Additional fixation of pedicle screws in spinal segments

Abstract

An additional fixing device (1) can connect the pedicle screws (2, 200) of a spinal device (50) with the corresponding bone segments. Its main body (10) includes, on the one hand, a first fixing component (20) that directly or indirectly cooperates with the corresponding pedicle screw (2, 200) body, and on the other hand, a second fixing component (30) to ensure that the flexible strip (3) passes through and is fixed after being tensioned, thereby forming an additional anchoring point.

Description

[0001] The present invention relates to an additional fixation device which can connect at least one pedicle screw of a spinal device to a corresponding vertebra of a spinal column segment, thereby increasing the anchoring points of the spinal device on the vertebra.

[0002] According to the existing French patent FR3034979, a spinal fixation device for use on a spinal device connecting rod is known, comprising a pedicle screw and a fixing connection with a ring, which can implement the fixation of a flexible belt connecting the vertebrae.

[0003] The additional fixation means in the prior art are realized by means of flexible bands anchored on the bone rods of the spinal device.

[0004] Therefore, the disadvantage of the additional fixation device in the prior art is that it can ensure further anchoring at the end of the operation, ie after the spinal device is in place and the bone rods have been placed as the last step of the operation.

[0005] The additional fixation device is intended to increase the anchoring points of the spinal device before placement of the bone rod by ensuring a flexible connection under tension between the pedicle screw and the corresponding vertebral body.

[0006] The additional fixation device according to the present invention comprises a body which comprises, on the one hand, a first fixation component which directly or indirectly cooperates with a corresponding pedicle screw body, and, on the other hand, a second fixation component which ensures that the flexible strip passes through and is fixed after tensioning, thereby constituting an additional anchoring point.

[0007] The additional fixation device according to the invention comprises a body positioned coaxially with the main axis of the pedicle screw, such that the second fixation part is constituted on the one hand by a slit running vertically through the pedicle screw body and on the other hand by a threaded cap cooperating with the body to lock the flexible strip.

[0008] The additional fixation device according to the present invention comprises a threaded cap connected to a threaded shaft arranged in an extension of the vertical shaft of the pedicle screw to form a double-threaded pedicle screw.

[0009] The additional fixation device according to the invention comprises a body consisting of a sleeve, wherein a first fixation part is formed by a central hole and can be positioned on the hemispherical middle head of a double-threaded pedicle screw, while a second fixation part is arranged in a lateral extension of the sleeve in order to position and fix the flexible strip in a plane deviated from the vertical axis of the pedicle screw.

[0010] The additional fixation device according to the invention comprises a sleeve which is angularly indexed on the hemispherical head of the double-threaded pedicle screw.

[0011] The additional fixing device according to the invention comprises a second fixing part consisting of a joint in the sleeve extension, the bottom of which has a horizontal slot for the passage of the flexible strip and a fastening screw in the vertical direction for fixing the flexible strip after tensioning.

[0012] The additional fixing means according to the invention comprise a second fixing part consisting of a joint in the extension of the sleeve, which joint has a central opening situated in a horizontal plane and is divided into two distinct parts by a tightening ring so as to delimit two vertical channels for placing and fixing the tensioned flexible strip.

[0013] The additional fixation device according to the invention comprises a body consisting of a flange, which comprises, on the one hand, a first fixing part for ensuring the fixation of the flange on the periphery of the hemispherical head of the double-threaded pedicle screw, and, on the other hand, a second fixing part arranged in a lateral extension of the flange in order to position and fix the flexible strip in a plane deviating from the vertical axis of the pedicle screw.

[0014] The additional fixation device according to the invention comprises a first fixation member consisting of a deformable element to ensure elastic fixation on the periphery of the hemispherical head of the double-threaded pedicle screw.

[0015] The additional fixation device according to the invention comprises a first fixation member consisting of a mechanical element to ensure fixation on the periphery of the hemispherical head of the double-threaded pedicle screw by tightening.

[0016] The additional fixing means according to the invention comprise a second fixing part consisting of a joint in the flange extension having a central opening situated in a vertical plane and divided into two distinct parts by a tightening ring so as to define two channels for placing and fixing the tensioned flexible strip.

[0017] The additional fixing device according to the invention comprises a body consisting of a ring, which comprises, on the one hand, first fixing means for securing the flange on the periphery of the connecting joint, said connecting joint being freely mounted around the pedicle screw head, and, on the other hand, second fixing means arranged in the lateral extension of the ring in order to position and fix the flexible strip in a plane deviating from the vertical axis of the pedicle screw.

[0018] The additional fixation device according to the invention comprises a first fixation member consisting of deformable vertical branches to ensure elastic fixation on the periphery of the pedicle screw connection joint.

