Needle clamp assembly and external bone fixator

Abstract

The present invention discloses a needle clamp assembly and an external fixator, wherein the needle clamp assembly comprises a fixing portion for accommodating a needle rod, a pressing portion for pressurizing and fixing the needle rod, and a locking portion for applying force to and locking the pressing portion, wherein a wedge-shaped conical surface is provided between the pressing portion and the fixing portion for pressurizing and locking. The external fixator comprises the needle clamp assembly. The needle clamp assembly provided by the present invention not only has low processing accuracy requirements, but also can play a stable clamping role for four or fewer needle rods, so that each needle rod can firmly fix the bone block.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, and in particular to a needle clamp assembly and an external bone fixator. Background Art

[0002] External fixators can fix fractures and correct certain bone deformities, and are an important instrument in orthopedics. There are many types of external fixators currently used in China, and the more commonly used ones are semi-ring groove external fixators, unilateral external fixators, and three-dimensional adjustable external fixators. Any external fixator includes three basic components: pins, clamps, and external connectors. Manual reduction and external fixation is to fix the two ends of the fracture in the anatomical and functional positions through the skin using the external fixator's pins, clamps, and external connectors. It fills the gap between plaster fixation and internal fixation, and has an excellent effect in fracture applications.

[0003] However, relevant studies have shown that certain complications may occur when external fixators are used. Most of these complications are related to the fixation pins, such as loosening of the pins, pin tract infection, pin breakage and fracture at the insertion site. The main causes of pin tract infection also include loosening of the pins, which makes the pin-bone interface and the pin-skin interface unstable, inflammatory reactions of the tissues around the pin tract due to periodic stress stimulation generated by limb activities, and improper handling of postoperative pin tract reactions, etc. However, observations have shown that pin tract infection can be almost completely avoided if there is no tension between the pin and the skin and the pin tract can remain stable.

[0004] It can be seen from this that the needle clamp, which is used to clamp the fixation needle and connect the external connecting rod, is an important component of the external fixator. The needle clamp components currently used are as follows: Figure 1 As shown, it includes a needle clamp body, a needle clamp block and an eccentric pin, wherein the eccentric shaft passes through the needle clamp body and the needle clamp block at the same time, and the needle clamp block is in an eccentric position. When the eccentric pin is rotated, the eccentric portion drives the four fixed needle holes on the needle clamp body to move, thereby playing the role of clamping the fixed needle. However, since the fixed needle holes are rigid, the four fixed needle holes move at the same time. If the position accuracy of one of the fixed needle holes does not meet the standard, when more than two needle rods are fixed, one needle rod will become loose, and thus a stable fixation cannot be formed. During the patient's repair process, complications such as needle tract infection may occur. Therefore, this type of needle clamp assembly has relatively high requirements on the processing accuracy or tolerance of parts. Once one part of them does not meet the standard, the needle rod cannot be well fixed, which may cause a series of complications. Summary of the invention

[0005] The object of the present invention is to overcome the defects described in the prior art, thereby providing a needle clamp assembly and an external bone fixator. The needle clamp assembly provided by the present invention not only has low processing accuracy requirements, but also can firmly clamp four or fewer needle rods, so that each needle rod can firmly fix the bone block.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A needle clamp assembly includes a fixing portion for accommodating a needle rod, a pressing portion for pressurizing and fixing the needle rod, and a locking portion for applying force to and locking the pressing portion, wherein a wedge-shaped conical surface is provided between the pressing portion and the fixing portion for pressurizing and locking.

[0008] In one embodiment, the fixing portion is provided with a accommodating groove and a needle fixing hole bypassing the accommodating groove, and the accommodating groove is provided with at least one fixing spring for fixing the needle rod in the needle fixing hole, wherein the needle fixing spring has a conical fastening surface in contact with the clamping portion, and the clamping portion is movably inserted into the accommodating groove up and down, and the clamping portion is a wedge-shaped member in linear contact with the conical fastening surface.

