Expandable multi-head structure assembly fixed in spine

Abstract

The utility model provides an extensible multi-head structure assembly fixed in a spine, and relates to the field of medical instruments, the extensible multi-head structure assembly comprises a base body, the base body is provided with an assembling through hole and an expanding groove, the assembling through hole is used for positioning a cap structure, and the hole wall of the assembling through hole is provided with a first concave-convex part used for being clamped and matched with the cap structure. The expanding grooves are used for positioning the fixing rods. Due to the design of the structural component, the operation steps of internal fixation of the spine can be simplified, the operation difficulty can be reduced, the use flexibility can be improved, the overall structure compactness can be improved, the overall size can be reduced, the incisura can be reduced, soft tissue irritation can be reduced, and the probability of postoperative complications can be reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of medical apparatus and instruments, and particularly relates to a spine internal fixation extensible multi-head structure assembly. BACKGROUND

[0002] Pedicle screws, lamina hooks and spinal bandages are widely used in spine internal fixation surgery. On the one hand, they are connected to the anatomical structure of the spine in a mechanically stable or semi-stable manner, and on the other hand, they are connected to the rigid internal fixation rod in a stable or semi-stable manner through a cap structure, which is the general way of internal fixation of the spine. However, when the length of the internal fixation rod is not enough, or the size of the vertebral body changes, or for the purpose of enhancing the mechanical strength, or for the purpose of multi-rod fixation in a certain surgical procedure, new anchor points of the fixation rod need to be added to the original fixation structure.

[0003] The inventor found in the research that the prior art has at least the following disadvantages:

[0004] The preoperative planning ability of the operator is high, the operation is difficult, the operation is complex, the use is not flexible, the dissection occupies a large space, and the operation demand cannot be met. UTILITY MODEL CONTENT

[0005] The utility model aims to, for example, provide a spine internal fixation extensible multi-head structure assembly which can simplify the operation steps, reduce the operation difficulty, improve the use flexibility, improve the overall structure compactness, reduce the overall volume, reduce the incision, reduce the irritation of soft tissue, and reduce the incidence of postoperative complications.

[0006] The embodiments of the utility model can be implemented as follows:

[0007] In a first aspect, the utility model provides a spine internal fixation extensible multi-head structure assembly, which comprises:

[0008] A base body is provided with an assembly through hole and an expansion groove, the assembly through hole is used for positioning a cap structure, a first concave-convex part used for clamping cooperation with the cap structure is arranged on the hole wall of the assembly through hole, and the expansion groove is used for positioning a fixation rod.

[0009] In an optional embodiment, the number of expansion grooves is set to be multiple.

[0010] Based on the above scheme, each expansion groove can fix one fixation rod, and by reasonably designing the number of expansion grooves, multiple fixation rods can be positioned, the use is flexible, and the use range is wide.

[0011] In an optional embodiment, multiple expansion grooves are distributed on the same side of the assembly through hole or on the opposite sides of the assembly through hole.

[0012] Based on the above scheme, the distribution mode of the expansion groove is different, and the fixing rod can be distributed on the two sides or the same side of the assembly hole. The use is flexible, the use range is wide, and different scene requirements can be adapted.

[0013] In an optional embodiment, a positioning groove for clamping cooperation with the fixing rod is arranged on the hole wall of the assembly hole, and the positioning groove has a spacing with the first concave-convex part in the circumferential direction of the assembly hole.

[0014] Based on the above scheme, after the cap structure is installed in the assembly hole, the clamping groove on the cap structure for clamping the fixing rod is in communication with the positioning groove, and the fixing rod can be clamped in the clamping groove and the positioning groove at the same time. The position of the fixing rod is firm and reliable.

[0015] In an optional embodiment, the slot of the positioning groove and the slot of the expansion groove are located on the same side of the base body.

[0016] Based on the above scheme, the cap structure is put into the assembly hole from one port of the assembly hole, and the slot of the clamping groove formed by the cap structure and the slot of the positioning groove are located on the same side. The fixing rod can be directly put into the positioning groove from the slot of the clamping groove, and the installation and positioning of the fixing rod are facilitated.

[0017] In an optional embodiment, the slot of the positioning groove and the slot of the expansion groove are located on opposite sides of the base body.