[0019] The additional fixing means according to the invention comprise a second fixing part consisting of a joint in the ring extension having a horizontal slot at the bottom for the passage of the flexible strip and a fastening screw in the vertical direction for fixing said flexible strip after tensioning.

[0020] The additional fixation device according to the invention comprises a body consisting of an open ring, which comprises, on the one hand, a first fixing part for ensuring the fixation of the open ring on the periphery of the hemispherical head of the double-threaded pedicle screw, and, on the other hand, a second fixing part arranged in a lateral extension of the open ring in order to position and fix the flexible strip in a plane deviating from the vertical axis of the pedicle screw.

[0021] The additional fixation device according to the present invention includes a first fixation component consisting of an open flexible sheet, the inner surface of which is provided with a groove, which cooperates with a convex pin arranged on the periphery of the hemispherical head of the double-threaded pedicle screw, the open flexible sheet includes an opening on its first free end, and the opposite second free end is connected to the second fixation component, the second fixation component is composed of a joint, the bottom of which has a horizontal slit and a fastening screw in the vertical direction.

[0022] The invention, its characteristics and possible advantages will be better understood through the following description with reference to the accompanying drawings and non-limiting examples:

[0023] [ Figures 1 to 3 ] is a schematic diagram of a first embodiment of an additional fixation device provided on a double-threaded pedicle screw according to the present invention.

[0024] [ Figures 4 to 6 ] is a schematic diagram of a second embodiment of an additional fixation device provided on the hemispherical middle head of the double-threaded pedicle screw according to the present invention.

[0025] [Figure 7 to Figure 8 ] is a schematic diagram of a first modification of an additional fixation device provided on the hemispherical middle head of a double-threaded pedicle screw according to the present invention.

[0026] [ Figures 9 to 14 ] is a schematic diagram of a second modification of an additional fixing device provided on the periphery of the hemispherical head of the double-threaded pedicle screw according to the present invention.

[0027] [ Figure 15 and Figure 16 ] is a schematic diagram of a third variant of an additional fixing device provided on the periphery of a connecting joint of a spinal device, wherein the spinal device corner is freely mounted around the head of a pedicle screw according to the present invention.

[0028] [ Figures 17 to 20 ] is a schematic diagram of a fourth modification of an additional fixation device provided on the hemispherical middle head of the double-threaded pedicle screw according to the present invention.

[0029] [ Figures 21 to 24] is a schematic diagram of the last modification of the additional fixation device provided on the hemispherical middle head of the double-threaded pedicle screw according to the present invention.

[0030] Figures 1 to 3 An additional fixation device 1 is shown, which can connect at least one pedicle screw 2 of a spinal device 50 to a corresponding vertebra of a spinal segment (not shown), thereby increasing the anchoring points of the spinal device on the vertebra.

[0031] The additional fixation device 1 according to the first embodiment comprises a body 10 which comprises, on the one hand, a first fixing part 20 cooperating with the body of the pedicle screw 2 and, on the other hand, a second fixing part 30 to ensure that the flexible strip 3 passes through and is fixed after tensioning, thereby constituting an additional anchoring point at the corresponding vertebra.

[0032] The second fixing member 30 of the main body 10 is positioned coaxially with the main axis of the pedicle screw 2. The second fixing member 30 of the main body 10 includes, on the one hand, a slit 31 extending vertically through the body of the pedicle screw 2 to allow the flexible strip 3 to pass through, and, on the other hand, a threaded cap 32 that is screwed onto the interior of the main body 1 to lock the tensioned flexible strip.

[0033] The threaded cap 32 is connected to the threaded shaft 33, which is arranged in the vertical axis extension of the pedicle screw 2 and in the opposite direction to the bone anchoring thread 4, thereby forming a double-threaded pedicle screw ( Figure 2 ).

[0034] Figures 4 to 6 An additional fixation device 1 according to a second embodiment is shown, which is arranged on a hemispherical middle head 5 of a double-threaded pedicle screw 2 .

[0035] The double-threaded pedicle screw 2 is a screw having a hemispherical head 5 and a mechanical threaded shaft 8 and a bone anchoring shaft 9 on both sides thereof and supported by the same main shaft. The mechanical threaded shaft 8 can be fixed to a connecting joint 51 of a spinal device 50 by a fastening nut 7, for example.

[0036] The additional fixation device 1 comprises a body 10 consisting of a sleeve 11 comprising a first fixation part 20 consisting of a central hole 21 which can be positioned on the hemispherical middle head 5 of the double-threaded pedicle screw 2 ( Figure 6 ).

