AN EXPANDABLE CAGE

Abstract

An expandable cage which is used in spinal surgery and which allows adjustment of distance between two vertebrae in which it is placed as preferred. An expandable cage-basically includes at least one body which is located in emptied area between damaged vertebrae during the surgical procedure and serves as a disc; and at least one movable element which is located on the body and is fitted in the opening made in the body by means of the retainers disposed at the sides thereof; which has a toothed surface contacting with the upper vertebra and being attached to it; and the height of which can be adjusted by pushing the protrusion provided in the lower portion thereof according to the intervertebral distance of patient by means of the expansion apparatus.

Claims

1. An expandable cage configuration that preserves the distance between two vertebrae as preferred during cervical surgical procedures, can be implanted easily, does not cause any infection, and can be used in patients with different body and bone type due to the height-adjustable structure thereof, characterized by: at least one body which is located in the emptied area between the damaged vertebrae during the surgical procedure and serves as a disc, at least one movable element which is located on the body and is fitted in the opening made in the body by means of retainers disposed at the sides thereof; which has a toothed surface contacting with the upper vertebra and being attached to it; and the height of which can be adjusted by pushing a protrusion provided in the lower portion thereof according to the intervertebral distance of the patient by means of an expansion apparatus.

2. An expandable cage as in claim 1, characterized by a body which comprises at least one upper surface fitted in the upper vertebra and having sparks on the surface thereof, at least one lower surface fitted in the lower vertebra and having a spark on the surface thereof, lateral surfaces provided at both sides of the body, at least one front surface facing towards the inside of the body according to the vertebrae to which it is positioned, and at least one rear surface facing towards the outside of the body according to the vertebrae to which it is positioned.

3. An expandable cage as in claim 1, characterized by a front inner wall which is arranged in parallel to the front surface in the emptied area within the body and has a certain thickness and a height which is shorter than that of the front surface.

4. An expandable cage as in claim 1, characterized by a barrier which is disposed on the front inner wall in the emptied area between the front inner wall and the front surface and to which one end of the movable element is engaged when the latter is raised.

5. An expandable cage as in claim 1, characterized by a side inner wall which is preferably provided thereon with lugs and inserts and which is joined perpendicular to the front inner wall and rear inner wall forming the emptied area within the body, said side inner wall also being parallel to the lateral surfaces.

6. An expandable cage as in claim 1, characterized by a lug which has a “cam” form being raised in upward direction from the lower portion of the side inner wall and is arranged on the side inner wall; which also presents the portion in which the movable element is fitted at the preferred height; and which preserves the movable element to stabilize at the preferred height.

7. An expandable cage as in claim 1, characterized by an insert which is the portion in which the retainers provided at the sides of the movable element are fitted in the position where the movable element, which is placed in the emptied portion inside the body, is not preferred to be raised; which is positioned in the lower portion of the lugs disposed on the side inner walls; and which is arranged perpendicular to the lugs and parallel to the lower inner wall.

8. An expandable cage as in claim 1, characterized by a rear inner wall which is parallel to the rear surface and provided thereon with a barrier.

9. An expandable cage as in claim 1, characterized by a barrier which hinders the upward movement of the upper portions of the retainers, and thus maintains the movable element at the preferred height stable.

10. An expandable cage as in claim 1, characterized by a lower inner wall which is the lower portion of the emptied area within the body; which is arranged such that it will be parallel to the lower surface and will be within the body; and which serves a base for the expansion apparatus so that the expansion apparatus located inside the body and used for raising the movable element will elevate the movable element to the preferred height.

11. An expandable cage as in claim 1, characterized by a movable element which is located in the opening which is made in the body and surrounded by a front inner wall, preferably by two opposed side inner walls and rear inner walls, wherein the lower portion of said opening is closed by the lower inner wall.

12. An expandable cage as in claim 1, characterized by a protrusion which is the component with which the expansion apparatus contacts during the elevation of the movable element, which is positioned in the body, in upward direction by means of the expansion apparatus which at the same time enables the user to rotate the expansion apparatus clockwise and counterclockwise in a way to elevate the movable element.

