the fibula 10.

[0027] In this embodiment, after the patient has tibiofibular separation, the bone plate 1 is fixed to the fibula 10 by means of the locking screws 4, and then holes are cross-drilled on both sides of the fibular notch of the tibia 9 (the distal end of the tibia 9 is enlarged, the cross section is square, and there is a concave articular surface on the outside called the fibular notch), that is, the Volkman tubercle and the Chaput tubercle, the two drilled holes are close to each other but not connected to each other, and then the hard pipe 3 is installed in the hole; the tibiofibular syndesmosis is then reduced, and then the middle position of the cerclage cable 2 is fitted with the bone plate 1, and the two ends of the cerclage cable 2 are respectively inserted from the two hard pipe 3 ends of the Volkman tubercle and the Chaput tubercle, and the cerclage cable 2 cross-passes through the two hard pipes 3, and the two ends of the cerclage cable 2 passing through the hard pipes 3 are tightened by a tensioner on the side of the tibia 9 facing away from the fibula 10, and are locked and fixed with a lock buckle 5 to form an "8" shape, and finally the excess cerclage cable is cut off with a cable pliers. The present invention performs tibiofibular syndesmosis reduction by means of a cerclage cable 2, and the cerclage cable 2 crosses in a hard tube 3 in a tibia 9 so that the cerclage cable 2 forms an "8" shape, and reduction and fixation are reliable, achieving good functional recovery; and if fracture stability permits, the patient can walk with weight on the ground at an early stage; the problem that the screws are easily broken when walking with weight before the screws are removed in the existing tibiofibular syndesmosis surgery using position screws for fixation is avoided, thereby avoiding secondary surgery.

[0028] In this embodiment, the lock buckle 5 adopts a steel sleeve that can simultaneously insert two sections of the cerclage steel cable 2. Before the two ends of the cerclage steel cable 2 are cross-fixed, the two ends of the cerclage steel cable 2 are first cross-passed through the steel sleeve, and then tightened with a tensioner and the tension is controlled. After tightening, the steel sleeve is compressed with a caliper, so that the steel sleeve bites the cerclage steel cable 2, thereby achieving the locking and fixation of the cerclage steel cable 2.

[0029] See also Figure 1 and Figure 3 The hard pipe 3 used in this embodiment is a channel screw, which includes a cap 6 and a rod 7. The outer wall of the distal end of the rod 7 is provided with a thread, and the cap 6 is provided with a knife edge for rotating the channel screw; the channel screw is provided with a through hole penetrating the cap 6 and the rod 7 along the central axis. The thread provided on the distal outer wall of the channel screw can generate a force between the tibia 9 and the channel screw, and will not slide out of the tibia 9. Before inserting the channel screw, first use a drill bit to drill a hole slightly smaller than the outer diameter of the channel screw at the corresponding position on the tibia 9, and then use a screwdriver to screw the channel screw into the tibia 9; the through hole diameter of the channel screw used in this embodiment is 1.5 mm, and the corresponding diameter of the cerclage cable 2 is 1.2 mm.

[0030] See also Figure 3 and Figure 4 The end of the bone plate 1 fixed to the distal end of the fibula 10 is transversely provided with a plurality of limiting grooves 8, and the limiting grooves 8 are located on the surface of the bone plate 1 away from the fibula 10. The bone plate 1 corresponding to the distal end of the fibula 10 is designed with a transverse limiting groove 8 on the outside of the fibula 10 away from the fibula 10, which can prevent the cerclage cable 2 from sliding excessively, and can also allow a certain physiological micro-motion between the cerclage cable 2 and the bone plate 1, avoiding the use of rigid screws or bolts to fix and is not conducive to the repair of the physiological healing characteristics of the ligament itself.

[0031] Embodiment 2:

[0032] See also Figure 5 and Figure 8 , a tensioner for tibiofibular separation "8" cerclage, comprising a first hinged rod 11 and an adjusting screw 12, a threaded hole matching the adjusting screw 12 is arranged at the middle position of the first hinged rod 11, the threaded hole is perpendicular to the length direction of the first hinged rod 11, and the adjusting screw 12 is passed through the threaded hole; two ends of the first hinged rod 11 are symmetrically hinged with tensioning pieces 13, and the two tensioning pieces 13 and the adjusting screw 12 are located in the same plane; one end of the adjusting screw 12 is provided with a second hinged rod 14, a through hole with a diameter larger than that of the adjusting screw 12 is arranged at the middle position of the second hinged rod 14, two positioning blocks 15 are fixed on the adjusting screw 12, and the second hinged rod 14 is located between the two positioning blocks 15; two connecting rods 16 are symmetrically hinged at the end of the second hinged rod 14, and the two connecting rods 16 are respectively hinged on the two tensioning pieces 13; the opposite sides of the two tensioning pieces 13 are provided with a wire clamping mechanism that can fix the cerclage cable 2.

[0033] In this embodiment, after the tibia and fibula are reset, the cerclage cable 2 is passed around the tibia 9 and the fibula 10, and then the two ends of the cerclage cable 2 are cross-fixed on the two clamping mechanisms; because the tensioning plate 13 is hinged on the first hinge rod 11, the second hinge rod 14 is driven to extend and retract by rotating the adjusting screw 12, so that the connecting rod 16 hinged between the second hinge rod 14 and the tensioning plate 13 drives the tensioning plate 13 to open and close, thereby tightening and loosening the cerclage cable 2. Medical personnel can judge the tension of the cerclage cable 2 by the change in the spacing between the first hinge rod 11 and the second hinge rod 14, or can also judge the tension of the cerclage cable 2 by the degree of force of rotating the adjusting screw 12, so that it can meet the stable cerclage of the tibia and fibula without over-tension. After tightening, the cerclage cable 2 overlapping each other between the two tensioning plates 13 is locked into a loop with the lock buckle 5. The present invention utilizes the wire clamping mechanism on the tensioning plate 13 to cross-fix the two ends of the cerclage cable 2 for fixing the tibia 9 and the fibula 10, and then controls the opening and closing degree of the tensioning plate 13 by rotating the adjusting screw 12 to achieve the tightening of the cerclage cable 2. The operation is convenient and it is also beneficial for medical personnel to control the tension of the cerclage cable 2. While satisfying the fixation of the tibiofibular joint, it ensures that the cerclage cable 2 is not prone to loosening and slipping.

