JP2017213262A - Bone retainer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bone retainer capable of reliably fixing a bone element.SOLUTION: A bone retainer comprises: a base 20 that has a first space 21 for holding a rod 7; a hook 30 that forms a second space 31 for receiving a bone element 5 in cooperation with a part of the base 20; and a sandwich body 40 that is attached to the base 20 to sandwich the bone element 5 received into the second space 31 in cooperation with a part of the hook 30. The sandwich body 40 can be moved to be capable of coming into contact with the bone element 5.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a bone fixation device that is connected to a rod and fixed to a bone.

  For example, a common spinal fixation method performed to correct and stabilize spinal curvature is to fix the spine using a pair of bendable rods placed parallel to the spine. These rods are fitted with several fixing means along the spinal column, such as hooks and screws that are fixed to various thrusts.

  In this way, the rod can be used in combination with fixing means such as hooks or screws to fix vertebrae or other bone elements to each other.

  By the way, the bone hook as a fixing means includes a main body that accommodates the rod and a hook having a curved arm, the rod is fixed to the main body, and the bone element of the vertebra is hooked and fixed to the arm. (See Patent Document 1).

JP 2002-528218 A

  Since a general bone hook as described above is usually hooked and fixed to a bone element, it is easy to come off, and it is not screwed into the bone like a bone screw. Can not be fixed.

  Therefore, the present invention has been made with the above problem as an example of an object, and provides a bone fixation device that can reliably fix a bone element.

  In order to solve the above problems, the present invention employs the following configuration. In order to facilitate understanding of the present invention, reference numerals in the drawings are given in parentheses, but the present invention is not limited thereto.

  That is, the bone anchoring device (S) according to claim 1 includes a base (20) having a first space (21) for holding the rod (7), and a bone element in cooperation with a part of the base. (5) A hook (30) forming a second space (31) for receiving, and a bone element attached to the base and receiving the bone element received in the second space in cooperation with a part of the hook And a sandwiching body (40), wherein the sandwiching body is movable in contact with the bone element.

  The bone fixation device according to claim 2 is characterized in that in the bone fixation device according to claim 1, the bone element is sandwiched between a pair of surfaces formed by a sandwiching body and a part of a hook.

  The bone anchoring device according to claim 3 is the bone anchoring device according to claim 1 or 2, wherein the base portion is an opening that communicates with the first space that accommodates the rod from the outside. 11), and a closing body (15) for closing the opening is detachably attached to the opening.

  The bone fixation device according to claim 4 is the bone fixation device according to any one of claims 1 to 3, wherein the sandwiching body can be inclined according to a shape of a bone element. And

  After the bone element is received in the space formed in the hook, the bone element is brought into contact with the bone element, and the bone element is clamped in cooperation with the hook in the space. it can.

It is a schematic diagram which shows the state which attached the bone fixing apparatus to the bone element of the spine. It is a schematic diagram which shows the structural example of a bone fixing device. It is a side view of a bone fixing device. It is a schematic diagram which shows the longitudinal cross-section of a bone fixing device, and shows the attachment state of a clamping body.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the bone fixing apparatus shown below demonstrates as the bone hook S used in the spinal fixation method performed for the correction | amendment and stabilization of a spinal curvature as an example. For convenience, the left-right direction shown in FIG. 3 will be described as the front-rear direction of the bone hook S.

  As shown in FIG. 1, the bone hook S of the present embodiment is coupled to an elongated cylindrical rod 7 disposed along the spine 2, sandwiching a bone element 5 such as a protrusion on the vertebra 3, and The spine 2 is fixed together with a plurality of screws and other bone hooks S (not shown) coupled to the unit 7. Each screw is screwed into each vertebra 3 and fixed, and the bone hook S fixes the bone element 5 so that the spine 2 or other bone elements 5 are fixed to each other.

  As shown in FIG. 2, the bone hook S includes a main body 10 having an opening 11 at the upper end, and a set screw 15 (occluding body of the present application) that closes the opening 11. , Titanium or other suitable body compatible metal material.

  The main body 10 includes a base portion 20 having a space portion 21 (first space of the present application) in which the rod 7 can be accommodated and a hook 30 extending below the base portion 20, and the base portion 20 and the hook 30 are integrated. Is formed.

