Background
With the rapid development of material science and biomechanics, the performance of artificial ligaments is closer to natural ligaments. Currently, artificial ligaments mainly by LARS are widely used in damaged joints.
The firm bond between the artificial ligament and the host bone is the key to influence the ligament replacement effect and the service life. The fixing mode of current artificial ligament mainly includes: the axial screw extrusion type and the transverse screw suspension type. The axial screw extrusion type adopts metal screws to extrude the artificial ligament in the bone tunnel to form fixation, the scheme reduces the contact area between the ligament and the bone tunnel, reduces the internal space of the ligament due to the extrusion of the screw on the ligament, influences the growth of autologous tissues, easily loosens the screw in the long-term bone tunnel, and finally causes the failure of the artificial ligament; the transverse screw perforation type is fixed by adopting a transverse screw, so that the contact area of the ligament and the bone tunnel can be increased, the growth of osteocytes is facilitated, but the transverse screw perforation type needs transverse holes, and the damage is increased.
Meanwhile, the two modes require that a penetrating hole is formed in the joint bone, so that the joint is greatly damaged, and the recovery of a patient is not facilitated; in addition, the length before and after fixation cannot be finely adjusted, so that the ideal length is difficult to achieve, the actual function of the ligament is affected, and even the function is lost.
In view of the above problems, there is a need to improve the structure of the existing artificial ligament, optimize the fixing manner thereof, and perform fine adjustment. The clinical application proves that the tantalum is an orthopedic implant with ideal biocompatibility, and particularly the porous tantalum has a porous structure meeting the requirement of interface bone ingrowth and good mechanical properties with the elastic modulus close to that of host bones, so that the porous tantalum is more and more widely applied in the fields of bone defect repair and joint replacement in recent years. The utility model discloses introduce ligament bone end joint portion with porous tantalum, utilize its bone to grow into the characteristic and strengthen bone end joint strength, utilize its mechanical properties to reduce the stress of deciding the mode in the present country and shelter from, solve the ligament body simultaneously and firmly combine and the adjustable characteristic of ligament body length with porous tantalum, this utility model has the significance to the success rate that improves artifical ligament, the long-term validity who keeps artifical ligament.
SUMMERY OF THE UTILITY MODEL
In view of this, the utility model aims at providing an artificial ligament to solve the big, the length of wound that current fixed mode exists and can not accurate regulation and the insecure lasting problem of bone end fixing.
The utility model discloses a following technical scheme realizes:
the artificial ligament comprises a ligament body and a bone anchor component, wherein the bone anchor component comprises a first anchor and a second anchor which are respectively arranged at two ends of the ligament body, and a length adjusting mechanism arranged between the first anchor and the ligament body, the first anchor is rotatably connected with the ligament body through the length adjusting mechanism, and the first anchor and the second anchor are respectively provided with a connecting thread used for being connected with a bone canal and a driving flange used for rotating and driving.
Further, the length adjusting mechanism comprises a fixed body and a rotating body, the fixed body comprises a hollow pipe section and a sphere section which is coaxially arranged at one end of the hollow pipe body and has a diameter larger than that of the hollow pipe section, the other end of the hollow pipe body is connected with the ligament body, the rotating body is a cylinder, an embedding hole which is matched with the fixed body in shape is arranged in the cylinder, the fixed body is rotationally fixed in the embedding hole, an external thread is arranged outside the cylinder, and an internal thread which is screwed with the external thread is arranged in the first anchor.
Further, the internal thread is a Shibija thread.
Furthermore, a connecting body used for being wound and fixed with the ligament body is arranged in the ball body.
Furthermore, the connecting body is a sphere or a strip body with a net structure, and the wiring harness of the ligament body is woven and fixed in meshes of the sphere or the strip body.
Further, the driving flange has a regular polygonal shape.
Further, the surface of all or a certain thickness of the first anchor nail and the second anchor nail is of a pure tantalum or tantalum alloy porous structure.
Furthermore, the front ends of the first anchor and the second anchor are provided with nail-in conical tips.
The beneficial effects of the utility model reside in that:
the utility model can fix the ligament body in the joint cavity through the bone anchor component, only needs to set a small section of hole at the two ends of the joint bone, has small joint damage and quick rehabilitation, avoids the damage of the penetrating hole to the joint bone, and can not rotate relative to the joint bone and shorten the length when fixing; meanwhile, the length of the ligament body can be adjusted through the length adjusting mechanism so as to achieve the most appropriate state, and the natural ligament is replaced functionally.
The utility model discloses introduce ligament bone end joint portion with porous tantalum, utilize its bone to grow into the characteristic and strengthen bone end joint strength, utilize its mechanical properties to reduce the stress of deciding the mode in the present country and shelter from, solve the ligament body simultaneously and firmly combine and the adjustable characteristic of ligament body length with porous tantalum, this utility model has the significance to the success rate that improves artifical ligament, the long-term validity who keeps artifical ligament.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the above description of the present invention, it should be noted that the terms "one side" and "the other side" are used for indicating the position or the positional relationship based on the position or the positional relationship shown in the drawings, or the position or the positional relationship which is usually placed when the product of the present invention is used, only for the convenience of describing the present invention and simplifying the description, but not for indicating or implying that the indicated device or element must have a specific position, be constructed and operated in a specific position, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.
