WO2012167729A1

WO2012167729A1 - Torsion-measurable combination-type compression locking device for joint fracture

Info

Publication number: WO2012167729A1
Application number: PCT/CN2012/076544
Authority: WO
Inventors: 徐达强
Original assignee: Xu Daqiang
Priority date: 2011-06-09
Filing date: 2012-06-06
Publication date: 2012-12-13
Also published as: CN102217972B; CN102217972A

Abstract

A torsion-measurable combination-type compression locking device for joint fractures, characterized in that: said device comprises a component (A), a component (B), and a locking bone fixation plate (C). Component (A) is composed of a screw thread (1), a screw thread (2), and a tail portion (4). The screw thread (1) is a tapered screw thread, the screw thread (2) is a straight screw thread, and the tail portion (4) is a prismatic structure. The component (B) is composed of a screw thread (5) and a screw thread (7). The inside of the screw thread (7) is a hollow prismatic hole that extends through screw thread (5). The tail portion (4) of component (A) passes through the inside of the screw thread (5) and the screw thread (7). Component (A) and component (B) are connected my means of the screw thread (2) and the screw thread (5). Component (B) and the locking bone fixation plate (C) are connected by means of the screw thread (7) and the screw thread (8). The pitch of the screw threads (2 and 5) is greater than that of the screw threads (7 and 8). The screw threads (2, 5, 7, and 8) are all straight screw threads. The present invention allows for compression of the bone fracture pieces in the joint while also allowing for excellent angular axial stability, measurable torsion, and pressure on the bone fracture fragments.

Description

Combined pressure locking device for quantifiable torque applied to joint fracture

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fracture internal fixation device, and more particularly to an internal fixation device and system for use in joint fractures. BACKGROUND OF THE INVENTION The current principles of treatment of joint fractures are as follows: Intra-articular fractures require non-invasive anatomical reduction of the articular surface, compression and fixation of the intra-articular fracture block, bone grafting and bone grafting to reconstruct the metaphysis, early postoperative Functional exercise. Reconstruction of the joints of the joints requires protection of the vitality of the soft tissue and the integrity of the capsule. The metaphyseal fracture block does not require anatomic reduction, as long as the axis of the limb is maintained, allowing for controlled early functional exercise through the relative stability of the overall structure.

Currently designed according to this principle and used in the clinical mainstream is the combination of locking compression plate and multiple cancellous bone screws or the combination of locking plate and multiple cancellous bone screws.

The principle of assisting the reduction of intra-articular fractures by cancellous bone screws, and the fixation and strengthening of intra-articular fractures are as follows: Cancellous bone screws rely on bone plates or spacers to apply pressure to the cortical bone to assist in the reduction of intra-articular fractures and joints. The internal fracture block forms a compression and fixation effect, wherein the cancellous bone screw has no threads at the tail. The locking screw and the locking bone plate have angular stability under the joint surface, support the dry end, and prevent the joint surface from being lost in the long-term height. The threaded screw hole inside the locking bone plate is combined with the screw tail, and the screw tail is threaded. .

Current mainstream treatment methods and related medical devices used have the following disadvantages:

1. The problem of initial fixation failure and long-term fixation failure is used to assist the reduction of intra-articular fractures, the compression of the intra-articular fracture block and the fixation of the cancellous bone screws. The so-called initial fixation failure means that the torsion force required to screw the cancellous bone screw into the intra-articular fracture block depends on the operator's experience and is usually over-tightened, resulting in plastic deformation of the screw, fracture or between the cancellous bone and the thread. The interface damage causes the internal fixation to fail. The so-called long-term fixed failure means that the cancellous bone screw can not form a locked whole with the bone plate, and can not provide angular axial stability. After a certain period of time, there is looseness of the screw under the action of bad stress, which makes the internal fixation invalid.

2. Although the locking screw can be locked with the locking bone plate, it can not assist the reduction of the intra-articular fracture block and provide the compression effect. At the same time, the single locking screw has less pull-out force in the cancellous bone than the single cancellous bone screw. Therefore, it is often necessary to use a locking screw for use with a cancellous bone screw, a locking bone plate or a locking compression bone plate, but this still avoids the associated disadvantages and the number of screws implanted in the body is greatly increased.