[0009] In one embodiment, the accommodating groove is further provided with a limiting surface, and the limiting surfaces are arranged in pairs at two ends of the fixing elastic sheet to enable the fixing elastic sheet to be loosely matched with the accommodating groove.

[0010] In one embodiment, the cross section of the accommodating groove is roughly "H"-shaped, and a needle fixing hole is bypassed at both ends of each long side of the accommodating groove, and a fixing spring is provided in the accommodating groove corresponding to each long side.

[0011] In one embodiment, the fixing spring sheet is in surface line contact with each of the needle bars.

[0012] In one embodiment, the locking portion includes a fixed shaft passing through the fixing portion and the pressing portion, and a pressure block threadedly connected to the free end of the fixing shaft. The pressure block is built into the fixing portion and drives the pressing portion to rise or fall in the accommodating groove as the fixing shaft rotates.

[0013] In one embodiment, the fixing part includes an upper fixing body and a lower fixing body that can be detachably assembled, the accommodating groove is opened on the mounting surface of the upper fixing body, the needle fixing hole is set through the upper fixing body and the lower fixing body, the lower fixing body is provided with a positioning boss, and the upper fixing body is provided with a positioning groove adapted to the positioning boss.

[0014] In one embodiment, the pressing block is loosely fitted into the lower fixing body and is coaxially arranged with the clamping portion. The fixing shaft sequentially passes through the upper fixing body, the clamping portion, the pressing block and the lower fixing body and is threadedly connected to the pressing block.

[0015] In one embodiment, the top end of the fixed shaft has a limiting protrusion and the end is provided with a limiting groove. When the fixed shaft and the pressure block raise the clamping part to the limit position, the limiting groove is located on the outside of the lower fixed body, and a retaining ring is detachably installed in the limiting groove. The retaining ring cooperates with the limiting protrusion to fasten the upper fixed body and the lower fixed body to the fixed shaft.

[0016] An external bone fixator comprises the needle clamp assembly.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The needle clamp assembly provided by the present invention is mainly composed of three parts, namely a fixing part, a pressing part and a locking part. The fixing part is used to accommodate the needle rod, the pressing part is used to pressurize and fix the needle rod, and the locking part is used to apply force to the pressing part to pressurize and fix the fixing part, and is also used to lock the pressing part on the fixing part. In the present invention, different from the prior art, a wedge-shaped conical surface is pressurized and locked between the pressing part and the fixing part, and the locking part is mainly used to lift and move the pressing part to change the relative position of the wedge and the conical surface, thereby realizing the locking or loosening of the pressing part. Compared with eccentric locking, this locking method has relatively low dimensional tolerance requirements, and the locking effect is more intuitive and stable, which greatly improves the product qualification rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic structural diagram of a needle clamp assembly provided by an embodiment of the present invention;

[0021] Figure 2 A top view of a needle clamp assembly provided by one embodiment of the present invention;

[0022] Figure 3 for Figure 2 A cross-sectional view of

[0023] Figure 4 An exploded view of a needle bar assembly provided in accordance with an embodiment of the present invention.

[0024] Description of reference numerals:

[0025] 1. Fixing part; 11. Upper fixing body; 111. Accommodating groove; 1111. Limiting surface; 112. Fixing spring piece; 1121. Conical fastening surface; 113. Positioning groove; 12. Lower fixing body; 121. Positioning boss; 13. Needle fixing hole; 2. Pressing part; 3. Locking part; 31. Fixed shaft; 311. Limiting groove; 312. Retaining ring; 313. Limiting protrusion; 32. Pressing block; 4. Needle rod. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] Example 1

[0031] See also Figure 1The present invention provides a needle clamp assembly, including a fixing portion 1 for accommodating a needle rod 4, a pressing portion 2 for pressurizing and fixing the needle rod 4, and a locking portion 3 for applying force to and locking the pressing portion 2, wherein the pressing portion 2 and the fixing portion 1 are fastened between a wedge and a conical surface.

