Expansion-force-adjustable anchor with line

Abstract

The invention provides an expansion-force-adjustable anchor with a suture, which is provided with an axis extending from a near end to a far end and comprises a nail body, a nail head and the suture, an expansion part is arranged at the far end of the nail body, a first ratchet part is formed on the inner wall of the expansion part, a second ratchet part is formed on the outer wall of the nail head, and the second ratchet part is used for being matched with the first ratchet part. The first ratchet part and the second ratchet part are arranged in the hollow cavity of the nail body so as to allow the nail head to move towards the near end in the hollow cavity of the nail body and limit the nail head to move towards the far end in the hollow cavity of the nail body, the matching face of the first ratchet part and the second ratchet part is in a necking shape towards the near end along the shaft, and the first ratchet part and the second ratchet part are matched. The nail head can be limited to at least two positions in the hollow cavity of the nail body along the axis, and a smooth part is formed between the first ratchet part and the far end of the expansion part on the inner wall of the expansion part. According to the invention, the smooth part is softer relative to the first ratchet part, and can be inwards extruded and deformed by surrounding cancellous bones, so that the cancellous bones are prevented from being excessively extruded and damaged.

Description

Technical Field

[0001] The invention relates to the field of orthopedic surgical instruments, and in particular to a wire anchor with adjustable expansion force. Background Art

[0002] The wire anchor is used to suture tendons in orthopedic surgery. During surgery, the nail body is screwed into the pre-drilled hole of the bone joint, and the suture is also fixed in the pre-drilled hole of the bone joint by the nail body. One or both ends of the suture are sutured to the tendon, thereby fixing the tendon and the bone joint together. For the elderly or osteoporosis patients, due to their low bone density, it is easy for the nail body of the anchor to be not firmly fixed in the pre-drilled hole.

[0003] To solve this problem, the prior art proposes a wire anchor with a tightening function. For example, the wire anchor disclosed in patent CN202311179176.3 includes an anchor body and an expander. When in use, the anchor body is first inserted into the bone, and then the expander is inserted into the inner hole of the anchor body from the proximal end. The expander is used to squeeze the expansion structure at the tail of the anchor body toward the bone, thereby increasing the fixing force between the anchor and the bone. Although this technology can be applied to different bone densities, since the expansion structure is located at the proximal end of the anchor, that is, the tightening force acts on the cortical bone area, it is easy to cause cortical bone cracking, and additional supporting equipment is required to insert the expander into the inner hole of the anchor body during operation.

[0004] The wire anchor disclosed in patent CN202310330660.5 includes an expansion member, a first threaded member, and a second threaded member. When in use, the first threaded member is screwed, and the second end of the expansion member is squeezed by the squeezing part, thereby increasing the fixing force between the anchor and the bone. Although this technology avoids providing a tightening force in the cortical bone area, it still requires additional matching equipment to screw the first threaded member.

[0005] The anchor with thread disclosed in patent CN202210863563.8 includes a nail body and a nail head. During use, the suture is pulled to pull the nail head into the four expansion pieces of the nail body, and the four expansion pieces are radially opened outward, thereby improving the implantation strength of the anchor. Although this technology does not require the use of additional supporting instruments to perform the tightening action, after a period of use, slippage occurs between the nail head and the expansion piece, causing the expansion piece to expand outward and relax, and the end of the expansion piece is turned outward, which is easy to cause cancellous bone damage. Summary of the invention

[0006] The invention provides a wire anchor with adjustable expansion force.