3. When treating joint fractures, it is used to assist the reduction of intra-articular fractures, to achieve intra-articular fracture block compression and strong The fixed cancellous bone screw does not form a unit with the locking screw system that supports and reconstructs the metaphyseal end. It is generally necessary to implant more internal fixations to achieve the principle of treatment of joint fractures, but the implantation of more internal fixations will lead to greater surgical trauma, higher medical costs and the like. These shortcomings are particularly prominent in the treatment of partial articular fractures. Currently, the locking bone plates used in the clinical mainstream of partial joint fractures are longer than the fracture area, the bone plates extend to the backbone, and the fractures of the bones also need to be screwed in. Screws lead to greater surgical trauma, while longer bone plates and poor bone attachment may also result in decreased mechanical effects of the internal fixation system and soft tissue complications.

4. The torque required to screw the cancellous bone screw into the intra-articular fracture block depends on the operator's experience, so there is a slope of the learning curve, which is not conducive to the formation of quantitative criteria for this technique. The accumulation of experience depends on the experience of failure. . SUMMARY OF THE INVENTION The technical problem to be solved by the present invention is to provide a device capable of achieving reduction, compression and strong fixation of an intra-articular fracture block, and having good angular axial stability, thereby avoiding the looseness of the screw due to sequential looseness. Internal fixation long-term fixation failure; Quantify the torque required to screw into the intra-articular fracture block device, effectively protect the interface between the device and the cancellous bone while assisting the reduction, compression and strong fixation of the intra-articular fracture block, avoiding internal fixation Initial fixation failure; Quantify the pressure between the intra-articular fracture blocks so that the fractured articular surface hyaline cartilage can achieve true healing within the proper pressure range.

In order to solve the above technical problems, the present invention provides the following technical solution, a combined compression locking device for quantifiable torque applied to joint fractures: comprising a component, a component B and a locking bone plate C, the component A is threaded 1, threaded 2 and the tail portion 4, the thread 1 is a tapered thread, the thread 2 is a coaxial thread, the tail portion 4 is a prismatic structure, the assembly B is composed of a thread 5 and a thread 7, and the inside of the thread 7 is a hollow prismatic hole, which is threaded 5 Throughout, the tail 4 of the assembly A can pass through the internal hollow portion of the thread 5 and the thread 7, the assembly A and the assembly B are connected to the thread 5 by the thread 2, and the thread 7 of the assembly B and the locking plate C is connected to the thread 8, The pitch of the threads 2, 5 is greater than the pitch of the threads 7, 8, and the threads 2, 5, 7, 8 are coaxial threads.

A preferred embodiment of the combined compression lock device for quantifiable torque applied to joint fractures of the present invention, wherein: the thread depth and pitch of the component A thread 1 is greater than the thread depth and pitch of the thread 2.

A preferred embodiment of the combined compression lock device for quantifiable torsion applied to joint fractures according to the present invention, wherein the thread 2 of the assembly A and the tail portion 4 are connected by a rod 3, the rod 3 The diameter is smaller than the diameter of the thread 5 and the aperture of the hollow prismatic hole inside the thread 7.

A preferred embodiment of the combined compression lock device for quantifiable torque applied to joint fracture according to the present invention, wherein: a portion of the thread 5 of the assembly B and a hollow prismatic hole inside the thread 7 are provided Excessive snail The knurled portion 6, the thread 5 portion and the excessively unthreaded portion 6 have a larger diameter than the tail portion 4 and the diameter of the rod 3.

A preferred embodiment of the combined compression locking device for quantifiable torsion applied to joint fractures according to the present invention, wherein: the tail 4 prismatic structure matches the inner sleeve of the composite sleeve, the component B The hollow prismatic bore inside the thread 7 matches the outer sleeve of the composite sleeve.

The composite sleeve for the special tool is divided into inner and outer sleeves: the inner sleeve passes through the hollow portion in the assembly B, and the tail portion 4 of the assembly A is sleeved; the outer sleeve is connected with a torsion device such as a torque wrench, and The hollow prismatic holes inside the threads 7 of the assembly B are matched.