[0037] It should be noted that the sleeve 11 can be graduated according to angle on the hemispherical head 5 of the double-threaded pedicle screw 2. The sleeve may include a protruding pin 12 ( Figure 6 ).

[0038] The sleeve 11 includes a second fixing member 30 provided in a lateral extension so as to position and fix the flexible strip 3 in a plane deviated from the vertical axis of the pedicle screw 2 .

[0039] The second fixing part 30 is formed by a joint 34 in the extension of the sleeve 11, the bottom of which has a horizontal slit 35 for the flexible strip 3 to pass through, and a fastening screw 36 in the vertical direction, which can fix the flexible strip after it is tightened ( Figure 6 ).

[0040] The sleeve 11 of the additional fixing device 1 is fixed in rotation and vertical translation on the hemispherical head 5 of the double-threaded pedicle screw 2 by means of a fastening nut 7 which is screwed onto a machine threaded shaft 8 on which a connection joint 51 is previously provided.

[0041] Figures 21 to 24 An embodiment variant of the additional fixation device 1 is shown, more specifically the above-described sleeve 11 arranged on the hemispherical middle head 5 of the double-threaded pedicle screw 2 .

[0042] The sleeve 11 comprises a first fixing member 20 consisting of a central hole 21 and can be positioned on the hemispherical middle head 5 of the double-threaded pedicle screw 2 .

[0043] The sleeve 11 includes a second fixing member 30 provided in a lateral extension so as to position and fix the flexible strip 3 in a plane deviated from the vertical axis of the pedicle screw 2 .

[0044] The second fixing part 30 is constituted by a joint 34 in the extension of the sleeve 11 , the bottom of which has two horizontal slits 37 and 38 passing through the joint 34 along two different axial directions intersecting the center thereof.

[0045] Two horizontal slits 37, 38 allow the free strands 3a, 3b of the flexible strip 3 to pass through respectively, so that the flexible strip crosses inside the joint 34 and passes out of the joint in the axial direction of the slits, so that the flexible strip 3 forms a retaining loop 3c.

[0046] The joint 34 comprises a vertical threaded hole 39 above the horizontal slits 37 , 38 for cooperating with a fastening screw 36 , which can fix the tensioned strands 3 a , 3 b of the flexible strip 3 inside the sleeve 11 when the fastening screw is tightened.

[0047] Figures 7A to 7C and Figure 8 A first embodiment variant of the additional fixation device 1 is shown, more particularly relating to the sleeve 11 and its arrangement on the hemispherical medial head 5 of the double-threaded pedicle screw 2 .

[0048] The second fixing part 30 of the sleeve 11 is constituted by a joint 40 having a central opening 41 situated in a horizontal plane and divided into two distinct parts by a fastening ring 42 so as to delimit two vertical channels 41 a and 41 b , to place and secure the tensioned flexible strip.

[0049] Figures 9 to 14 A second variant of the additional fixation means 1 provided on the periphery of the hemispherical head 5 of the double-threaded pedicle screw 2 according to the invention is shown.

[0050] The main body 10 of the additional fixation device 1 is composed of a flange 60, which includes, on the one hand, a first fixing part 20 to ensure the fixation of the flange 60 on the periphery of the hemispherical head 5 of the double-threaded pedicle screw 2, and, on the other hand, a second fixing part 30 arranged in the lateral extension of the flange 60 so as to position and fix the flexible strip 3 in a plane deviating from the vertical axis of the pedicle screw.

[0051] The first fixing member 20 of the flange 60 may be formed by a deformable element 61 ( Figure 12 ) or convex pin 62( Figure 10 ) is constructed to ensure elastic fixation on the periphery of the hemispherical head 5 of the double-threaded pedicle screw 2.

[0052] The deformable element 61 or the protruding pin 62 cooperates with the recess 6 ′ provided on the periphery of the lower portion of the hemispherical head 5 .

[0053] In fact, in this case, the flange 60 is positioned to penetrate the bone anchoring shaft 9 of the double-threaded pedicle screw 2 to be fixed below the hemispherical head 5 ( Figures 9 to 12 ).

[0054] The second fixing part 30 of the flange 60 is constituted by a joint 63 in the flange extension, which joint has a central opening 64 situated in a vertical plane and is divided into two distinct parts by a fastening ring 65 so as to delimit two channels 64 a and 64 b , to place and fix the tensioned flexible strip 3 ( Figure 10 and 12 ).

[0055] According to a modification, the first fixing member 20 can be constituted by a mechanical element 67, so that the flange 60 internally includes a thread 66 to ensure that it is fixed on the periphery of the hemispherical head 5 of the double-threaded pedicle screw 2 by tightening ( Figure 13 and 14 ).