[0007] Specifically, the present invention is achieved through the following technical solutions: An embodiment of the present invention provides a tension-adjustable wire anchor having an axis o extending from a proximal end to a distal end. The tension-adjustable wire anchor comprises: The nail body has a threaded portion on the outside and an inner wall forming a hollow cavity, a tightening portion is provided at the distal end of the nail body, and the inner wall of the tightening portion forms a first ratchet portion; The nail head is provided with a hooking portion, and the outer wall of the nail head forms a second ratchet portion, the second ratchet portion is used to cooperate with the first ratchet portion, so as to allow the nail head to move toward the proximal end in the hollow cavity of the nail body, and to limit the nail head from moving toward the distal end in the hollow cavity of the nail body; The suture is connected to the nail head through the hook part; The mating surfaces of the first ratchet portion and the second ratchet portion are constricted toward the proximal end along the axis o, and the first ratchet portion and the second ratchet portion cooperate to limit the nail head to at least two positions in the hollow cavity of the nail body along the axis o; Furthermore, the expansion portion forms a smooth portion between the first ratchet tooth and a distal end of the expansion portion.

[0008] In some embodiments, the expansion portion of the nail body is in the shape of petals separated by a narrow groove extending along the axis o.

[0009] In some embodiments, the narrow groove includes a first narrow groove and a second narrow groove distributed along the circumferential direction of the outer wall of the expansion portion, the first narrow groove extends over the entire expansion portion, and the second narrow groove extends over only the smooth portion.

[0010] In some embodiments, a hole is formed at one end of the first slot close to the proximal end, the hole penetrates the outer wall and the inner wall of the nail body, and the diameter of the hole is greater than the width of the first slot.

[0011] In some embodiments, the second slot is flared toward the distal end along the axis o.

[0012] In some embodiments, the first ratchet portion has a plurality of ratchet structures.

[0013] In some embodiments, the second ratchet portion has at least one pair of ratchet structures.

[0014] In some embodiments, a first limiting portion is provided on the inner wall of the nail body located on the side of the first ratchet portion close to the proximal end, and a second limiting portion is provided on the outer wall of the nail head located on the side of the second ratchet portion close to the proximal end. The first limiting portion cooperates with the second limiting portion to limit the extreme position of the nail head moving toward the proximal end in the hollow cavity of the nail body.

[0015] In some embodiments, the nail head is provided with a head, a middle part and a tail part, the second ratchet part is arranged on the outside of the head part, and the second limiting part is formed at the transition between the middle part and the tail part.

[0016] In some embodiments, the proximal end of the nail body is provided with an inner polygon for inserting a tool having a matching contour.

[0017] According to an embodiment of the present invention, the suture is connected to the nail head through the hook portion, and the suture is passed through the hollow cavity of the nail body. The suture only needs to be pulled from the proximal end of the nail body to pull the nail head from the distal end to the proximal end relative to the nail body. Since the matching surfaces of the first ratchet portion and the second ratchet portion are constricted, as the nail body moves, the nail body squeezing and expanding portion is radially expanded, thereby improving the fixation firmness of the nail body and the bone joint; since the first ratchet portion and the second ratchet portion can cooperate to limit the nail head to at least two positions in the hollow cavity of the nail body along the axis, the nail body can be suitable for the firm fixation of at least two bone joints with different bone densities, and ensure that there is no slippage between the nail head and the nail body during long-term use, thereby maintaining the stability of the firm fixation between the nail body and the bone joint; in particular, the smooth portion is softer than the first ratchet portion, and can be squeezed and deformed inward by the surrounding cancellous bone, thereby avoiding excessive squeezing damage to the cancellous bone.

[0018] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0020] Figure 1 is a schematic diagram of a wire anchor with adjustable tensioning force in one embodiment of the present invention; Figure 2 yes Figure 1 A partial enlarged view of the middle A; Figure 3 is a schematic diagram of a nail head in one embodiment of the present invention; Figure 4 is a cross-sectional view of a wire anchor with adjustable tensioning force in one embodiment of the present invention; Figure 5 yes Figure 4 A partial enlarged view of point B in the middle; Figure 6 is a cross-sectional view of a nail head in one embodiment of the present invention; Figure 7 4 is a cross-sectional view of a nail body in one embodiment of the present invention.