13. An expandable cage as in claim 1, characterized by a retainer which is fitted in the lugs when the movable element is not raised within the body; and which is fitted and fixed in the emptied area between the front inner wall and front surface when the movable element is elevated to the preferred height by means of the expansion apparatus.

14. An expandable cage as in claim 1, characterized by an inlet which is formed in the rear surface of the body by emptying a portion of said rear surface; whereby the expansion apparatus is introduced into the body when it is preferred to raise the movable element.

15. An expandable cage as in claim 1, characterized by a movable element which, subsequent to being raised until the barriers disposed in the front inner wall and rear inner wall, is fitted in the lugs disposed on the side inner walls, and then being locked in this position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0017] An expandable cage developed for achieving the objects of the present invention is illustrated in the accompanying drawings, in which;

[0018] FIG. 1. Perspective view of the expandable cage.

[0019] FIG. 2. Perspective view of the expandable cage from another angle.

[0020] FIG. 3. Bottom perspective view of the expandable cage.

[0021] FIG. 4. Perspective view of the body.

[0022] FIG. 5. Perspective view of the body from another angle.

[0023] FIG. 6. Perspective view of the body from another angle.

[0024] FIG. 7. Perspective cross-sectional view of the expandable cage.

[0025] FIG. 8. Perspective view of the movable element.

[0026] FIG. 9. Bottom perspective view of the movable element.

[0027] FIG. 10. Perspective view of the expandable cage and expansion apparatus.

[0028] The components in the drawings are enumerated individually and the reference numbers corresponding thereto are given below.

[0029] 1. An expandable cage

[0030] 2. Body [0031] 2.1. Upper surface [0032] 2.1.1. Spark [0033] 2.2. Lower surface [0034] 2.2.1. Spark [0035] 2.3. Lateral surface [0036] 2.4. Front surface [0037] 2.5. Rear surface [0038] 2.6. Front inner wall [0039] 2.7. Side inner wall [0040] 2.8. Rear inner wall [0041] 2.9. Lower inner wall [0042] 2.10. Barrier [0043] 2.11. Lug [0044] 2.12. Joint [0045] 2.13. Inlet [0046] 2.14. Horizontal hole

[0047] 3. Movable element [0048] 3.1. Retainer [0049] 3.2. Toothed surface [0050] 3.3. Protrusion

[0051] A. Expansion apparatus

[0052] An expandable cage (1) configuration that preserves the distance between two vertebrae as preferred during cervical surgical procedures, can be implanted easily, does not cause any infection, and can be used in patients with different body and bone type due to the height-adjustable structure thereof, basically comprises: [0053] at least one body (2) which is located in the emptied area between the damaged vertebrae during the surgical procedure and serves as a disc, and [0054] at least one movable element (3) which is located on the body (2) and is fitted in the opening made in the body (2) by means of the retainers (3.1) disposed at the sides thereof; which has a toothed surface (3.2) contacting with the upper vertebra and being attached to it; and the height of which can be adjusted by pushing the protrusion (3.3) provided in the lower portion thereof according to the intervertebral distance of the patient by means of the expansion apparatus (E).

[0055] In an embodiment of the invention, there exists a body (2). The body (2) is located between the vertebrae and serves the same function as the damaged and removed disc. The body (2) mainly comprises at least one upper surface (2.1) fitted in the upper vertebra and having sparks (2.1.1) on the surface thereof, at least one lower surface (2.2) fitted in the lower vertebra and having sparks (2.2.1) on the surface thereof, lateral surfaces (2.3) provided at both sides of the body (2), at least one front surface (2.4) facing towards the inside of the body according to the vertebrae to which it is positioned, and at least one rear surface (2.5) facing towards the outside of the body according to the vertebrae to which it is positioned.

[0056] In order to locate the movable element (3), a portion of the body is emptied at sufficient dimensions such that the movable element (3) will be positioned therein. The emptied portion is provided with a front inner wall (2.6) which is arranged parallel to the front surface (2.4). The front inner wall (2.6) has a certain thickness in parallel to the front surface (2.4) and a height which is shorter than that of the front surface (2.4). One side of the movable element (3) is fitted in the space remaining between the front inner wall (2.6) and the front surface (2.4).

