CN217366054U - Multi-anchor screw unit and multi-anchor screw assembly for fixing lumbar vertebra and sacrum - Google Patents

Abstract

A multi-anchor screw unit (100) for lumbar and sacral fixation comprises a main screw (10), a screw seat (20), a connecting piece tail cap (30), an auxiliary screw (40) and an auxiliary screw tail cap (50). The main nail comprises a main nail body (12) and a main nail tail (14). The screw base comprises a main screw fixing part (22), a main screw tail cap (24) and an auxiliary screw fixing part (26). The secondary staple includes a secondary staple body (42) and a secondary staple tail (44). The height of vice nail fixed part is less than main nail fixed part, and vice nail is rotationally worn to locate vice nail fixed part, and vice nail tail is polyhedral structure or surperficial coarse, and is fixed through the female connection of vice nail tail cap and vice nail fixed part. The utility model discloses still provide the multi-anchor screw subassembly that is used for lumbar vertebrae and sacrum to fix, including multi-anchor screw unit. Through main nail and the mutual support of vice nail, the interlock intensity of many anchor point screw unit and sclerotin is high, reduces the fixed not hard up risk of postoperative, avoids destroying the sacroiliac joint.

Description

Multi-anchor screw unit and multi-anchor screw assembly for lumbar and sacral fixation

technical field

The utility model patent relates to a medical instrument suitable for spinal surgery, especially a multi-anchor point screw unit used for lumbar spine and sacrum fixation, and a multi-anchor point screw assembly using the multi-anchor point screw unit.

Background technique

Currently, internal fixation used for lumbosacral spine surgery mainly includes pedicle screws, cortical bone screws and sacroiliac screws. FIG. 8 shows a single anchor point screw unit 80 commonly used for lumbar spine and sacral fixation. It includes a fixing seat 81 , a screw 82 , a screw cap 83 and a tail cap 84 . The screw 82 is limited by the screw cap 83 to the fixing seat 81 . , can be rotated arbitrarily to suit the orientation and position during surgery. A hole 85 is opened in the fixation seat 81, and in spinal surgery, a connecting rod (not shown in the figure) passes through the hole 85 to connect multiple sets of screw units, so as to realize the internal fixation of the lumbosacral spine.

The screw tail of the screw 82 is a ball socket, and the end of the screw 82 away from the main body of the screw is provided with an inner hexagon, and the screw is inserted into the bone by applying force at the inner hexagon. The screw cap 83 defines the tail of the screw 82 in the screw hole of the fixing base 81, so that the screw 82 can be rotated 360°. When a plurality of single-anchor point screw units 80 are connected by a connector, the tail cap 84 locks the connector, thereby connecting the plurality of single-anchor point screw units in series to form a complete fixation structure to achieve internal fixation of the lumbosacral spine.

However, pedicle screws, cortical bone screws, and sacroiliac screws all have some technical deficiencies. The fixation strength of pedicle screws is limited. It is a single anchor point screw fixation with a single direction. It only relies on the occlusal fixation between the screw and the cancellous bone or cortical bone. In the long-segment fixation operation of the spine, screw loosening, pull-out and false joint formation often occur. Cortical bone screws are also fixed with a single anchor point screw with a single direction, and only rely on the occlusal fixation between the screw and the cortical bone; while the sacroiliac screws with higher fixation strength (such as S2AI screws) often require a larger surgical scope. , and the screw will destroy the patient's sacroiliac joint, affecting the patient's life function.

Utility model content

The purpose of the utility model is to provide a multi-anchor point screw unit for lumbar and sacrum fixation, which has higher occlusal strength, reduces the risk of post-operative fixation loosening, and avoids damage to the sacroiliac joint.

Another object of the present invention is to provide a multi-anchor screw assembly for lumbar spine and sacrum fixation.

The utility model provides a multi-anchor point screw unit for lumbar vertebra and sacrum fixation, which comprises a main screw, a screw seat, a connecting piece tail cap, an auxiliary screw and an auxiliary screw tail cap. The main nail includes a main nail body and a main nail tail fixedly connected with the main nail body. The screw seat includes a main nail fixing part, a main nail tail cap and an auxiliary nail fixing part. The main nail fixing part is provided with a main nail hole and a connecting piece groove, and the inner wall of the connecting piece groove is provided with an internal thread; the main nail tail cap rotatably defines and fixes the main nail tail in the main nail hole. The end cap of the connector is provided with an external thread matched with the internal thread of the groove of the connector. The auxiliary nail includes a fixedly connected auxiliary nail body and an auxiliary nail tail. The auxiliary nail tail cap is provided with an external thread. The height of the auxiliary nail fixing part is lower than that of the main nail fixing part, and the bottom of the auxiliary nail is provided with a through auxiliary nail hole, the inner wall of the auxiliary nail is provided with an inner thread matched with the outer thread of the auxiliary nail tail cap, and the auxiliary nail body is detachably passed through. In the auxiliary nail hole, the auxiliary nail tail is rotatably arranged in the auxiliary nail hole and fixed by the auxiliary nail tail cap.