Further, the term "identical" and the like do not mean that the components are absolutely required to be identical, but may have slight differences. The term "perpendicular" merely means that the positional relationship between the components is more perpendicular than "parallel", and does not mean that the structure must be perfectly perpendicular, but may be slightly inclined.
As shown in fig. 1 to 8, the artificial ligament of the present embodiment includes a ligament body 1 and a bone anchor assembly 2, and the structure and the components of the ligament body of the present embodiment are not specially modified or required, and may be an LARS ligament in the existing clinical application, a bionic biomaterial substitute, a future tissue engineering ligament, or the like. The bone anchor component of this embodiment includes first anchor 12, second anchor 13 and length adjustment mechanism 3, first anchor and second anchor set up respectively at ligament body both ends, and all be provided with on first anchor, the second anchor and be used for the connecting thread 4 and be used for rotary drive's drive flange 5 with bone way is connected, through the rotatory fixing on bone way of drive flange drive first anchor or second anchor, length adjustment mechanism sets up between first anchor and ligament body, first anchor passes through length adjustment mechanism and ligament body rotatable coupling, thereby when rotatory the fixing, can not make ligament body rotatory winding, shorten actual length and influence its performance.
The length adjusting mechanism of the embodiment comprises a fixed body 6 and a rotating body 7, wherein the fixed body comprises a hollow pipe section 61 and a ball section 62, the ball section is coaxially arranged on one end of the hollow pipe body, the diameter of the ball section is larger than that of the hollow pipe section, and at least part of the ball surface protrudes out of the surface of the hollow pipe body; the rotator is a cylinder, an embedding hole 71 which is matched with the shape of the fixed body is arranged in the cylinder, the fixed body is rotationally fixed in the embedding hole, the surface of the ball body protrudes out of the surface of the tube body, so that a rotary kinematic pair 11 which can not be separated is established between the rotator and the fixed body, the rotator does not drive the fixed body to rotate when rotating, and the other end part of the hollow tube body is connected with the ligament body, so that the ligament body can not rotate when the rotator rotates; meanwhile, the external thread 72 is arranged outside the cylinder, the internal thread 8 which is screwed with the external thread is arranged in the first anchor, and the length of the rotating body which is screwed into the first anchor is adjusted through the screwing of the internal thread and the external thread, so that the length of the ligament body is adjusted, and the effective length of the ligament body is accurately adjusted.
When the device is used, under the guidance of an arthroscope, the joint bones corresponding to the two ends of the damaged ligament in the joint cavity are respectively provided with an anchor bottom hole, then the first anchor and the second anchor are respectively screwed and fixed in the two anchor bottom holes, then the rotating body is screwed in the internal thread of the first anchor, and the rotating body is adjusted to a proper length, so that the ligament replacement is completed.
The length of the anchor bottom hole of the embodiment is matched with the length of the anchor, a penetrating hole is not needed to be formed, the joint damage is small, the rehabilitation is fast, and due to the special spherical kinematic pair, the ligament body cannot rotate relative to the joint bone, and the length cannot be changed; meanwhile, the length of the ligament body can be accurately adjusted through the length adjusting mechanism, so that the artificial ligament can reach the best state, and the natural ligament is really replaced in function.
In practical use, length adjusting mechanisms can be arranged at both ends of the ligament body so as to obtain larger adjusting space.
In this embodiment, the internal threads are Shibija threads. The root of the Shibija thread has a 30-degree wedge-shaped inclined surface, and when the screw is screwed down, the tooth tip of the rotating body is tightly pressed against the wedge-shaped inclined surface of the Shibija thread, so that a large locking force is generated. Can effectively prevent loosening or falling off.
In this embodiment, a connector 9 is disposed in the sphere segment, the connector may be a net structure with a spherical shape, a rectangular shape, a square shape, etc., and the wiring harness of the ligament body is woven and fixed in the mesh of the connector. This embodiment is preferably a sphere, which facilitates engagement with the outer sphere segment, is more resistant to disengagement,
when the connecting body is manufactured, the ligament body is woven on the connecting body, the diameter of the ligament body is larger than that of the pipe body, and then the ball body section is connected with the pipe body. Thus, the ligament body can be firmly connected to the fixing body through the connecting body.
In this embodiment, the outer shape of the driving flange is not limited, and may be a circle having teeth in the circumferential direction, or a regular polygon, which is a regular hexagon in this embodiment.
In this embodiment, the surface of the first anchor and the second anchor, which is the whole or a certain thickness, is pure tantalum, and more preferably, is a tantalum alloy porous structure. The clinical application proves that the tantalum is an orthopedic implant with ideal biocompatibility, and particularly the porous tantalum has a porous structure meeting the requirement of interface bone ingrowth and good mechanical properties with the elastic modulus close to that of host bones, so that the porous tantalum is more and more widely applied in the fields of bone defect repair and joint replacement in recent years.
Porous tantalum is introduced into the ligament bone end combining part, is favorable for bone ingrowth, is similar to natural bone combination and is favorable for improving the combination strength.
In this embodiment, the front ends of the first anchor and the second anchor are provided with a driving conical tip 10. Under the guide of the nail-in conical tip, the anchor can be quickly screwed in, which is beneficial to improving the operation efficiency.
Finally, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the present invention can be modified or replaced by other means without departing from the spirit and scope of the present invention, which should be construed as limited only by the appended claims.