[0056] Figure 15 and Figure 16A third variant of an additional fixation device 1 arranged on the periphery of the connection joint 51 of a spinal device 50 , which is freely mounted around the head 201 of a pedicle screw 200 , is shown.

[0057] The body 10 of the additional fixation device 1 is constituted by a ring 70 having first fixing means 20 to secure said ring on the periphery of the U-shaped connection joint 52 , which is freely mounted around the head 201 of the pedicle screw 200 .

[0058] The first fixing member 20 is formed by a deformable vertical branch 71 to ensure elastic fixation on the periphery of the connection joint 52 of the pedicle screw 200. The free end of the vertical branch 71 is connected to a lug 72 to ensure the retention of the ring 70 around the connection joint 51 ( Figure 16 ).

[0059] The ring 70 includes a second fixing member 30 provided in a lateral extension of the ring in order to position and fix the flexible strip 3 in a plane deviated from the vertical axis of the pedicle screw 200 .

[0060] The second fixing part 30 is formed by a joint 73 in the extension of the ring 70, the bottom of which has a horizontal slit 74 for the flexible strip 3 to pass through, and a fastening screw 75 in the vertical direction, which can fix the flexible strip after it is tightened ( Figure 16 ).

[0061] Figures 17 to 20 A fourth variant of an additional fixation device 1 arranged on a hemispherical head 5 of a double-threaded pedicle screw 2 is shown.

[0062] The body 10 of the additional fixation device 1 is constituted by an open ring 80 having a first fixing part 20 for securing the open ring 80 on the periphery of the hemispherical head 5 of the double-threaded pedicle screw 2 .

[0063] The split ring 80 includes a second fixing member 30 disposed in a lateral extension to position and fix the flexible strip 3 in a plane offset from the vertical axis of the pedicle screw.

[0064] The first fixing member 20 is composed of an elastic open flexible sheet 81, the inner surface of which is provided with a groove 82, which cooperates with a convex pin 83 provided on the periphery of the hemispherical head 5 of the double-threaded pedicle screw 2 ( Figure 20 ).

[0065] The open flexible sheet 81 includes an opening 84 at its first free end, and the opposite second free end is connected to the second fixing member 30, which is composed of a joint 85 having a horizontal slit 86 at the bottom and a fastening screw 87 in the vertical direction ( Figure 20 ).

[0066] The flexible strip 3 of the additional fixing device 1 is introduced through the opening 84 and the slit 86 and, when tightened, allows the flexible sheet 81 to approach the open ring 80 around the hemispherical head 5, while the tightening screw 87 ensures the fixing of the flexible strip and thus locks the open ring around the hemispherical head ( Figure 19 ).

[0067] It should also be noted that the above description is only given as an example and does not limit the scope of the present invention. Any equivalent replacement of the described implementation details will not depart from the scope of the present invention.

Claims

1. An additional fixation device (1) capable of connecting the pedicle screws (2) of a spinal device (50) to the corresponding bone segments before placing the bone rod of the spinal device (50), characterized in that The additional fixing device comprises a main body (10), which comprises a first fixing part (20) that directly or indirectly cooperates with the corresponding pedicle screw (2) on the one hand, and a second fixing part (30) on the other hand to ensure that the flexible strip (3) passes through and is fixed after being tensioned, thereby forming an additional anchor point. wherein the main body (10) is constituted by a sleeve (11), wherein the first fixing member (20) is constituted by a central hole (21) capable of being positioned on the hemispherical middle head (5) of the pedicle screw (2), and the second fixing member (30) is arranged in a side extension of the sleeve (11) so as to position and fix the flexible strip (3) in a plane deviating from the vertical axis of the pedicle screw (2), and The second fixing part (30) is composed of a joint (34) in the extension of the sleeve (11), and the bottom of the joint has two horizontal slits (37, 38), which pass through the joint in two different axial directions and intersect with the center of the joint (34).

2. The additional fixing device according to claim 1, characterized in that The main body is graduated in angles on the hemispherical head (5) of the pedicle screw (2) by a sleeve (11).

3. The additional fixing device according to claim 1, characterized in that The second fixing component (30) is composed of a joint (34) in the extension of the sleeve (11), the bottom of which has a horizontal slit that allows the flexible strip (3) to pass through, and a fastening screw (36) in the vertical direction that can fix the flexible strip (3) after it is tensioned.

4. The additional fixing device according to claim 1, characterized in that The joint (34) includes a vertical threaded hole (39) above the horizontal slits (37, 38) for cooperating with a fastening screw (36) so that the tensioned flexible strip (3) can be placed inside the sleeve (11) when the fastening screw is tightened.

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