Through the coordinated fixation of the main screw and the auxiliary screw, the two screws support each other and have the structural strength that the single anchor point screw does not have. It also avoids damage to the sacroiliac joint and adversely affects the quality of life of patients after surgery.

In yet another exemplary embodiment of the multi-anchor point screw unit for lumbar and sacral fixation, the surface of the tail of the auxiliary screw is in a polyhedron shape or a rough surface, which can increase the resistance of the tail of the auxiliary screw during fixation. The auxiliary nail is stably fixed to the auxiliary nail fixing part.

The utility model also provides a multi-anchor point screw assembly for lumbar vertebra and sacrum fixation, including the above-mentioned multi-anchor point screw unit and connector for lumbar vertebra and sacrum fixation. The connecting piece can pass through the connecting piece groove of the main nail fixing part, and the connecting piece is connected with the multi-anchor point screw unit through the fitting of the connecting piece tail cap and the thread on the connecting piece groove. Through the connection between the connector and the multi-anchor point screw unit, the supporting and fixing function of the multi-anchor point screw unit to the entire screw fixing structure is fully exerted.

In yet another exemplary embodiment of the multi-anchor screw assembly for lumbar spine and sacral fixation, the connecting member is a connecting rod.

Compared with the existing single-anchor point screw unit, the stability of the screw is maintained only by the occlusion with the bone, while the multi-anchor point screw of the present invention increases the occlusion point and the occlusal area with the bone, and improves the stability. The two screws support each other and have higher structural strength than a single anchor point screw unit, reducing the risk of postoperative internal fixation loosening. At the same time, it also avoids excessive surgical exposure and sacroiliac joint damage, achieves stable fixation, avoids excessive increase of the impact on the patient, and improves the surgical effect and the patient's quality of life.

Description of drawings

The following drawings merely illustrate and explain the present invention schematically, and do not limit the scope of the present invention.

FIG. 1 is a perspective exploded schematic view of a multi-anchor point screw unit used for lumbar spine and sacrum fixation according to the present invention.

FIG. 2 is a schematic structural diagram of the screw seat of the multi-anchor point screw unit shown in FIG. 1 .

FIG. 3 is a schematic cross-sectional view of the assembled screw base shown in FIG. 2 .

FIG. 4 is a schematic cross-sectional view of the multi-anchor point screw unit shown in FIG. 1 after assembly.

Figure 5 is a schematic illustration of a multi-anchor screw assembly for lumbar and sacral fixation.

Fig. 6 is a schematic diagram of the use state of using the multi-anchor point screw assembly shown in Fig. 5 for unilateral lumbar spine fixation.

Fig. 7 is a schematic diagram of the use state of using the multi-anchor point screw assembly shown in Fig. 5 for bilateral sacrum fixation.

FIG. 8 is a schematic cross-sectional view of a conventional single-anchor point screw unit for lumbar spine and sacral fixation.

Label description

10 main nails

12 Main nail body

14 main nail tail

20 Screw holder

22 Main nail fixing part

222 Main nail hole

224 Connector groove

24 main nail tail cap

26 pairs of nail fixing parts

262 pairs of nail holes

30 Connector end cap

40 pairs of nails

42 pairs of nail bodies

44 pairs of nail tail

50 pairs of nail tail caps

80 Single Anchor Screw Unit

81 Mounts

82 screws

83 screw cap

84 tail cap

85 holes

100 screw unit

200 connectors.

Detailed ways

In order to have a clearer understanding of the technical features, purposes and effects of the utility model, the specific embodiments of the present utility model will now be described with reference to the accompanying drawings, in which the same reference numerals represent the same parts.

As used herein, "schematic" means "serving as an example, instance, or illustration" and any illustration, embodiment described herein as "schematic" should not be construed as a preferred or advantageous one Technical solutions.

FIG. 1 is a perspective exploded schematic view of a multi-anchor point screw unit for lumbar spine and sacral fixation. The multi-anchor point screw unit 100 includes a main screw 10 , a screw base 20 , a connector tail cap 30 , an auxiliary screw 40 and an auxiliary screw tail cap 50 .

The main nail 10 includes a main nail body 12 and a main nail tail 14 that are fixedly connected. The screw base 20 includes a main nail fixing part 22 , a main nail tail cap 24 and an auxiliary nail fixing part 26 . Internal threads are provided on the inner wall of the main nail fixing portion 22 . The height of the auxiliary nail fixing part 26 is lower than that of the main nail fixing part 22 , and the inner wall thereof is provided with internal threads. The main tail cap 24 defines and secures the main tail 14 (see FIG. 4 ).