  The base portion 20 includes a side wall 23 that forms the space portion 21 by surrounding a side portion, and a bottom body 24 that closes a lower end of the side wall 23. The front and rear side walls 23, 23 include the space portion 21. A substantially U-shaped slot 25 is formed. The slot 25 communicates with the opening 11, and the rod 7 can be inserted from the opening 11 along the slot 25. The rod 7 is accommodated in the space portion 21.

  The upper inner wall surface of the left and right side walls 23 has an inner surface 26 formed in an arc shape in plan view, and an inner screw 27 is formed on the inner surface 26.

  As shown in FIG. 2, the set screw 15 is formed in a substantially cylindrical shape, and an outer screw 16 that is screwed with the inner screw 27 is formed on the outer peripheral surface thereof. The upper end surface of the set screw 15 has a concave portion 17 as an engaging portion that can be engaged with a polygonal tool, and the main body 10 can be rotated by attaching a predetermined tool to the concave portion 17. The set screw 15 can be detached.

  The main body 10 and the rod 7 are firmly fixed by attaching the set screw 15 to the opening 11 and pressing the rod 7 downward by the lower end surface of the set screw 15 so as to be held in the space 21.

The hook 30 is used, for example, to fix the bone element 5 of the vertebra 3 and has an arm 33 in which a space portion 31 (second space of the present application) for receiving the bone element 5 is formed. The space 31 has an opening for receiving the bone element 5 from the side in cooperation with the base 20.

  The arm 33 includes a curved portion 34 that extends downward from the base portion 20 and a flat portion 35 that is disposed substantially parallel to the bottom body 24 of the base portion 20, and includes the bottom body 24 of the base portion 20, the curved portion 34, and the flat portion 35. The bone element 5 can be received from the side in the space portion 31 formed by the portion 35.

  Note that the flat portion 35 or the bottom body 24 does not need to be formed in a particularly flat shape, and the bending portion 34 does not need to be particularly curved, and is a space for receiving the bone element 5 by the bottom body 24 and the arm 33 of the base portion 20. If is formed, its shape is not limited.

  In this way, the bone element 5 of the vertebra 3 can be inserted into the space portion 31 through the side opening and is received in the space portion 31 of the hook 30.

  Further, below the base portion 20, a clamping body 40 for clamping the bone element 5 received in the space portion 31 in cooperation with the flat portion 35 of the hook 30 is provided.

  The sandwiching body 40 is attached to the base portion 20 so as to be movable in the vertical direction, and can contact the bone element 5 inserted into the space portion 31 of the hook 30. The sandwiching body 40 includes a main body 42 having a predetermined thickness and formed in a substantially circular shape in plan view, and a shaft 45 for moving the main body 42 in the vertical direction. The main body 42 and the shaft 45 are pinned. 46. The main body 42 and the shaft 45 are sandwiched by a pin 46 with a predetermined gap, and the main body 42 is attached with a backlash by this gap.

  As shown in FIG. 4, a through hole 51 extending in the vertical direction is formed on the bottom body front side of the base 20, and the shaft 45 is inserted into the through hole 51. An inner screw 52 is formed on the inner surface of the through hole 51, and an outer screw 53 that can be screwed with the inner screw 52 is formed on the outer periphery of the shaft 45. Then, as shown by an arrow in FIG. 4, for example, the shaft 45 is screwed into the through hole 51 by the clockwise rotation of the main body 42, and the main body 42 is separated from the flat portion 35 of the arm 33, while the main body 42. The counterclockwise rotation causes the shaft 45 to be taken out from the through hole 51 and the main body 42 approaches the flat portion 35 of the arm 33.

  Accordingly, the distance between the main body 42 and the flat portion 35 of the hook 30 can be adjusted by the rotation of the main body 42 in a predetermined direction, and the sandwiching body 40 is inserted into the space portion 31 of the hook 30. Depending on the size of the bone element 5, the main body 42 is moved in a predetermined direction to come into contact with the bone element 5, and the bone element 5 is clamped between the main body 42 and the flat portion 35 to fix the bone element 5. Let

  As described above, the bone hook S of the present embodiment presses the bone element 5 from above and below by sandwiching the bone element 5 received in the space portion 31 of the hook 30 between the flat portion 35 and the main body 42 of the hook 30. And fix. Since the bone element 5 is sandwiched between the surface of the main body 42 of the sandwiching body 40 and the surface of the flat portion 35 of the hook 30, the bone element 5 can be firmly fixed.