The beneficial technical effects of the present invention include: 1. The distance difference caused by the coaxial rotation of the threads 7, 8 and the threads 2, 5 assists the reduction of the intra-articular fracture block, the formation of the intra-articular fracture block and the strong fixation effect, and the thread of the component B. 7 The fixed connection with the thread 8 of the locking plate C makes the entire system form a locked unit with good angular axial stability. Thereby achieving the "reset, compression and strong fixation of the intra-articular fracture block" and the "axial angle stability under the joint surface, supporting and reconstructing the metaphyseal end" integration, and at the same time improving the overall pull-out force of the whole device; 2. With the device of the present invention, the torque required for the device for screwing into the intra-articular fracture block can be accurately calculated by means of the instrument, and there is no slope of the learning curve, which is conducive to the formation and popularization of the quantitative standard of the technology; Quantify the pressure between the intra-articular fractures, so that the fractured articular hyaline cartilage can achieve true healing within the proper pressure range. 4. Compared with current mainstream medical technology and devices, less internal fixation is used. The principle of treatment of joint fracture can be realized in vivo, and the surgical trauma is smaller and the medical cost is greatly reduced. 5. When the part of the joint fracture requiring surgery is treated, the device of the present invention requires a shorter length of the locking bone plate to reduce the surgical wound. The shorter locking plate can better attach to the bone, further improving the mechanical stability of the whole device. Qualitative, effectively reduce soft tissue complications caused by poor attachment of the bone plate. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic view showing the state of use of the device of the present invention.

Figure 2 is a schematic diagram of component A.

Figure 3 is a schematic view of the end face of the tail portion 4 of the assembly A.

Figure 4 is a partial schematic view of component B.

Figure 5 is a partial cross-sectional view of the component B.

Figure 6 is a schematic view of the end face of the end of the assembly B.

Figure 7 is a perspective view of the locking bone plate C.

Figure 8 is a schematic view showing the connection of the component A, the component B and the locking bone plate C. FIG. 9 is a schematic diagram of the connection of component A and component B.

Figure 10 is a perspective view of component B.

Figure 1 is a schematic view of a composite sleeve.

Figure 12 is a schematic illustration of the installation of the apparatus of the present invention using a composite sleeve. BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be further described in detail below with reference to the accompanying drawings.

As shown in Fig. 1, Fig. 8, and Fig. 9, the combined compression locking device for quantifiable torsion applied to joint fracture of the present invention is divided into three parts: component A, component B and locking plate C. 1 and 12 are schematic views of a composite sleeve and a schematic view of the assembly using a composite sleeve, wherein the composite sleeve includes an inner sleeve D and an outer sleeve 巳.

As shown in Fig. 2 and Fig. 3, the component A is composed of a thread 1, a thread 2, a rod 3, and a tail portion 4, and the tail portion 4 is a prismatic structure such as a hexagonal prism or the like. Regardless of the shape of the tail 4, it is smaller than the hole inside the thread 5 or 7 of the component B, and can pass through the hole inside the thread 5 or 7 with a certain gap so that the sleeve of the composite sleeve can be fixed. Tail 4. Thread 1 is similar to the thread design of a standard cancellous bone screw with a thread depth and pitch that is larger relative to the thread 2. When in use, the thread 1 is screwed into the contralateral intra-articular fracture block, at which point component A is anchored to the contralateral intra-articular fracture block. Thread 1 should be threaded through the fracture line and fully into the contralateral intra-articular fracture block. Thread 1 provides better pull-out resistance than locking screw, which is similar to cancellous bone screws. The thread depth and pitch of the thread 2 is less than the thread depth and pitch of the thread 1, and the thread 2 is part of the reduction of the intra-articular fracture block and the effect of compression between the fracture blocks. The rod 3 mainly increases the length variation of the component A. This part can also be replaced by the thread 2, and the length of the thread 2 design can also solve the length problem. The tail portion 4 is a prismatic structure, such as a hexagonal prism, on the one hand, the assembly A can be screwed into the fracture block, and on the other hand it can be matched with the inner sleeve of the composite sleeve to fix the assembly A.