[0057] There exists a barrier (2.10) on the front inner surface (2.4) in the emptied area between the front inner wall (2.6) and the front surface (2.4). When the movable element (3) is raised, the retainer (3.1) disposed at its one side is engaged in said barrier (2.10).

[0058] In an embodiment of the invention, two opposed side inner walls (2.7) that are joined perpendicularly to the front inner wall (2.6) and rear inner wall (2.8) forming the emptied area within the body (2). The side inner walls (2.7) are arranged in parallel to the opposed lateral surfaces (2.3). The side inner wall (2.7) is preferably provided thereon with lugs (2.11) and inserts (2.12). The lug (2.11) disposed on the side inner wall (2.7) is the portion in which the movable element (3) is fitted at the preferred height (FIG. 7). In this embodiment of the invention, the side inner wall (2.7) is provided thereon with two lugs (2.1) which are preferably located adjacently. Moreover, the opposed side inner walls (2.7) are provided a total number of four lugs (2.11) thereon. In another embodiment of the invention, the shape and dimensions of the lug (2.11) may vary according to the form of the lower surface of the movable element (3) located thereon. The lugs (2.11) stably maintains the movable element (2) at the preferred height. In this embodiment of the invention, the lug (2.11) is raised upwards from the lower portion of the side inner wall (2) at a certain angle and has a “cam” shape. In this embodiment of the invention, the lugs (2.11) are provided by shaping the side inner walls (2.7). In alternative embodiments of the invention, the lugs (2.11) are manufactured separately from the body (2) and may be mounted in the side inner walls (2.7).

[0059] In an embodiment of the invention, the insert (2.12) is disposed in the lower portion of the lugs (2.11) provided on the side inner walls (2.7). The insert (2.12) is arranged in the lower portion of the lugs (2.11) such that it will be perpendicular to the lugs (2.11) and parallel to the lower inner wall (2.9). The insert (2.12) is the portion in which the retainers (3.1) provided at the sides of the movable element (3) are fitted in the position where the movable element (3), which is placed in the emptied portion inside the body (2), is not preferred to be raised.

[0060] In an embodiment of the invention, there exists a rear inner wall (2.8) forming the emptied area within the body (2). The rear inner wall (2.8) is parallel to the rear surface (2.5) and provided thereon with a barrier (2.10). The retainer (3.1) disposed at one side of the movable element (3), which is preferred to be raised during the surgical operation, is fitted in the space between the front inner wall (2.6) and front surface (2.4), and then engaged in the barrier (2.10) provided thereon as well as in the barrier (2.10) on the rear inner wall (2.8) opposite said barrier (2.10). The barriers (2.10) hinder the upward movement of the retainers (3.1) from the upper portions thereof, and thus maintaining the movable element (3) at the preferred height stably.

[0061] In an embodiment of the invention, there exists a lower inner wall (2.9) presenting the lower portion of the emptied area within the body (2). The lower inner wall (2.9) is arranged parallel to the lower surface (2.2). The lower inner wall (2.9) serves a base for the expansion apparatus (E) so that the expansion apparatus (E) located inside the body (2) and used for raising the movable element (3) will elevate the movable element (3) to the preferred height.

[0062] In an embodiment of the invention, a movable element (3) is located in the opening which is made in the body (2) and surrounded by a front inner wall (2.6), preferably by two opposed side inner walls (2.7) and rear inner walls (2.8), wherein the lower portion of said opening is closed by the lower inner wall (2.9).