[0021] Reference numerals: 10: nail body; 11: threaded portion; 12: cavity; 121: first limiting portion; 13: tightening portion; 131: first ratchet portion; 132: smooth portion; 133: first slot; 134: second slot; 135: hole; 14: inner polygon; 20: nail head; 21: hooking portion; 22: second ratchet portion; 23: second limiting portion; 30: Suture. DETAILED DESCRIPTION

[0022] The present invention will now be discussed with reference to several embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present invention, rather than implying any limitation on the scope of the present invention.

[0023] As used herein, the term "including" and its variants are to be interpreted as open-ended terms meaning "including but not limited to"; the terms "embodiment" and "one embodiment" are to be interpreted as "at least one embodiment"; the term "another embodiment" is to be interpreted as "at least one other embodiment"; the terms "first", "second", etc. may refer to different or the same objects; the term "setting" is not limited to direct connection or indirect connection, nor is it limited to a specific connection method. Other explicit and implicit definitions may also be included below.

[0024] In the following description, some specific numerical values ​​or numerical ranges may be involved. It should be understood that these numerical values ​​and numerical ranges are merely exemplary, and they may be helpful in putting the idea of ​​the present invention into practice. However, the description of these examples is not intended to limit the scope of the present invention in any way. According to specific application scenarios and requirements, these numerical values ​​or numerical ranges can be set separately.

[0025] As described above, after a period of use, the prior art wire anchor has a slippage between the nail head 20 and the expansion piece, causing the expansion piece to expand and relax outward, and the end of the expansion piece is turned outward, which can easily cause cancellous bone damage. The wire anchor with adjustable tension force proposed in the embodiment of the present invention at least partially solves the above problems. Figures 1 to 7 The structure and working principle of the wire anchor with adjustable tension force according to an exemplary embodiment of the present invention are described below. Figure 1-7 As shown, the wire anchor with adjustable tensioning force of an embodiment of the present invention generally comprises a nail body 10, a nail head 20 and a suture 30. The nail body 10 is used to be anchored in the cancellous bone of the joint bone, the nail head 20 is fixed at the bottom of the pre-drilled hole by the nail body 10, and the suture 30 is connected to the nail head 20. By pulling the suture 30 proximally, the nail head 20 can be pulled together to move, so that the nail head 20 and the tensioning portion 13 of the nail body 10 are tensioned at different gears.

[0026] The nail body 10 is cylindrical as a whole, and has an axis o extending from the proximal end to the distal end. A hollow cavity 12 is formed inside the nail body 10 for the suture 30 to pass through the cavity 12. A threaded portion 11 is provided outside the nail body 10, and the nail body 10 is screwed into the pre-drilled hole of the joint bone through the threaded portion 11 and fixed to the cancellous bone. In the embodiment of the present invention, the end of the nail body 10 close to the nail head 20 is defined as the "distal end", and the end of the nail body 10 away from the nail head 20 is defined as the "proximal end".

[0027] The area near the distal end of the nail body 10 is set as an expansion part 13. The area where the expansion part 13 is located can deform along the radial direction of the nail body 10, especially can be stretched outward by the nail head 20, so as to achieve expansion between the wire anchor and the cancellous bone. The reason why the expansion part 13 can be deformed is that the nail body 10 is made of a material with deformation characteristics, especially the nail body 10 is made of a material with deformation characteristics in the area of ​​the expansion part 13, so that the expansion part 13 can be squeezed and deformed.

[0028] The deformation of the expansion part 13 can also be caused by the structure. In one embodiment, the nail body 10 is provided with a first slot 133 extending along the axis o near the distal end region. The number of the first slots 133 can be one or more. The multiple first slots 133 are distributed along the circumference of the nail body 10. The first slots 133 are used to form the nail body 10 into a petal shape, so that the expansion deformation can be achieved under the action of the opening force of the nail head 20. In the embodiment of the present invention, the length dimension of the first slot 133 in the direction of the axis o is defined as the dimension of the expansion part 13 in the direction of the axis o.

