阅读说明：本技术 可扩张多轴脊柱内固定系统 (Expandable multi-axial spinal internal fixation system ) 是由 乌里·阿宁 于 2016-04-12 设计创作，主要内容包括：一种脊柱椎弓根螺钉系统,该脊柱椎弓根螺钉系统具有在螺钉(26)插入到椎弓根中之后被分开并经由多轴接头(22)维持运动的能力。(A spinal pedicle screw system having the ability to be distracted and maintain motion via a polyaxial joint (22) after insertion of a screw (26) into a pedicle.)

1. An spinal internal fixation system (10), comprising:

a first separator bar (12) having a first connector (14) mounted at an end thereof, an

Characterized by a coupling member (20) and a second separator bar (16),

wherein the second separator bar (16) has a second connector (18) mounted at an end thereof,

wherein each of the separator bars (12, 16) is arranged to rotate in the coupling (20),

wherein each of the separator rods (12, 16) is arranged for longitudinal translation within the coupling (20) independently of rotation within the coupling (20);

wherein each of the connectors (14, 18) is mounted on a respective one of a pair of polyaxial joints (22) and secured by a respective one of a pair of fasteners (24),

wherein each of the polyaxial joints (22) is attached to a respective one of a pair of pedicle screws (26), and

wherein when the fasteners (24) are all tightened against the respective polyaxial joint (22), the connectors (14, 18) are not free to be removed from the respective polyaxial joint (22) and the polyaxial joint (22) remains free to polyaxially manipulate.

2. The spinal internal fixation system (10) according to claim 1, characterized by comprising a pair of spaced apart fasteners (28, 30), wherein at least one of the spaced apart bars (12, 16) is arranged to be fixed in the coupling (20) at any desired longitudinal translational position by one of the spaced apart fasteners (28, 30).

3. An intraspinal fixation system (10) according to claim 2, characterized in that at least one of the distraction rods (12, 16) is arranged to be fixed in any desired rotational position in the coupling (20) by one of the distraction fasteners (28, 30).

4. An intraspinal fixation system (10) as claimed in claim 3, wherein the coupling (20) is configured to separate the separator rods (12, 16) using a fluid.

5. The spinal internal fixation system (10) according to claim 4, characterized in that said fluid is selected from the group consisting of water, saline or air.

6. The spinal internal fixation system (10) according to claim 5, wherein the coupling (20) comprises a fluid inlet (52), the fluid inlet (52) being configured to receive the fluid therethrough.

7. An spinal internal fixation system (10) according to claim 3, wherein the coupling (20) comprises a biasing device (62), the biasing device (62) being arranged to exert a biasing force on at least one of the distraction rods (12, 16).

8. The spinal internal fixation system (10) according to claim 7, wherein the biasing device (62) comprises a spring.

9. The spinal internal fixation system (10) according to claim 7, wherein at least one of the fasteners (62) comprises a nut.

10. An spinal internal fixation system (10), comprising:

a first separator bar (12) having a first connector (14) mounted at an end thereof,

characterized by a coupling member (20) and a second separator bar (16),

wherein the second separator bar (16) has a second connector (18) mounted at an end thereof,

wherein each of the separator bars (12, 16) is arranged to rotate in the coupling (20),

wherein each of the separator rods (12, 16) is arranged for longitudinal translation within the coupling (20) independently of rotation within the coupling (20);

wherein each of the connectors (14, 18) is mounted on a respective one of a pair of polyaxial joints (22) and secured by a respective one of a pair of fasteners (24),

wherein each of the polyaxial joints (22) is part of a respective one of a pair of pedicle screws (26), and

wherein when the fasteners (24) are all tightened against the respective polyaxial joint (22), the connectors (14, 18) are not free to be removed from the respective polyaxial joint (22) and the polyaxial joint (22) remains free to polyaxially manipulate.

11. The spinal internal fixation system (10) according to claim 10, characterized by comprising a pair of spaced apart fasteners (28, 30), wherein at least one of the spaced apart bars (12, 16) is arranged to be fixed in the coupling (20) at any desired longitudinal translational position by one of the spaced apart fasteners (28, 30).