[0032] The needle clamp assembly provided by the present invention mainly consists of three parts, namely a fixing part 1, a pressing part 2 and a locking part 3. The fixing part 1 is used to accommodate the needle rod 4, the pressing part 2 is used to pressurize and fix the needle rod 4, and the locking part 3 is used to apply force to the pressing part 2 to pressurize and fix the fixing part 1, and is also used to lock the pressing part 2 on the fixing part 1. In the present invention, different from the prior art, the pressing part 2 and the fixing part 1 of the present invention are pressurized and locked with a wedge-shaped conical surface, and the locking part 3 is mainly used to lift and move the pressing part 2 to change the relative position of the wedge and the conical surface, thereby realizing the locking or loosening of the pressing part 2. Compared with the eccentric locking, this locking method has relatively low dimensional tolerance requirements, and the locking effect is more intuitive and stable, which greatly improves the product qualification rate.

[0033] Please refer to Figure 2 The fixing portion 1 is provided with a receiving groove 111 and a needle fixing hole 13 communicating with the receiving groove 111. The receiving groove 111 is provided with at least one fixing spring 112 for fixing the needle rod 4 in the needle fixing hole 13. Figure 2 and Figure 3 The fixing spring piece 112 has a conical fastening surface in contact with the pressing part 2, and the pressing part 2 is built into the receiving groove 111 so as to be movable up and down, and the pressing part 2 is a wedge-shaped piece in line contact with the conical fastening surface 1121. That is, when the conical surface of the wedge-shaped piece presses the conical fastening surface 1121 of the fixing spring piece 112, the fixing spring piece 112 disposed in the receiving groove 111 will deform toward the needle fixing hole 13 bypassing the receiving groove 111, thereby fixing the needle rod 4 in the needle fixing hole 13, and as the locking part 3 drives the wedge-shaped piece to move up and down, a relative displacement occurs between the wedge-shaped piece and the conical fastening surface 1121, and when the bottom end of the wedge-shaped piece and the bottom end of the conical fastening surface 1121 are constantly approaching, the fastening effect between the two is constantly strengthened, and it can be foreseen that the fastening effect between the two is also more stable.

[0034] Of course, please continue to read Figure 2In order to limit the activity space of the fixed spring piece 112 and facilitate assembly, a limiting surface 1111 can also be set on the accommodating groove 111. The limiting surfaces 1111 are preferably arranged in pairs at the two ends of the fixed spring piece 112 so that the fixed spring piece 112 and the accommodating groove 111 are clearance-matched. In this way, when the clamping portion 2 presses the conical fastening surface 1121, since there is line contact between the clamping portion 2 and the conical fastening surface 1121, and there is a clearance fit between the fixed spring piece 112 and the accommodating groove 111, the fixed spring piece 112 will form a lever structure, which can stably lock the needle rod 4 arranged at any two ends of the fixed spring piece 112.

[0035] Of course, please continue to read Figure 2 , the present application can fix four needle rods 4 at the same time. At this time, the cross-section of the accommodating groove 111 can be set to be roughly "H"-shaped, and a needle fixing hole 13 is bypassed at both ends of each long side of the accommodating groove 111. A fixing spring 112 is provided in the accommodating groove 111 corresponding to each long side, and the clamping part 2 is placed in the middle of the H-shaped accommodating groove 111. Of course, the middle part of the H-shape should be appropriately widened, that is, the limiting surface 1111 can be narrowly arranged at both ends of the fixing spring 112, so as to facilitate the fixation of the clamping part 2 and the fixing spring 112, and also facilitate the flexible arrangement of the fixing spring 112 in the accommodating groove 111 to fine-tune and clamp the needle rod 4, and fix the four needle rods 4 at the same time. At this time, the clamping part 2 can use the principle of lever to press and fix the relatively arranged fixing springs 112 at the same time, and stably lock the needle rods 4 in any combination position of the four needle fixing holes 13.

[0036] Please continue reading Figure 2 In order to fix more stably, the opposite surface of the conical fastening surface 1121 on the fixing spring 112 is set to be in surface line contact with each needle rod 4. Specifically, the opposite surface can be set to an arc shape that matches the needle rod 4.