[0029] In one embodiment, a hole 135 is formed at one end of the first slot 133 near the proximal end, and the hole 135 penetrates the outer wall and the inner wall of the nail body 10. The diameter of the hole 135 is set to be larger than the width of the first slot 133, which is equivalent to enlarging the size of the root of the first slot 133 at the proximal end, which is beneficial to reducing the structural strength of the expansion part 13, improving the deformability of the expansion part 13, and at the same time reducing the local stress concentration at the root of the first slot 133 at the proximal end, thereby avoiding petal-like cracking during the expansion process.

[0030] In one embodiment, the inner wall of the expansion part 13 forms a second ratchet part 22, and the second ratchet part 22 is composed of at least two ratchet structures arranged along the axis o, so that the nail head 20 can be locked with the expansion part 13 in at least two gears, that is, two different sizes of radially outward expansion forces of the expansion part 13 are achieved. For example, Figure 4 and 5 As shown, the number of ratchet structures of the second ratchet portion 22 is 6, which can achieve six levels of expansion force adjustment, and is conducive to adapting to the expansion of cancellous bones with different bone densities.

[0031] A smooth portion 132 is formed in the distal area of ​​the tightening portion 13 of the nail body 10, and the outer wall and the inner wall of the smooth portion 132 are both set to be smooth, that is, the outer wall of the smooth portion 132 does not form the threaded portion 11, and the inner wall of the smooth portion 132 does not form the second ratchet portion 22, so that the smooth portion 132 has a lower structural strength. Therefore, during the expansion of the tightening portion 13 relative to the cancellous bone, the smooth portion 132 located closer to the distal end has the maximum expansion compression strength with the cancellous bone, which can make the smooth portion 132 deform and shrink radially inward under this compression strength, thereby reducing damage to the cancellous bone.

[0032] In one embodiment, a second slot 134 is provided on the smooth portion 132 along the axis o, and the extension length of the second slot 134 corresponds to that of the smooth portion 132, thereby improving the inward contraction deformation of the smooth portion 132. Figure 2 and 7 As shown, the second slot 134 extends from the terminal position of the threaded portion 11 to the distal end of the nail body 10 .

[0033] According to the embodiment of the present invention, the length of the first slot 133 for allowing the expansion portion 13 to deform radially outward is longer than that of the second slot 134. The slot portion of the first slot 133 located in the smooth portion 132 and the second slot 134 as a whole can provide the smooth portion 132 with an effect of improving the ability to shrink and deform inward. Since the first slot 133 and the second slot 134 cannot completely overlap in the circumferential direction, the slot portion of the first slot 133 located in the smooth portion 132 can also shrink the smooth portion 132 at the circumferential position, thereby ensuring that the shrinkage deformation direction of the smooth portion 132 is more comprehensive. For example, Figure 2 As shown, the two first slots 133 are distributed at 180 degrees, and the two second slots 134 are cross-distributed between the two first slots 133 , that is, the first slots 133 and the second slots 134 evenly divide the smooth portion 132 into four petals, ensuring balanced contraction of the smooth portion 132 .

[0034] In one embodiment, the second narrow groove 134 is configured to be flared along the axis o toward the distal end, that is, the opening near the distal end is larger. Since the smooth portion 132 has a smaller dimension in the direction of the axis o, the flared design can ensure that the smooth portion 132 is more easily squeezed inwardly and contracted, thereby reducing damage to the cancellous bone.

[0035] The nail head 20 is used to expand the expansion part 13 at different gears. To this end, the outer wall of the nail head 20 is formed with a second ratchet part 22 that cooperates with the first ratchet part 131. In one embodiment, the nail head 20 is provided with a head, a middle part and a tail part, the second ratchet part 22 is formed on the outer peripheral wall of the head, and a second limit part 23 is formed between the middle part and the tail part.