[0034] See also Figure 5 , Figure 6 and Figure 8 A wire groove 17 is provided between the end of the tensioning head and the wire clamping mechanism, and the ligature steel cable 2 can be clamped in the wire groove 17 during the tensioning process, thereby avoiding the ligature steel cable 2 from slipping on the outside of the tensioning plate 13 during the tensioning process of the ligature steel cable 2, and further ensuring the tension of the ligature steel cable 2.

[0035] See also Figure 5 and Figure 6 The wire clamping mechanism of this embodiment includes a bolt 18 fixed on the tensioning sheet 13, a threading hole 19 for the cerclage steel cable 2 to pass through is provided in the middle of the bolt 18, and a knob clamp 20 is threadedly connected to the bolt 18. In actual operation, the two ends of the cerclage steel cable 2 are firstly crossed through the threading holes 19 of the two bolts 18, the size of the cerclage steel cable 2 is adjusted, and then the cerclage steel cable 2 is fixed in the threading holes 19 of the bolt 18 by rotating the knob clamp 20, and the cerclage steel cable 2 is not easy to slide during the tensioning process.

[0036] See also Figure 5 A rotating handle 21 is provided at the end of the adjusting screw 12 away from the second hinge rod 14. The rotation of the adjusting screw 12 is controlled by rotating the handle 21. The rotation of the adjusting screw 12 is more labor-saving and convenient for medical staff to operate.

[0037] The above is an embodiment of the present invention. The above embodiments and the specific parameters in the embodiments are only for the purpose of clearly describing the invention verification process, and are not intended to limit the patent protection scope of the present invention. The patent protection scope of the present invention is still subject to its claims. Any equivalent structural changes made by using the contents of the description and drawings of the present invention should be included in the protection scope of the present invention.

Claims

1. A bone fixation system for "8" cerclage of distal tibiofibular separation, characterized by: The invention comprises a bone plate (1), a cerclage cable (2) for fixing the lower tibia and fibula, and two hard pipes (3) arranged in the tibia (9), wherein the two hard pipes (3) are cross-arranged in the tibia (9), and the diameter of the cerclage cable (2) is smaller than the inner diameter of the hard pipes (3); the bone plate (1) is provided with a plurality of nail holes, and the bone plate (1) is fixed to the fibula (10) by means of locking screws (4); the cerclage cable (2) is sleeved over the bone plate (1) on the fibula (10), and the two ends of the cerclage cable (2) are respectively passed through the hollow inner cavity of the hard pipe (3) so that the cerclage cable (2) crosses to form a cerclage cable (2). After the "8", the tibia (9) side facing away from the fibula (10) is locked with a lock buckle (5); the hard pipe (3) is a channel screw, and the channel screw comprises a screw cap (6) and a screw rod (7), the outer wall of the distal end of the screw rod (7) is provided with a thread, and the screw cap (6) is provided with a knife edge for rotating the channel screw; the channel screw is provided with a through hole penetrating the screw cap (6) and the screw rod (7) along the central axis; the end of the bone plate (1) fixed to the distal end of the fibula (10) is transversely provided with a plurality of limit grooves (8), and the limit grooves (8) are located on the surface of the bone plate (1) away from the fibula (10).

2. The bone fixation system according to claim 1, characterized in that: The through hole diameter of the channel screw is 1.5 mm.

3. A tensioner for tibiofibular separation "8" cerclage, comprising a first hinge rod (11) and an adjusting screw rod (12), characterized in that: A threaded hole matching the adjusting screw (12) is provided at the middle of the first hinged rod (11), the threaded hole is perpendicular to the length direction of the first hinged rod (11), and the adjusting screw (12) is inserted into the threaded hole; two ends of the first hinged rod (11) are symmetrically hinged with tensioning plates (13), and the two tensioning plates (13) and the adjusting screw (12) are located in the same plane; a second hinged rod (14) is provided at one end of the adjusting screw (12), and the middle of the second hinged rod (14) is provided with a second hinged rod (14). A through hole with a diameter larger than that of the adjusting screw (12) is provided, and two positioning blocks (15) are fixed on the adjusting screw (12), and the second hinged rod (14) is located between the two positioning blocks (15); the end of the second hinged rod (14) is symmetrically hinged with two connecting rods (16), and the two connecting rods (16) are respectively hinged to the two tensioning plates (13); the opposite sides of the two tensioning plates (13) are provided with a wire clamping mechanism for fixing the ligature steel cable (2) described in claim 1.

4. The tensioner according to claim 3, characterized in that: A wire groove (17) is provided between the end of the tensioning sheet (13) and the wire clamping mechanism.

5. The tensioner according to claim 3, characterized in that: The wire clamping mechanism comprises a bolt (18) fixed on the tensioning sheet (13), a threading hole (19) for the cerclage steel cable (2) to pass through is arranged in the middle of the bolt (18), and a knob clamp (20) is threadedly connected to the bolt (18).

6. The tensioner according to claim 3, characterized in that: A rotating handle (21) is provided at the end of the adjusting screw rod (12) away from the second hinge rod (14).

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