[0018] Based on the above scheme, the cap structure is put into the assembly hole from one port of the assembly hole, and the slot of the clamping groove formed by the cap structure and the slot of the positioning groove are located on opposite sides of the base body. The fixing rod is inserted into the insertion hole formed by cooperation of the clamping groove and the positioning groove for assembly, and the height of the cap structure extending from the base body on the side corresponding to the slot of the expansion groove is reduced.

[0019] In an optional embodiment, the assembly hole has a first wall and a second wall connected and arranged at an included angle, the first concave-convex part is arranged on the first wall, and the positioning groove is arranged on the second wall.

[0020] Based on the above scheme, the clamping groove of the cap structure is in butt joint communication with the positioning groove, the clamping arm of the cap structure can adaptively move in the slot width direction of the clamping groove, when the cap structure is installed, the second concave-convex part corresponding to the first concave-convex part is arranged on the clamping arm, when the second concave-convex part contacts with the first concave-convex part, the clamping arm can be inwardly close, so that the second concave-convex part and the first concave-convex part are prevented from interfering, and installation is facilitated. When the second concave-convex part moves to be completely clamped with the first concave-convex part, the clamping arm is expanded outwardly, the second concave-convex part and the first concave-convex part are tightly clamped, and assembly is facilitated. Meanwhile, when the cap structure is installed, the fixing screw is arranged in the clamping groove to lock the fixing rod, under the action of the fixing screw, the clamping arm can be properly expanded outwardly, and the firmness of the combination of the second concave-convex part and the first concave-convex part is improved.

[0021] In an optional implementation, the first concave-convex part is arranged as a protrusion, and a guide inclined surface is arranged on the surface of the protrusion away from the hole wall of the assembly through hole.

[0022] Based on the above scheme, the first concave-convex part has a simple structure, is convenient to process, and the guide inclined surface is arranged, so that the assembly of the cap structure and the base body is facilitated.

[0023] In an optional implementation, the number of the first concave-convex parts is multiple and the first concave-convex parts are arranged at intervals in the circumferential direction of the assembly through hole.

[0024] Based on the above scheme, the multiple first concave-convex parts cooperate with the cap structure, and the firmness can be improved.

[0025] In an optional implementation, the two opposite groove side walls of the expansion groove are both provided with a threaded groove.

[0026] Based on the above scheme, the fixing screw is screwed with the threaded groove, and the fixing rod can be pressed in the expansion groove.

[0027] The beneficial effects of the embodiments of the utility model include, for example:

[0028] In summary, the spinal internal fixation expandable multi-head structure assembly provided by the embodiment can place a cap structure in the assembly through hole, can place a fixing rod in the cap structure, and can set a fixing screw in the clamping groove of the cap structure, and the fixing rod is fixed in the clamping groove through the fixing screw. Meanwhile, a fixing rod can be placed in the expansion groove, and the fixing rod can be fixed through the fixing screw connected with the expansion groove. Moreover, the number of expansion grooves can be set as required, so that two or more than two fixing rods can be fixed, the number of fixing rods is expanded, different surgical scenes are adapted, use is flexible, and the use range is wide. When the cap structure is matched with the assembly through hole, the second concave-convex part on the cap structure can be clamped and matched with the first concave-convex part on the hole wall of the assembly through hole, the cap structure and the base body are limited in the axial direction, that is, the first concave-convex part and the second concave-convex part form a mortise and tenon clamping structure, the cap structure is fixedly connected with the base body, the freedom of the cap structure in the axial direction of the assembly through hole is limited, and the cap structure cannot come out of the assembly through hole, so that the position of the fixing rod on the cap structure is firm and reliable. The mortise and tenon clamping structure is located in the assembly through hole and does not occupy external space, so that the volume of the overall structure is not increased, meanwhile, a stud for fixing the cap structure and protruding from the slot of the clamping groove of the cap structure does not need to be arranged in the clamping groove of the cap structure, and a nut screwed on the stud outside is also saved, so that the structure is simplified, the height of the overall structure in the axial direction of the assembly through hole is reduced, the notch is effectively reduced, the irritation of soft tissue is less, and the incidence of postoperative pain and discomfort caused by internal fixation surgery is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0030] Figure 1 FIG. 1 is a schematic view of a spinal internal fixation expandable multi-head structure assembly according to an embodiment of the present application;