[0036] In one embodiment, the nail head 20 has a conical outer periphery, and the second ratchet portion 22 is arranged along the conical outer periphery, so that the mating surface between the first ratchet portion 131 and the second ratchet portion 22 is in a constricted shape. As the nail head 20 moves toward the proximal end along the axis o, the expansion range of the tightening portion 13 by the nail head 20 increases, that is, the tightening force of the tightening portion 13 on the cancellous bone is greater. For example, Figure 6As shown, the angle a between the mating surface (shown by the dotted line in the figure) and the axis o can be 5-8 degrees, so as to achieve an optimal balance between the pulling force required for the suture 30 to pull the nail body 10 and the expansion force generated by the deformation of the expansion portion 13 caused by the nail body 10.

[0037] In one embodiment, the ratchet structures of the first ratchet portion 131 and the second ratchet portion 22 are in opposite directions, so that the first ratchet portion 131 and the second ratchet portion 22 cooperate with each other to allow the nail head 20 to move proximally, but restrict the movement of the nail head 20 distally, that is, the nail head 20 is locked with the tightening portion 13 to prevent the nail head 20 from slipping during use, causing the anchor to loosen in the cancellous bone.

[0038] In one embodiment, the number of ratchet structures of the second ratchet portion 22 is at least one, for example, Figure 5 and Figure 6 As shown, the second ratchet portion 22 is formed in two, that is, the two ratchet structures of the second ratchet portion 22 are locked with the two ratchet structures of the first ratchet portion 131 at the same time, thereby improving the locking strength between the ratchet structures.

[0039] It should be noted that, for the first ratchet portion 131 and the second ratchet portion 22 , the ratchet structure may be formed continuously around the inner wall of the tightening portion 13 or the outer wall of the nail body 10 in the circumferential direction, or may be formed discontinuously.

[0040] In one embodiment, a first limiting portion 121 is provided on the inner wall of the nail body 10 on the side of the first ratchet portion 131 close to the proximal end, and a second limiting portion 23 is provided on the outer wall of the nail head 20 on the side of the second ratchet portion 22 close to the proximal end. The first limiting portion 121 cooperates with the second limiting portion 23 to limit the extreme position of the nail head 20 moving toward the proximal end in the hollow cavity 12 of the nail body 10, thereby preventing the nail head 20 from being excessively pulled out of the cavity 12 of the nail body 10 during the pulling of the suture 30.

[0041] In one embodiment, the tail of the nail head 20 is provided with a hook portion 21, illustratively, as Figure 6 As shown, the hook portion 21 is a channel that passes through the tail of the nail head 20. After the suture 30 passes through the channel, it extends out from the inner polygon 14 at the proximal end through the cavity 12 of the nail body 10, thereby facilitating the operator to pull the suture 30.

[0042] When using the tension-adjustable anchor nail with thread in the embodiment of the present invention for bone joint and tendon suturing, a hole is pre-drilled on the bone joint, the suture 30 is passed through the channel of the nail head 20, and the suture 30 is pulled out from the distal end of the nail body 10 to the proximal end through the cavity 12. A hollow outer polygonal tool is inserted into the inner polygon 14 at the proximal end of the nail body 10, and the nail body 10 is screwed into the pre-drilled hole. The suture 30 is pulled from the hollow of the tool to the distal end, so that the nail head 20 moves proximally relative to the cavity 12 of the nail body 10 until the first spine is inserted. The tooth portion 131 and the second ratchet portion 22 stop pulling at a suitable tensioning force position, at which time the tensioning portion 13 is tensioned outward and fixed in the cancellous bone of the bone joint, and the smooth portion 132 contracts inward under the compression of the cancellous bone to avoid damaging the cancellous bone, and the end of the suture 30 is further sutured to the tendon. The entire surgical operation does not require the use of tools (the nail body 10 can also be screwed by hand), the tensioning force will not change over a long period of use, the anchor will not loosen in the cancellous bone, and excessive tensioning force will not cause damage to the cancellous bone.