[0063] The movable element (3) is a component whose height can be elevated in the body (2) in case it is required to increase the intervertebral distance during the surgical operation. The movable element (3) has a size that allows it to be placed in the body (2), preferably being of a certain height. The movable element (3) consists of retainers (3.1) enabling it to be fixed inside the body (2), at least one toothed surface (3.2) contacting with the upper vertebra, and at least one protrusion (3.3) which is disposed in its lower surface and with which the expansion apparatus (E) contacts. The toothed surface (3.2) enables the movable element (3) to be attached in the upper vertebra. The protrusion (3.3) is the component with which the expansion apparatus (E) contacts during the elevation of the movable element (3), which is positioned in the body (2), in upward direction by means of the expansion apparatus (E). The user rotates the expansion apparatus (E) clockwise or counterclockwise by way of the protrusion (3.3), and thus making it raise. The retainers (3.1) at the sides of the movable element (3), a portion of which is preferably elevated in upward direction, are fitted in the lugs (3.11) without being raised inside the body (2). When the movable element (3) is elevated to the preferred height by means of the expansion apparatus (E), the retainers (3.1) are engaged in the barriers (3.10); and the retainer (3.1) at one side of the movable element (3) is fitted and fixed in the emptied area between the front inner wall (2.6) and front surface (2.4). In this embodiment of the invention, the retainers (3.1) are provided by shaping the edges of the movable element (3).

[0064] In another embodiment of the invention, the retainer (3.1) may be a component that is mounted in the movable element (3), wherein it enclosed by the movable element (3) and is mounted in the movable element (3) such that the movable element (3) will be located in the body (2) and prevented from being displaced.

[0065] In an embodiment of the invention, the rear surface (2.5) of the body (2) is provided with an inlet (2.13). The inlet (2.13) is formed by emptying a portion of the rear surface (2.5). When it is preferred to elevate the movable element (3) during the application, the expansion apparatus (E) is placed in the body (2) through the inlet (2.13), contacts with the protrusion (3.3) in the lower surface of the movable element (3), whereby the movable element (3) is raised until the barriers (2.10) disposed in the front inner wall (2.6) and rear inner wall (2.8).

[0066] The implanting process of an expandable cage (1) according to the invention is as follows: after the damaged intervertebral disc is removed, the region of the disc is cleaned. Subsequent to cleaning, the body (2) and the movable element (3) thereon are located between the vertebrae such that the front surface (2.4) of said body (2) will face towards the inside of the body. Afterwards, the expansion apparatus (E) is positioned inside the body (2) through the inlet (2.13) disposed in the rear surface (2.5) of the body (2) in accordance with the distance between the vertebrae. In such position, the expansion apparatus (E) is in contact with the protrusion (3.3) provided in the lower surface of the movable element (3). The expansion apparatus (E) is rotated clockwise or counterclockwise at a certain angle. With the rotation of the expansion apparatus (E), the protrusion (3.3) with which it is in contact, and hence the movable element (3) can be brought to the preferred height. After the movable element (3) is raised until the barriers (2.10) disposed in the front inner wall (2.6) and rear inner wall (2.8), it is fitted in the lugs (2.11) disposed on the side inner walls (2.7). When the movable element (3) is in this position, the upper portion of the retainers (3.1) at two opposed sides thereof is delimited by the barriers (3.10) while the lower portion of the other two opposed sides is delimited by the lugs (2.11), whereby it is locked in such position. After the preferred intervertebral distance is adjusted, the expansion apparatus (E) is retracted through the inlet (2.13) and the positioning of the expandable cage (1) between the vertebrae is thus completed.

[0067] In an embodiment of the invention, the component in which the rear inner wall (2.8) and the rear surface (2.5) are provided may be manufactured separately from the body (2). In this case, such component is mounted in the body (2) through the horizontal holes (2.14) disposed on the rear surface (2.5).

[0068] With an expandable cage (1) according to the invention, the movable element (3) can be locked between the vertebrae at the preferred height. The expandable cage (1) fills in the area between the two vertebra in which it is applied, and is fused with the bones, and thus enables the patients to continue their daily lives shortly after the implementation. The expandable cage (1) can be made of various materials, said materials being biocompatible. The materials of which the expandable cage (1) is made are also capable of carrying post-implementation loads.

[0069] An expandable cage (1) according to the invention differs from the cage designs used in the art due to its simple design, having a locking mechanism, ability to be applied in a short time, and allowing the patients to continue their daily lives immediately after the implementation.