[0031] Figure 2 FIG. 2 is a sectional view of the spinal internal fixation expandable multi-head structure assembly according to the embodiment of the present application; Figure 1

[0032] Figure 3 FIG. 3 is a schematic view of a deformation of the spinal internal fixation expandable multi-head structure assembly according to the embodiment of the present application;

[0033] Figure 4 FIG. 4 is a sectional view of the deformation of the spinal internal fixation expandable multi-head structure assembly according to the embodiment of the present application; Figure 3

[0034] Figure 5 ​​A first application schematic view of the expandable multi-head structure assembly for internal fixation of the spinal column of the embodiment of the present application;

[0035] Figure 6 A cross-sectional view corresponding to Figure 5 ;

[0036] Figure 7 A second application schematic view of the expandable multi-head structure assembly for internal fixation of the spinal column of the embodiment of the present application;

[0037] Figure 8 A third application schematic view of the expandable multi-head structure assembly for internal fixation of the spinal column of the embodiment of the present application;

[0038] Figure 9 A cross-sectional view corresponding to Figure 8 ;

[0039] Figure 10 A fourth application schematic view of the expandable multi-head structure assembly for internal fixation of the spinal column of the embodiment of the present application;

[0040] Figure 11 A cross-sectional view corresponding to Figure 10 .

[0041] Icon:

[0042] 100-base; 110-assembly through hole; 111-first side wall; 112-second side wall; 113-third side wall; 114-fourth side wall; 115-first port; 116-second port; 120-expansion groove; 121-second threaded groove; 130-first convex-concave part; 131-guiding slope; 140-positioning groove; 200-cap structure; 210-bottom plate; 211-fixing through hole; 220-clamping arm; 230-clamping groove; 231-first threaded groove; 240-second convex-concave part; 300-fixing piece; 400-pressing block; 500-fixing rod; 600-first fixing screw; 700-second fixing screw. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0044] Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the application.

[0045] It should be noted that similar reference numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0046] In the description of the application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship of the product in use, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0047] In addition, if the terms "first", "second" and the like appear, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0048] It should be noted that the features in the embodiments of the application can be combined with each other without conflict.

[0049] Embodiments

[0050] Please refer to Figures 1-4 In this embodiment, the expandable multi-head structure assembly for internal fixation of the spine includes a base body 100, the base body 100 is provided with an assembly through hole 110 and an expansion groove 120, the assembly through hole 110 is used for positioning a cap structure 200, and a first concave-convex part 130 for clamping cooperation with the cap structure 200 is arranged on the hole wall of the assembly through hole 110. The expansion groove 120 is used for positioning a fixing rod 500.

[0051] Please refer to Figures 5-11 It should be noted that the expandable multi-head structure assembly for internal fixation of the spine provided in this embodiment can be used in cooperation with the cap structure 200, the fixing member 300, the pressing block 400, the fixing rod 500, the first fixing screw 600 and the second fixing screw 700.

[0052] Please refer to Figure 5 and Figure 6The cap structure 200 includes a bottom plate 210 and two clamping arms 220 in an integrated design, the two clamping arms 220 are located on opposite sides of the bottom plate 210, and the bottom plate 210 and the two clamping arms 220 cooperatively define a clamping groove 230, the inner side of the clamping arm 220 is a groove side wall of the clamping groove 230, and the inner wall surface of each clamping arm 220 is provided with a first threaded groove 231, and the first threaded grooves 231 on the two clamping arms 220 are capable of being screwed with a first fixing screw 600. The bottom plate 210 is provided with a fixing through hole 211, which can also be understood as being provided through the groove bottom wall of the clamping groove 230. The fixing member 300 can be a lamina hook or a pedicle screw, and in this embodiment, the fixing member 300 is taken as a pedicle screw for example. The pressing block 400 is installed in the clamping groove 230, and the pressing block 400 cooperates with the spherical head of the pedicle screw, so that the angle of the pedicle screw can be adjusted by 360° before the pedicle screw is locked. The fixing rod 500 is placed in the clamping groove 230 and above the pressing block 400, the first fixing screw 600 cooperates with the first threaded grooves 231 on the two clamping arms 220, and is screwed in the clamping groove 230, and the first fixing screw 600 is used to lock the fixing rod 500, the pressing block 400 and the pedicle screw.