The connector tail cap 30 is provided with an external thread matched with the internal thread of the main nail fixing portion 22 .

The auxiliary nail 40 includes a fixedly connected auxiliary nail body 42 and an auxiliary nail tail 44 .

The auxiliary nail tail cap 50 is provided with an external thread matched with the internal thread of the auxiliary nail fixing portion 26 .

Through the coordinated fixation of the main screw 10 and the auxiliary screw 40, the two screws support each other and have higher structural strength than a single screw. The risk of loosening also avoids damage to the sacroiliac joint and adversely affects the quality of life of patients after surgery.

FIG. 2 is a schematic structural diagram of the screw seat of the multi-anchor point screw unit shown in FIG. 1 . As shown in FIG. 2 , the screw base 20 includes a main nail fixing part 22 , a main nail tail cap 24 and an auxiliary nail fixing part 26 .

FIG. 3 is a schematic cross-sectional view of the screw base 20 of the multi-anchor point screw unit. As shown in FIG. 3 , the main nail fixing portion 22 is provided with a main nail hole 222 and a connector groove 224 . The main nail hole 222 is a vertical through hole, the connector groove 224 is opened on the upper part of the main nail fixing part 22 and is a front and rear through hole. The inner wall of the connector groove 224 is provided with an internal thread. The height of the auxiliary nail fixing part 26 is lower than that of the main nail fixing part 22 , and the bottom of the auxiliary nail fixing part 26 has a through auxiliary nail hole 262 .

FIG. 4 is a schematic cross-sectional view of the multi-anchor point screw unit shown in FIG. 1 after assembly. The main nail 10 is rotatably passed through the main nail hole, and the main nail tail 14 is restricted in the main nail hole by the main nail tail cap 24, so that the main nail 10 and the main nail fixing part are integrated into a structure, and the main nail 10 is in the main nail hole. Any rotation in the nail hole. The connecting piece groove 224 is formed on the upper part of the main nail fixing part, and is located above the main nail tail cap 24 . The central portion of the main nail tail cap 24 has an arc-shaped depression, which has the same arc and depth as the connector groove 224 , so as to facilitate receiving, for example, a connector and prevent it from shaking in the connector groove 224 . The auxiliary nail 40 can rotate freely in the auxiliary nail hole through the spherical auxiliary nail tail 44 . The screw seat 20 is provided with a main screw hole and an auxiliary screw hole to fix the main screw 10 and the auxiliary screw 40 respectively. The two screws support each other to improve the occlusal strength and reduce the risk of internal fixation loosening after surgery.

In an exemplary embodiment of the present invention, the surface of the auxiliary nail tail 44 is in the shape of a polyhedron (such as a football shape), or a rough surface, which can increase the resistance when it is fixed with the auxiliary nail tail cap 50, so that the The auxiliary nail 40 is stably fixed to the auxiliary nail fixing portion 26 .

Figure 5 is a schematic illustration of a multi-anchor screw assembly for lumbar and sacral fixation. The multi-anchor point screw assembly includes a multi-anchor point screw unit 100 and a connector 200 . The connector 200 can pass through the connector groove 224 of the main nail fixing part 22 , and the connector 200 is connected to the multi-anchor point screw unit 100 through the thread fit of the connector end cap 30 and the connector groove 224 . Before the operation, according to the CT reconstruction parameters of the patient's lumbar spine or sacrum, determine the insertion angle and length of the main screw 10 and the auxiliary screw 40, and determine the specifications of the screw seat, the main screw and the auxiliary screw. During the operation, the main nail 10 is first placed, the position of the main nail tail 14 is adjusted, the auxiliary nail 40 is inserted according to the angle planned before the operation, and then the auxiliary nail tail cap 50 is locked to fix the angle of the auxiliary nail 40 . Then, the connector 200 is placed, connected with the multi-anchor screw unit 100, and finally the end cap 30 of the connector is locked.

When using a multi-anchor screw assembly, the main or secondary screw of the multi-anchor screw unit can be placed using eg a cortical bone track or a pedicle screw track, and the other screw (secondary or primary screw) using eg a sacral wing track. Since the CT value (an indicator of anti-pullout strength) of the sacral pterygium screw is higher than that of the pedicle screw, the placement of the two screws increases the occlusal area with the bone, and the bone density at the screw placement is higher than that of the traditional vertebral arch. The cancellous bone where the root nail is placed can effectively improve the occlusal strength.