12. The spinal internal fixation system (10) according to claim 11, characterized in that at least one of the distraction rods (12, 16) is arranged to be fixed in any desired rotational position in the coupling (20) by one of the distraction fasteners (28, 30).

13. The spinal internal fixation system (10) according to claim 12, characterized in that the coupling (20) is arranged to separate the distraction rods (12, 16) using a fluid.

14. The spinal internal fixation system (10) according to claim 13, wherein the fluid is selected from the group consisting of water, saline, or air.

15. The spinal internal fixation system (10) according to claim 14, wherein the coupling (20) comprises a fluid inlet (52), the fluid inlet (52) being configured to receive the fluid therethrough.

16. The spinal internal fixation system (10) according to claim 12, wherein the coupling (20) comprises a biasing device (62), the biasing device (62) being arranged to exert a biasing force on at least one of the distraction rods (12, 16).

17. The spinal internal fixation system (10) according to claim 16, wherein the biasing device (62) comprises a spring.

18. The spinal internal fixation system (10) according to claim 10, wherein at least one of the fasteners (62) comprises a nut.

Technical Field

The present invention relates generally to spinal implants and prostheses, and in particular to spinal pedicle screw-based systems designed to be expandable and maintain polyaxial motion in situ.

Background

Scoliosis is affecting a large proportion of the population. Current surgical treatments many times involve the use of intervertebral pedicle screw-based systems designed to be placed between two or more vertebrae.

The use of standard pedicle screw systems is often associated with spinal fusion, which has some known negative effects. Therefore, it would be valuable to have a non-fusion system that can prevent or correct some patients for lateral protrusions.

Disclosure of Invention

The present invention seeks to provide an improved spinal pedicle screw-based system that is capable of expanding and maintaining spinal motion via one or more polyaxial joints after the screw is inserted into the pedicles of two vertebrae.

There is therefore provided, in accordance with a non-limiting embodiment of the present invention, an spinal internal fixation system, including: a first separator bar having a first connector mounted at an end thereof; and a second spreader bar having a second connector mounted at an end thereof, the two bars each being arranged to move in the housing, and wherein each of the connectors is mounted on a polyaxial joint and secured by a fastener, each of the polyaxial joints being attached to or part of a pedicle screw, and wherein the fastener is tightened against a portion of the polyaxial joint but does not inhibit polyaxial movement of the polyaxial joint such that the connector cannot be removed from the polyaxial joint even after the fastener is tightened, but the polyaxial joint is always free to polyaxially move.

According to an embodiment of the invention, at least one of the first and second separator bars is fixed at any desired position along the housing by a separator fastener.

According to an embodiment of the invention, at least one of the first and second separator bars is rotated about its longitudinal axis before being locked in position by the separator fastener.

According to an embodiment of the invention, at least one of the separating rods is at least partially threaded and cooperates with an internal thread in the housing.

According to an embodiment of the invention, two of the separating rods are each at least partially threaded and cooperate with an internal thread in the housing, and wherein the thread of one of the separating rods is right-handed and the thread of the other separating rod is left-handed.

According to an embodiment of the invention, the housing comprises a fluid inlet for introducing fluid through the fluid inlet.

According to an embodiment of the invention, the housing comprises a biasing device operable to exert a biasing force on at least one of the first and second split bars.

Drawings

The invention will be more fully understood and appreciated from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a simplified pictorial illustration of an internal spinal fixation system, constructed and operative in accordance with a non-limiting embodiment of the present invention, in an initial collapsed configuration prior to distraction;

FIG. 2 is a simplified illustration of the spinal internal fixation system in an expanded/distracted configuration;

FIG. 3 is a simplified cross-sectional view of the system in its expanded/separated configuration;

FIG. 4 is a simplified pictorial illustration of an internal spinal fixation system, constructed and operative in accordance with another non-limiting embodiment of the present invention, wherein separation is performed using a threaded member;

FIG. 5 is a simplified pictorial illustration of an internal spinal fixation system, constructed and operative in accordance with another non-limiting embodiment of the present invention, wherein the distraction is performed using hydraulic or pneumatic pressure; and is

FIG. 6 is a simplified pictorial illustration of an internal spinal fixation system, constructed and operative in accordance with another non-limiting embodiment of the invention, in which distraction is performed using a biasing element.