[0043] The description of the embodiments herein and any reference to directions and orientations are only for the convenience of description and are not to be construed as any limitation on the scope of protection of the present invention. The description of the preferred embodiments may involve combinations of features, which may exist independently or in combination, and the present invention is not particularly limited to the preferred embodiments. The scope of the present invention is defined by the claims.

[0044] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wire anchor with adjustable tension, having an axis extending from a proximal end to a distal end, characterized in that: include: A nail body (10) is provided with a threaded portion (11) on the outside and a hollow cavity (12) formed on the inner wall; a tightening portion (13) is provided on the distal end of the nail body (10); and a first ratchet portion (131) is formed on the inner wall of the tightening portion (13); A nail head (20) is provided with a hook portion (21), and an outer wall of the nail head (20) forms a second ratchet portion (22), the second ratchet portion (22) being used to cooperate with the first ratchet portion (131), thereby allowing the nail head (20) to move toward the proximal end in the hollow cavity (12) of the nail body (10), and limiting the movement of the nail head (20) toward the distal end in the hollow cavity (12) of the nail body (10); A suture (30) connected to the nail head (20) via a hook portion (21); The mating surfaces of the first ratchet portion (131) and the second ratchet portion (22) are tapered along the axis toward the proximal end, and the first ratchet portion (131) and the second ratchet portion (22) cooperate to restrict the nail head (20) along the axis to at least two positions in the hollow cavity (12) of the nail body (10); Furthermore, the expansion portion (13) forms a smooth portion (132) between the first ratchet portion (131) and the distal end of the expansion portion (13).

2. The anchor with adjustable tension force according to claim 1, characterized in that: The expansion portion (13) of the nail body (10) is in the shape of a petal separated by a narrow groove extending along the axis.

3. The anchor with adjustable tension force according to claim 2, characterized in that: The narrow groove comprises a first narrow groove (133) and a second narrow groove (134) distributed along the circumferential direction of the outer wall of the expansion part (13), the first narrow groove (133) covers the entire expansion part (13) and the second narrow groove (134) only covers the smooth part (132).

4. The tension-adjustable wire anchor according to claim 3, characterized in that: A hole (135) is formed at one end of the first slot (133) close to the proximal end. The hole (135) penetrates the outer wall and the inner wall of the nail body (10), and the diameter of the hole (135) is greater than the width of the first slot (133).

5. The anchor with adjustable tension force according to claim 3, characterized in that: The second narrow slot (134) is expanded along the axis toward the distal end.

6. The tension-adjustable wire anchor according to claim 1, characterized in that: The first ratchet portion (131) has a plurality of ratchet structures.

7. The tension-adjustable wire anchor according to claim 1, characterized in that: The second ratchet portion (22) has at least one pair of ratchet structures.

8. The tension-adjustable wire anchor according to claim 1, characterized in that: A first limiting portion (121) is provided on the inner wall of the nail body (10) at a side of the first ratchet portion (131) close to the proximal end, and a second limiting portion (23) is provided on the outer wall of the nail head (20) at a side of the second ratchet portion (22) close to the proximal end. The first limiting portion (121) cooperates with the second limiting portion (23) to limit the extreme position of the nail head (20) moving toward the proximal end in the hollow cavity (12) of the nail body (10).

9. The tension-adjustable wire anchor according to claim 8, characterized in that: The nail head (20) is provided with a head, a middle part and a tail part, the second ratchet part (22) is arranged outside the head part, and the second limiting part (23) is formed at the transition between the middle part and the tail part.

10. The tension-adjustable wire anchor according to claim 1, characterized in that: The proximal end of the nail body (10) is provided with an inner polygon (14) for inserting a tool with a matching contour.

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