Fig. 6 is a schematic diagram of a use state of the multi-anchor point screw assembly for unilateral lumbar vertebra fixation. As shown in FIG. 6 , a multi-anchor point screw unit 100 is placed in the patient's sacrum, a multi-anchor point screw unit 100 is also placed in the lumbar spine, and the existing single-anchor point screw unit 80 is used in other positions. One screw in the multi-anchor screw unit 100 may be placed using, for example, a cortical bone trajectory or a pedicle screw trajectory, and the other using, for example, a sacral wing trajectory. The connector 200 connects the single-anchor point screw units 80 and the multi-anchor point screw units 100 to form a stable lumbar spine fixation structure.

The two sets of multi-anchor point screw units 100 can also be used for bilateral fixation of the lumbar spine by combining multiple existing single-anchor point screw units 80 through the connector 200 . The use method is similar to that of lumbar unilateral fixation, and will not be repeated here.

Fig. 7 is a schematic diagram of a use state of the multi-anchor point screw assembly for bilateral fixation of the sacrum. As shown in FIG. 7 , there are fixed structures on both sides of the spine, that is, two connecting pieces 200 are used to fix and connect a plurality of single-anchor point screw units 80 and a multi-anchor point screw unit 100 on both sides respectively to form a stable structure. lumbar spine fixation structure. In each side of the connection, a multi-anchor screw unit 100 is placed in the sacrum. One screw in the multi-anchor screw unit 100 may be placed using, for example, a cortical bone trajectory or a pedicle screw trajectory, and the other using, for example, a sacral wing trajectory.

A set of multi-anchor point screw units 100 combined with a plurality of single screw units 80 through the connector 200 can also be used for unilateral fixation of the sacrum. The use method is similar to the bilateral fixation of the sacrum, and will not be repeated here.

Since the CT value (an index of anti-pullout strength) of the sacral pterygium screw is higher than that of the pedicle screw, setting two screws in the multi-anchor point screw unit can increase the occlusal area with the bone, and at the same time the bone where the screw is placed The density is higher than that of the cancellous bone where the traditional pedicle screw is placed, which can effectively improve the occlusal strength. Through the coordinated fixation of the main screw and the auxiliary screw, the two screws support each other and have a structural strength higher than that of a single screw. , but also to avoid damage to the sacroiliac joint.

A series of detailed descriptions listed above are only specific descriptions for the feasible embodiments of the present invention, and they are not intended to limit the protection scope of the present invention. Any equivalents made without departing from the technical spirit of the present invention The embodiments or changes should all be included within the protection scope of the present invention.

Claims (4)

1. A multi-anchor screw unit (100) for lumbar spine and sacral fixation, comprising: A main peg (10) comprising: a main peg body (12), and a main nail tail (14), which is fixedly connected with the main nail body (12); A screw seat (20) which includes: a main nail fixing part (22), which is provided with a main nail hole (222) and a connecting piece groove (224), the inner wall of the connecting piece groove (224) is provided with an internal thread, and a main nail tail cap (24), which rotatably defines the main nail tail (14) in the main nail hole (222), and is fixed in the main nail hole (222); and A connector tail cap (30), which is provided with an external thread matched with the internal thread of the connector groove (224); It is characterized by: The multi-anchor point screw unit (100) further includes: an auxiliary nail (40) and an auxiliary nail tail cap (50), and the screw seat (20) further includes an auxiliary nail fixing part (26), wherein: The auxiliary nail (40) includes an auxiliary nail body (42) and an auxiliary nail tail (44) that are fixedly connected, the auxiliary nail tail cap (50) is provided with an external thread, and the auxiliary nail fixing portion (26) ) is lower in height than the main nail fixing part (22), and has auxiliary nail holes (262) penetrating through its bottom, and the inner wall is provided with an inner thread matched with the external thread of the auxiliary nail tail cap (50). thread, the auxiliary nail body (42) is detachably penetrated through the auxiliary nail hole (262), and the auxiliary nail tail (44) is rotatably arranged in the auxiliary nail hole (262), and passes through the auxiliary nail hole (262). The auxiliary nail tail cap (50) is fixed. 2 . The multi-anchor point screw unit ( 100 ) according to claim 1 , wherein the surface of the auxiliary nail tail ( 44 ) is in the shape of a polyhedron or a rough surface. 3 . 3. A multi-anchor screw assembly for lumbar spine and sacrum fixation, characterized in that, comprising: a multi-anchor screw unit (100) as claimed in any one of claims 1 to 2, and A connecting piece (200), the connecting piece (200) can pass through the connecting piece groove (224), through the internal thread of the connecting piece tail cap (30) and the connecting piece groove (224) In cooperation, the connector (200) is connected with the multi-anchor point screw unit (100). 4. The multi-anchor point screw assembly according to claim 3, wherein the connecting member (200) is a connecting rod.

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