Detailed Description

Reference is now made to fig. 1-3, which illustrate an spinal internal fixation system 100, constructed and operative in accordance with a non-limiting embodiment of the present invention.

The spinal internal fixation system 10 includes: a first split bar 12, the first split bar 12 having a first connector 14 mounted at an end thereof; and a second separator bar 16, the second separator bar 16 having a second connector 18 mounted at an end thereof. The two rods 12 and 16 are arranged to move (e.g., translate or slide) within the housing 20. The two connectors 14 and 18 may each include a ring mounted on a multi-axis joint 22 (which may be, but is not limited to, a spherical head) and secured by a fastener 24 (e.g., a nut). The polyaxial joint 22 may be attached to the pedicle screw 26 or may be part of the pedicle screw 26. The fastener 24 is tightened against a portion (upper portion in the illustration) of the polyaxial joint 22, but does not inhibit polyaxial movement of the polyaxial joint. Thus, even though the connector 14 or 18 cannot be removed from the polyaxial joint after tightening the fastener 24, the polyaxial joint is always free to polyaxially move.

The split fasteners 28 and 30 may secure the first and second split bars 12 and 16, respectively, at any desired location along the housing 20.

After inserting the pedicle screws 26 into the patient's vertebrae, the distance between the screws (the two terms being used interchangeably) can be separated or expanded by using a distractor (not shown) or any other suitable means. The separated orientation is shown in fig. 2. After separation, the separation fasteners 28 and 30 can be used to fix the distance between the pedicle screws.

As seen in fig. 1 and 2, first and second separator rods 12 and 16 may be rotated about their respective longitudinal axes before being locked in place by separator fasteners 28 and 30. For example, only one of the split bars may be rotated without rotating the other split bar, or both split bars may be rotated. As another example, only one of the split bars may be split without the other split, or both may be split. The rod that is not split may be locked in place by the split fastener or, alternatively, may remain unlocked, in which case the rod is free to move in translation and rotation.

Reference is now made to FIG. 4, which illustrates an internal spinal fixation system constructed and operative in accordance with another non-limiting embodiment of the present invention, wherein like elements are designated by like reference numerals. In this embodiment, the separator rods 42 and 44 are at least partially threaded and mate with internal threads 46 in the housing 20. The separation may be performed by rotating the rod relative to the housing, i.e. by rotating the rod with the housing stationary or by rotating the housing without rotating the rod, or by rotating both the rod and the housing. In one embodiment, threads 43 of rod 42 are right-hand threads and threads 45 of rod 44 are left-hand threads. In this manner, rotating the housing in one direction causes the bars 42 and 44 to move simultaneously in opposite directions. After separation to the desired distance between the pedicle screws, separation fasteners (not shown) may be used to secure the system at the desired location.

Reference is now made to FIG. 5, which illustrates an internal spinal fixation system constructed and operative in accordance with another non-limiting embodiment of the present invention, wherein like elements are designated by like reference numerals. In this embodiment, the separation is performed using hydraulic or pneumatic pressure. For example, the housing 20 may be provided with a fluid inlet 52 for introducing a fluid (e.g., water, saline, air, etc.) through the fluid inlet 52. Fluid pressure acts on the rods 12 and 16 and increases the distance between the rods 12 and 16. A sealing ring (not shown) may be provided to seal the fluid in the housing 20. The fluid may be introduced during the surgical procedure or at any point in time after the surgical procedure.

In one embodiment, one of the rods can be fixed to the housing while the other rod is separated by fluid force (hydraulic or pneumatic).

Reference is now made to FIG. 6, which illustrates an internal spinal fixation system constructed and operative in accordance with another non-limiting embodiment of the present invention, wherein like elements are designated by like reference numerals. In this embodiment, the separation is performed using a biasing device 62 (e.g., a coil spring or a flexible band) disposed in the housing. The biasing device 62 may be made of a metal or an elastomeric material. The biasing device 62 may apply a constant or varying spring force on the rods 12 and 16.

In one embodiment, one of the bars can be fixed to the housing while the other bar is separated by a spring force.