As shown in Figures 4, 5, 6, and 10, the assembly B is composed of a thread 5, an excessively unthreaded portion 6, and a thread 7, and the interior of the assembly B is hollow. The function of the over-threadless portion 6 is to provide a change in the length of the assembly B, which can also be designed as a thread 5. Setting the excessively unthreaded portion 6 can provide a potential mechanical advantage. The thread 5 has the same pitch and thread depth as the thread A of the assembly A, and the connection between the thread 2 and the thread 5 enables the connection of the assembly A to the assembly B. The pitch of the thread 7 is less than the pitch of the thread 5, which is part of the connection assembly B and the locking plate C, and is also part of the reduction of the intra-articular fracture block and the effect of the compression of the fracture block. The inside of the thread 7 is a hollow prismatic hole, such as a hexagon socket or the like, and the assembly B can be used to connect the component B to the component A and the locking plate. The diameter of the hollow prismatic hole inside the thread 7 is larger than the diameter of the tail portion 4 of the assembly A, so that the inner sleeve of the composite sleeve can pass through the hollow in the assembly B In part, the assembly A is held while the outer sleeve of the composite sleeve rotates the assembly B.

As shown in FIGS. 1 and 7, the shape of the locking bone plate C can be various, and is provided with a thread 8 having the same pitch and thread depth as the thread 7, and the connection between the thread 7 and the thread 8 can realize the assembly B and Lock the lock between the bone plates C.

The so-called ipsilateral intra-articular fracture block refers to the side that is in contact with the locking plate C. The so-called contra-articular fracture block refers to the fracture block corresponding to the ipsilateral intra-articular fracture block.

The use of a combined compression lock device for quantifiable torsion applied to joint fractures according to the present invention in a specific procedure:

Step 1: According to the standard surgical procedure, disinfect the shop and expose the fracture according to the standard surgical approach, reset and temporarily fix the fracture with Kirschner wire or reduction forceps, and confirm that the reduction is good;

Step 2: Fix component A first: Use a surgical special rotor to punch the ipsilateral fracture block to the contralateral intra-articular fracture block, and use the inner sleeve of the composite sleeve that matches the tail of component A to assemble component A. The thread 1 is screwed into the contralateral intra-articular fracture block. The thread 1 should be screwed through the fracture line and fully into the contralateral intra-articular fracture block. At this time, the component A and the contralateral intra-articular fracture block are anchored. Thread 1 provides a pull-out resistance that is superior to a locking screw and is similar to a cancellous bone screw.

Step 3: The bone plate C should be locked by a corresponding device, such as a pelvic reduction forceps or screw, to avoid the horizontal movement or rotation of the locking plate C, so that the locking plate C is tightly attached to the intra-articular fracture block. The surface of the cortical bone. The outer sleeve of the composite sleeve is connected to a torsion device such as a torque wrench so that the torque value used can be detected at any time. Passing the inner sleeve of the composite sleeve through the hollow portion of the assembly B, sheathing the tail portion 4 of the assembly A to fix the assembly A, and then rotating the outer sleeve of the composite sleeve, so that the assembly B and the locking bone plate C and assembly A is constantly tightened between A. In this process, during the process of screwing the thread 7 of the assembly B into the thread 8 of the locking plate C by means of the outer sleeve of the composite sleeve, the thread 5 of the assembly B and the thread 2 of the assembly A also rotate with each other. . When the threads 7 and 8 are rotated one turn, the threads 2 and 5 are also rotated one turn, but since the pitch of the threads 7 and 8 is smaller than the pitch of the threads 2 and 5, the threads 7 and 8 are rotated one turn forward by less than the thread 2 and 5 Turn a circle forward. Since the component A has been fixed, the difference in the distance between the threads 7, 8 and the threads 2, 5 will cause the component B to drive the locking plate C together toward the component A, which eliminates the intra-articular fracture. The gap and the effect of compression between the intra-articular fractures. Basic medical research and clinical practice have proved that the compression of the intra-articular fracture block and the pressure value can be controlled within the proper range is one of the basic factors to achieve the healing of the articular surface hyaline cartilage. Therefore, when using a torque wrench to twist the composite sleeve, pay attention to the value of the applied torque. When the proper value is reached, for example, 2500 N, the force is stopped, so that the pressure required between the compression of the intra-articular fracture block can be quantified. Twist required for an intra-articular fracture The force is more conducive to the true healing of the hyaline cartilage on the articular surface.