[0037] See also Figure 3 The locking portion 3 includes a fixed shaft 31 that passes through the fixing portion 1 and the pressing portion 2, and a pressure block 32 that is threadedly connected to the free end of the fixing shaft 31. The pressure block 32 is built into the fixing portion 1. The main function of the locking portion 3 is to drive the pressure block 32 to move up and down through the rotation of the fixing shaft 31. The lifting and lowering movement of the pressure block 32 can further drive the pressing portion 2 disposed above it to rise or fall in the accommodating groove 111. Since the pressing portion 2 and the fixing portion 1 are pressed and locked by a wedge-shaped conical surface, the lifting and lowering of the pressure portion 2 will be converted into lateral pressure on the fixing spring sheet 112 to achieve tightening.

[0038] Of course, when the fixing spring piece 112 is close to the extreme position of the needle fixing hole 13, a certain gap can be set between the fixing shaft 31 and the wedge-shaped piece. In this way, when tightening a single needle rod 4, it is only necessary to push the fixing spring piece 112 on one side to the extreme position first, and then lock the needle rod 4. This design enables the fixing shaft 31 to play a certain supporting role when the fixing spring piece 112 and the needle fixing hole 13 form a closed loop, thereby being able to lock the needle rod 4 more stably.

[0039] Example 2

[0040] See also Figure 4 In this embodiment, the fixing part 1 is configured as an upper fixing body 11 and a lower fixing body 12 which can be detachably assembled. The two fixing parts move separately, and there is no rigid continuity. Moreover, the clamping part 2 is a wedge-shaped structure with an appropriate slope. In this way, the processing accuracy and tolerance requirements of the parts can be appropriately reduced, which can improve the product qualification rate and the stability of the needle bar fixation.

[0041] On this basis, the accommodating groove 111 is opened on the installation surface of the upper fixed body 11 (i.e., the surface in contact with the lower fixed body 12), the needle fixing hole 13 is set through the upper fixed body 11 and the lower fixed body 12, the pressing block 32 is built into the lower fixed body 12 with clearance fit, and is coaxially arranged with the clamping part 2, and the fixed shaft 31 passes through the upper fixed body 11, the clamping part 2, the pressing block 32 and the lower fixed body 12 in sequence, and is threadedly connected with the pressing block 32. In addition, a positioning boss 121 is set on the lower fixed body 12, and a positioning groove 113 adapted to the positioning boss 121 is opened on the upper fixed body 11, which can prevent the upper fixed body 11 and the lower fixed body 12 from rotating relative to each other during assembly, and can enable the needle fixing hole 13 to be accurately matched.

[0042] In order to prevent the upper fixed body 11 and the lower fixed body 12 from detaching, in the present embodiment, a limiting protrusion 313 can be provided at the top end of the fixed shaft 31, and a limiting groove 311 can be provided at the end. When the fixed shaft 31 and the pressure block 32 raise the clamping part 2 to the limit position, the limiting groove 311 is located on the outside of the lower fixed body 12, and a retaining ring 312 is detachably installed in the limiting groove 311. The retaining ring 312 cooperates with the limiting protrusion 313 to fasten the upper fixed body 11 and the lower fixed body 12 to the fixed shaft 31.

[0043] Example 3

[0044] This embodiment provides an external fixator having the needle clamp assembly described in Embodiment 1 or Embodiment 2.

[0045] See also Figure 4When the needle clamp assembly described in Example 2 is installed, the assembly method of the needle clamp assembly of the external bone fixator is as follows: first, the two fixing springs 112 are installed in the receiving groove 111 of the upper fixing body 11, and it is noted that the conical fastening surface of the fixing spring 112 is inclined downward; then the wedge is installed in the middle of the receiving groove 111 of the upper fixing body 11, and it is noted that the cone top of the wedge is set upward; the pressing block 32 of the locking part 3 is installed in the lower fixing body 12, and it is best to set the pressing block 32 coaxially with the wedge. It can be understood that the cross-section of the pressing block 32 needs to be larger than The cross section of the wedge block is designed to increase the contact surface between the two and the force application area of ​​the pressure block 32 on the wedge block; then the upper fixed body 11 and the lower fixed body 12 which have been assembled separately are assembled together under the guidance of the positioning boss 121 and the positioning groove 113; then the fixed shaft 31 is passed through the wedge block in the upper fixed body 11 and screwed into the pressure block 32 until the other end of the lower fixed body 12 is exposed; finally, the retaining ring 312 is pressed into the limiting groove 311 of the fixed shaft 31. It can be understood that the diameter of the retaining ring 312 should be larger than the shaft hole of the lower fixed body 12.