[0053] Meanwhile, the outer side surface of at least one of the two clamping arms 220 of the cap structure 200 is provided with a second concave-convex part 240, which can be connected with the first concave-convex part 130 on the hole wall of the assembly through hole 110 to form a mortise and tenon connection structure.

[0054] As described above, the use mode of the spinal internal fixation expandable multi-head structure assembly provided in the embodiment includes, for example:

[0055] Please refer to Figures 8-11 The cap structure 200 is inserted into the assembly through hole 110 with the bottom plate 210 as the front end, the pedicle screw is inserted into the fixing through hole 211, the pressing block 400 is installed in the clamping groove 230, and one fixing rod 500 is placed in the clamping groove 230 and abuts against the pressing block 400. After the angle of the pedicle screw is adjusted, the first fixing screw 600 is screwed in the clamping groove 230, and the first fixing screw 600 is used to lock the fixing rod 500, the pressing block 400 and the pedicle screw. At this time, the fixation of one fixing rod 500 is completed. Meanwhile, one fixing rod 500 can be placed in the expansion groove 120, and the fixing rod 500 can be fixed by the second fixing screw 700 connected with the expansion groove 120. It should be understood that the number of expansion grooves 120 on the base body 100 can be set as required, so as to be capable of fixing two and more than two fixing rods 500, realize the expansion of the number of fixing rods 500, adapt to different surgical scenes, be flexible to use, and have a wide range of use.

[0056] When the cap structure 200 is matched with the assembly through hole 110, the second concave-convex part 240 on the clamping arm 220 can be clamped and matched with the first concave-convex part 130 on the hole wall of the assembly through hole 110, realizing the limiting of the cap structure 200 and the base body 100 in the axial direction of the assembly through hole 110, that is, the first concave-convex part 130 and the second concave-convex part 240 cooperate to form a mortise and tenon clamping structure, realizing the fixed connection of the cap structure 200 and the base body 100, so that the freedom of the cap structure 200 in the axial direction of the assembly through hole 110 is limited, and the cap structure 200 cannot be taken out of the assembly through hole 110, thereby ensuring the firm and reliable position of the fixed rod 500 on the cap structure 200. The mortise and tenon clamping structure is located in the assembly through hole 110 and does not occupy external space, which does not increase the volume of the overall structure, at the same time, a threaded hole for fixing the cap structure 200 and extending out of the notch of the clamping groove 230 of the cap structure 200 is not arranged in the clamping groove 230 of the cap structure 200, and a nut screwed on the threaded hole outside is also omitted, thereby simplifying the structure, reducing the height of the overall structure in the axial direction of the assembly through hole 110, effectively reducing the notch, and the incidence of postoperative pain and discomfort caused by internal fixation surgery is reduced.

[0057] The following embodiments illustrate the details of the expandable multi-head structure assembly for internal fixation of the spine provided in the present application by way of example.

[0058] Please refer to Figure 5 , Figure 8 and Figure 10 , it should be understood that the number of the expansion groove 120 on the base body 100 can be one or more, and the number of the expansion groove 120 is consistent with the number of the expansion fixed rod 500, that is, one fixed rod 500 can be positioned in each expansion groove 120, and multiple expansion grooves 120 can fix multiple fixed rods 500, which is flexible in use according to the needs.

[0059] In addition, when the number of the expansion groove 120 is multiple, that is, the number of the expansion groove 120 is two or more, the multiple expansion grooves 120 can be located on the same side of the assembly through hole 110, or the multiple expansion grooves 120 can be distributed on the opposite sides of the assembly through hole 110.

[0060] In order to realize the fixation of the fixed rod 500 in the expansion groove 120, a second threaded groove 121 can be arranged on the groove side wall of the expansion groove 120, and the second fixed screw 700 is screwed with the second threaded groove 121 to press the fixed rod 500 tightly in the expansion groove 120, which is simple and reliable in installation and convenient in operation.