  Further, the shaft 45 and the main body 42 of the sandwiching body 40 are coupled by a pin 46 and attached with a predetermined backlash, and the periphery of the sandwiching body 40 can be moved up and down by this backlash. It is possible to incline at a predetermined angle with the pin 46 as a fulcrum. In the bone hook S of the present embodiment, because of the looseness, the sandwiching body 40 is easily brought into contact with the bone element 5 on the surface. It is possible to fix the bone element 5.

  Although not shown, the surface of the pin 46 that contacts the main body 42 of the sandwiching body 40 is curved in a convex shape, and a predetermined gap is provided between the main body 42 and the shaft 45 to connect with the above-described form. In comparison, the main body 42 can be inclined at a desired angle, and the main body 42 can be inclined according to the external shape of the bone element 5, and the bone element 5 having a slight unevenness on the surface can be strengthened. It becomes possible to pinch.

  In the present embodiment, the main body 42 and the shaft 45 of the sandwiching body 40 are provided separately and connected by pin coupling, but may be formed integrally. Further, the coupling method of the main body 42 and the shaft 45 is not limited to the pin coupling, and any method may be used as long as it is a generally known coupling method.

  In addition, by making the length of the shaft 45 longer than the length of the through hole 51, the shaft 45 is easily exposed in the space portion 21 in which the rod 7 is accommodated. In this way, in the state in which the rod 7 is attached, the shaft 45 is pressed by the lower end surface of the rod 7, so that the movement of the main body 42 due to the rotational movement of the shaft 45 can be easily prevented. It is possible to stably maintain the fixed state of the bone element 5 as compared with the above.

  Next, an example of the action of the bone hook S will be described. In the present embodiment, a method in which a predetermined bone element 5 is fixed by the bone hook S by a general spinal fixation method performed for correcting and stabilizing the spinal curvature will be described.

  First, the main body 10 from which the set screw 15 has been removed with a predetermined tool by the operator is attached to a predetermined position of the rod 7 disposed on the spine 2. Specifically, after the rod 7 is inserted from the opening 11 of the base portion 20 and the rod 7 is accommodated in the space portion 21, the set screw 15 is attached to the opening 11 with a predetermined tool. In this state, in order to make it easier to receive the bone element 5 in the space portion 31 of the hook 30, the set screw 15 is temporarily fixed so that the main body 10 can rotate about the rod 7 as a fulcrum.

  Next, according to the position of the bone element 5, the base 20 attached to the rod 7 is rotated to adjust the position of the hook 30, and at the same time the bone element 5 is received in the space portion 31 of the hook 30, The main body 42 of the holding body 40 is rotated in a predetermined direction and moved downward according to the size of 5, is brought into contact with the bone element 5, and the bone element 5 is held between the main body 42 and the flat portion 35 of the hook 30.

  Then, the set screw 15 is rotated in a predetermined direction and screwed into the opening 11 to perform the main fixing, and the process ends. As a result, the rod 7 is pressed downward by the set screw 15 and comes into contact with the bottom body 24 of the base portion 20 to fix the rod 7 to the main body 10, and the bone element 5 is firmly held by the hook 30 and the holding body 40. Fixed to.

  In addition, this embodiment is one form and is not limited to this form. For example, in this embodiment, the opening 11 is formed in the upper portion and the rod 7 can be inserted from the opening 11, but the opening 11 may be formed in the side wall 23. Further, the shape of the hook 30 can be changed as appropriate, and any shape may be used as long as the predetermined space portion 31 having an opening on the side and having a region for receiving the bone element 5 is formed. In addition, the shape of the main body 42 of the sandwiching body 40 is circular in consideration of ease of holding in the present embodiment, but may be any shape.

S ... Bone hook 5 ... Bone element 7 ... Rod 30 ... Hook 21, 31 ... Space part 40 ... Clamping body

Claims (4)

A base having a first space for holding a rod;
A hook that cooperates with a portion of the base to form a second space for receiving a bone element;
A sandwiching body attached to the base and sandwiching a bone element received in the second space in cooperation with a part of the hook;
The bone anchoring device is characterized in that the clamping body is movable so as to come into contact with the bone element.   The bone fixing device according to claim 1, wherein the bone element is sandwiched between a pair of surfaces formed by a sandwiching body and a part of a hook. The base has an opening communicating with the first space for accommodating the rod from the outside, and a closing body for closing the opening is detachably attached to the opening. Or a bone anchoring device according to claim 2.   The bone fixing device according to any one of claims 1 to 3, wherein the sandwiching body can be tilted according to a shape of a bone element.

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