Firstly, the component A and the contralateral intra-articular fracture block are anchored, and the inner sleeve of the composite sleeve is used to fix the component A, and then the component B is connected with the locking bone plate C and the component A to achieve the following purposes: Rotation occurs during this process, causing the thread 1 to cut adjacent to the cancellous bone, effectively protecting the interface between the thread 1 of the component A and the cancellous bone, preventing initial fixation failure. At the same time, the end of the component B and the locking plate C are also threadedly locked so that the entire device has good angular axial stability, avoiding the long-term fixing failure caused by the sequential looseness of the screw.

Step 4: Cut the component B through the relevant device above the portion of the locking plate C.

Step 5: According to the needs of the operation, a plurality of the screw devices of the present invention can be screwed into the appropriate screw holes of the locking bone plate by the same procedure; according to the surgical needs, other types of screws can also be screwed into the appropriate screw holes of the locking bone plate. , for example, a locking screw or a standard cortical screw.

Step 6: Re-perspectively confirm the fracture reduction and internal fixation position, flush the wound and suture it to the skin after hemostasis.

The unique design of the device of the present invention assists in the reduction of the intra-articular fracture block, simultaneously achieves the intra-articular fracture compression fixation and the angular axial stability, quantifies the pressure between the intra-articular fracture blocks; and can quantify the intra-articular fracture block The required torque to prevent the device from being over-tightened or too loose, resulting in initial failure of the internal fixation; also improving the pull-out resistance of the device of the present invention in the cancellous bone, further improving the fixation of the internal implant system Reliability.

Therefore, the device is in the auxiliary joint fracture block, and the intra-articular fracture block is firmly pressed and fixed, and can be locked with the bone plate to provide axial angle stability, and the pull-out resistance is stronger than the current locking screw. Effectively improve the reliability of the entire fixed fracture system, reducing the number of plants required for the entire fixed fracture system, reducing medical costs and patient suffering. Especially in the treatment of partial joint fractures, the locking plate C does not need to extend too much to the backbone, and the unbroken bone does not need to be screwed into too many screws, so the length of the locking plate C needs to be small, which is beneficial to Locking the attachment of bone plate C to the bone further improves the mechanical stability of the entire fixed fracture system, reduces surgical trauma, and effectively reduces soft tissue complications caused by poor attachment of the bone plate.

It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and the present invention is not limited thereto. Although the present invention is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be Modifications or equivalents are intended to be included within the scope of the appended claims.

Claims

Claim

A combined compression lock device for quantifiable torque applied to joint fractures, comprising: a component (A), a component (B) and a locking bone plate (C), the component (A) is threaded (1) , thread (2) and tail (4), thread (1) is tapered thread, thread (2) is coaxial thread, tail (4) is prismatic structure, component (B) is threaded (5) and Thread (7) is formed, the inside of the thread (7) is a hollow prismatic hole, which penetrates with the thread (5), and the tail (4) of the component (A) can pass through the internal hollow of the thread (5) and the thread (7) In part, component (A) and component (B) are connected to thread (5) by thread (2), and thread (7) and thread (8) of component (B) and locking plate (C) are connected, thread (2) ),

The pitch of (5) is larger than the pitch of threads (7) and (8), and the threads (2), (5), (7), and (8) are coaxial threads.

2. The combined pressure locking device for quantifiable torque applied to joint fracture according to claim 1, wherein: the thread depth and the pitch of the component A thread (1) are greater than the thread depth and pitch of the thread (2). .

3. The combined compression lock device for quantifiable torque applied to joint fracture according to claim 1, wherein: the thread (2) and the tail portion (4) of the assembly (A) pass through a rod ( 3) Connection, the diameter of the rod (3) is smaller than the diameter of the thread (5) and the diameter of the hollow prismatic hole inside the thread (7).

4. A combined compression lock device for quantifiable torque applied to joint fractures according to claim 1 or 3, characterized in that: the thread (5) portion of the assembly (B) and the thread (7) interior An excessively unthreaded portion (6) is provided between the hollow prismatic holes, and the diameter of the thread (5) and the excessively unthreaded portion (6) is larger than the diameter of the tail portion (4) and the rod (3).

5. The combined compression lock device for quantifiable torque applied to joint fracture according to claim 1, wherein: the tail (4) prismatic structure matches the inner sleeve of the composite sleeve, The hollow prismatic bore inside the thread (7) of assembly B matches the outer sleeve of the composite sleeve.