[0061] Please refer to Figure 1 and Figure 2In the embodiment, optionally, the assembly through hole 110 has a first port 115 and a second port 116 opposite in the axial direction of the assembly through hole 110, the first port 115 is located on the same side as the slot of the expansion groove 120, the cap structure 200 is put into the assembly through hole 110 from the first port 115, the first convex-concave part 130 and the second convex-concave part 240 are clamped and matched, and the cap structure 200 is prevented from being pulled out from the second port 116. Meanwhile, the assembly through hole 110 has a first side wall 111 and a second side wall 112 arranged in a first direction, and a third side wall 113 and a fourth side wall 114 arranged in a second direction, the first direction and the second direction are perpendicular. The first side wall 111, the third side wall 113, the second side wall 112 and the fourth side wall 114 are sequentially connected end to end. The assembly through hole 110 and the expansion groove 120 are arranged in the first direction. The first side wall 111 is provided with the first convex-concave part 130, the first convex-concave part 130 can be a protrusion, and a guide inclined surface 131 can be arranged on the surface of the first convex-concave part 130 away from the first side wall 111, the guide inclined surface 131 is used for contacting the clamping arm 220 when the cap structure 200 is pulled out of the assembly through hole 110 from the first port 115 to the second port 116, so that the two clamping arms 220 have a tendency to approach, so that the first convex-concave part 130 and the second convex-concave part 240 are smoothly separated, and the disassembly is facilitated.

[0062] It should be understood that in other embodiments, the first convex-concave part 130 can also be arranged on the second side wall 112, or the number of the first convex-concave parts 130 on the first side wall 111 and the second side wall 112 can be two or more. In this way, by arranging a plurality of first convex-concave parts 130, and a plurality of second convex-concave parts 240 are arranged on the clamping arms 220 of the cap structure 200 corresponding to the plurality of first convex-concave parts 130 arranged in the circumferential direction of the assembly through hole 110, the plurality of first convex-concave parts 130 and the plurality of second convex-concave parts 240 are clamped and matched, a plurality of riveting clamping structures can be formed, and the combination firmness is improved.

[0063] Please refer to Figure 1 or Figure 3Meanwhile, the positioning grooves 140 are arranged on the third sidewall 113 and the fourth sidewall 114, and the two positioning grooves 140 are symmetrically arranged, and the fixing rod 500 passes through the two positioning grooves 140 at the same time. That is to say, when the cap structure 200 is inserted into the assembly through hole 110, the two positioning grooves 140 are respectively communicated with the two sides of the clamping groove 230, and the fixing rod 500 can pass through the clamping groove 230 and the two positioning grooves 140 at the same time, so as to realize installation positioning. When the cap structure 200 is matched with the assembly through hole 110, the width direction of the clamping groove 230 is the first direction, the two clamping arms 220 are arranged in the first direction, and the two clamping arms 220 are respectively in contact with the first sidewall 111 and the second sidewall 112, so as to limit the outward expansion of the clamping arm 220 through the first sidewall 111 and the second sidewall 112. When the first fixing screw 600 is screwed in the clamping groove 230, the first fixing screw 600 is tightly matched with the clamping groove 230, and the first fixing screw 600 will not be loosened, so that the fixing effect is good. Meanwhile, since the first concave-convex part 130 is arranged on the first sidewall 111 or the second sidewall 112, after the second concave-convex part 240 on the clamping arm 220 is clamped and matched with the first concave-convex part 130, under the action of the first fixing screw 600, the two clamping arms 220 can be tightly attached to the first sidewall 111 and the second sidewall 112, so that the clamping of the first concave-convex part 130 and the second concave-convex part 240 is more firm, and the cap structure 200 will not be pulled out of the assembly through hole 110. Through the first fixing screw 600, the positioning of the fixing rod 500 is realized, and the firmness of the matching of the cap structure 200 and the base body 100 is improved.

[0064] Please combine Figure 1 and Figure 2 In an embodiment, optionally, the slots of the positioning grooves 140 and the slots of the expansion grooves 120 are located on opposite sides of the base body 100. The cap structure 200 is put into the assembly through hole 110 from the first port 115 of the assembly through hole 110, the slots of the clamping groove 230 formed by the cap structure 200 and the slots of the positioning grooves 140 are located on opposite sides of the base body 100, the fixing rod 500 is assembled by being inserted into the insertion hole formed by the clamping groove 230 and the positioning grooves 140, and the height of the cap structure 200 extending from the side of the base body 100 corresponding to the slot of the expansion groove 120 is reduced, and then the overall structure height is reduced.