[0046] Its working principle is: first pass the needle rod 4 through the needle fixing hole 13, and then rotate the fixing shaft 31 clockwise, at this time, the pressing block 32 moves upward, contacts with the wedge, and drives the wedge to move upward; the outer cone surface of the wedge contacts with the fixing spring piece 112, and drives the fixing spring piece 112 to move outward; the fixing spring piece 112 contacts with the needle rod 4, thereby achieving the purpose of locking the needle rod 4.

[0047] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A needle clamp assembly, characterized in that: It comprises a fixing part for accommodating the needle bar, a pressing part for pressing and fixing the needle bar, and a locking part for applying force to and locking the pressing part, wherein a wedge-shaped conical surface is provided between the pressing part and the fixing part for pressing and locking; The fixing portion is provided with a receiving groove and a needle fixing hole bypassing the receiving groove, and the receiving groove is provided with at least one fixing spring piece for fixing the needle rod in the needle fixing hole, wherein the fixing spring piece has a conical fastening surface in contact with the pressing portion, the pressing portion is built into the receiving groove so as to be movable up and down, and the pressing portion is a wedge-shaped piece in line contact with the conical fastening surface; The locking part lifts and lowers the pressing part to change the relative position of the wedge-shaped piece and the conical fastening surface, thereby locking or loosening the pressing part; Both ends of each long side of the accommodating groove are bypassed with a needle fixing hole, and each accommodating groove corresponding to the long side is provided with a fixing spring sheet; The accommodating groove is also provided with a limiting surface, and the limiting surfaces are arranged in pairs at both ends of the fixing elastic sheet, so as to make the fixing elastic sheet and the accommodating groove fit with each other in a clearance; The cross section of the accommodating groove is substantially in an "H" shape, and the accommodating groove has two long sides arranged opposite to each other.

2. The needle clamp assembly according to claim 1, characterized in that: The fixed spring sheet is in surface line contact with each of the needle bars.

3. The needle clamp assembly according to claim 1, characterized in that: The locking portion includes a fixed shaft passing through the fixing portion and the pressing portion, and a pressure block threadedly connected to the free end of the fixing shaft. The pressure block is built into the fixing portion and drives the pressing portion to rise or fall in the accommodating groove as the fixing shaft rotates.

4. The needle clamp assembly according to claim 3, characterized in that: The fixing part includes an upper fixing body and a lower fixing body that can be detachably assembled, the accommodating groove is opened on the mounting surface of the upper fixing body, the needle fixing hole is set through the upper fixing body and the lower fixing body, the lower fixing body is provided with a positioning boss, and the upper fixing body is provided with a positioning groove adapted to the positioning boss.

5. The needle clamp assembly according to claim 4, characterized in that: The pressing block is internally mounted in the lower fixing body with clearance fit and is coaxially arranged with the pressing portion. The fixing shaft sequentially passes through the upper fixing body, the pressing portion, the pressing block and the lower fixing body and is threadedly connected with the pressing block.

6. The needle clamp assembly according to claim 5, characterized in that: The top end of the fixed shaft has a limiting protrusion and the end is provided with a limiting groove. When the fixed shaft and the pressure block raise the clamping part to the limit position, the limiting groove is located on the outside of the lower fixed body, and a retaining ring is detachably installed in the limiting groove. The retaining ring cooperates with the limiting protrusion to fasten the upper fixed body and the lower fixed body to the fixed shaft.

7. An external fixator, characterized in that: A needle clamp assembly as claimed in any one of claims 1 to 6.

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