[0065] Please combine Figure 3 and Figure 4In another embodiment, the notch of the positioning groove 140 and the notch of the expanding groove 120 are located on the same side of the base body 100, the cap structure 200 is put into the assembly through hole 110 from the first port 115 of the assembly through hole 110, the notch of the clamping groove 230 formed by the cap structure 200 is located on the same side of the notch of the positioning groove 140, and the fixing rod 500 can be directly put into the positioning groove 140 from the notch of the clamping groove 230, so that the installation and positioning of the fixing rod 500 are facilitated.

[0066] In addition, the first concave-convex part 130 can be provided as a protrusion, and the second concave-convex part 240 can be provided as a groove matched with the protrusion. Obviously, in other embodiments, the first concave-convex part 130 can also be a groove, and correspondingly, the second concave-convex part 240 is provided as a protrusion matched with the groove, etc.

[0067] The spinal internal fixation expandable multi-head structure assembly provided in the embodiment is connected and fixed by the internal hidden mortise and tenon joint structure, does not occupy the external space of the base body 100, does not increase the volume of the overall structure, at the same time, does not need to be provided with a stud for fixing the cap structure 200 and extending out of the notch of the clamping groove 230 in the clamping groove 230 of the cap structure 200, and also saves a nut screwed on the stud, simplifies the structure, reduces the height of the overall structure in the axial direction of the assembly through hole 110, effectively reduces the notch, and causes less irritation of soft tissues, so that the incidence of postoperative pain and discomfort caused by internal fixation surgery is reduced.

[0068] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A spinal internal fixation expandable multi-head structure assembly, characterized in that, The application relates to a spinal internal fixation expandable multi-head structure assembly, comprising: a base body (100) provided with an assembly through hole (110) and an expansion groove (120), the assembly through hole (110) is used for positioning a cap structure (200), and a first concave-convex part (130) used for clamping connection with the cap structure (200) is arranged on the hole wall of the assembly through hole (110); the expansion groove (120) is used for positioning a fixing rod (500).

2. The spinal internal fixation expandable multi-head structure assembly according to claim 1, wherein: a plurality of the expansion grooves (120) are arranged.

3. The spinal internal fixation expandable multi-head structure assembly according to claim 2, wherein: the plurality of the expansion grooves (120) are arranged on the same side of the assembly through hole (110) or on opposite sides of the assembly through hole (110).

4. The spinal internal fixation expandable multi-head structure assembly according to claim 1, wherein: a positioning groove (140) used for clamping connection with the fixing rod (500) is arranged on the hole wall of the assembly through hole (110), and the positioning groove (140) and the first concave-convex part (130) are spaced apart in the circumferential direction of the assembly through hole (110).

5. The spinal internal fixation expandable multi-head structure assembly according to claim 4, wherein: the slot of the positioning groove (140) and the slot of the expansion groove (120) are arranged on the same side of the base body (100).

6. The spinal internal fixation expandable multi-head structure assembly according to claim 4, wherein: the slot of the positioning groove (140) and the slot of the expansion groove (120) are arranged on opposite sides of the base body (100).

7. The spinal internal fixation expandable multi-head structure assembly according to claim 4, wherein: the assembly through hole (110) has a first wall and a second wall connected and arranged at an angle, the first concave-convex part (130) is arranged on the first wall, and the positioning groove (140) is arranged on the second wall.

8. The spinal internal fixation expandable multi-head structure assembly according to claim 1, wherein: the first concave-convex part (130) is arranged as a protrusion, and a guide inclined surface (131) is arranged on the surface of the protrusion away from the hole wall of the assembly through hole (110).

9. The spinal internal fixation expandable multi-head structure assembly according to claim 1, wherein: a plurality of the first concave-convex parts (130) are arranged at intervals in the circumferential direction of the assembly through hole (110).

10. The spinal internal fixation expandable multi-head structure assembly according to claim 1, wherein: thread grooves are arranged on the two groove side walls of the expansion groove (120).

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