JP2017159069A - Lamina arcus vertebrae reinforcement implant comprising cantilever shape bridge part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcement implant inserted into lamina arcus vertebrae of vertebra.SOLUTION: A reinforcement implant comprises a main body part including a seat surface against vertebra and a fixation device. A cantilever part 2 laid on an ablation part 92 of lamina arcus vertebrae 91 is provided. Anchor parts are arranged on each of opposing edges of the bridging part. The first anchor part is configured to have a pressure surface 30 sitting on spinous process 90 of the vertebra. The second anchor part is configured to have a thrust inclined surface 40 sitting on the outer surface of the lamina arcus vertebrae 91. An angle between the pressure surface 30 and the thrust inclined surface 40 is an obtuse angle α. A slide prevention device, specifically an intervertebral screw 50, is provided on the thrust inclined surface 40. One edge of the thrust inclined surface 40 is adjacent to an anti-load part 20 of the cantilever part 2 overlapping the ablation part 92 of the lamina arcus vertebrae 91.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lamina reinforcing implant having a cantilever bridge.

  The human or animal spinal column is composed of a plurality of vertebrae that overlap each other. These are connected to each other so as to realize load resistance and articulation. To that end, the vertebrae comprise a solid vertebral body with two osteoprojections (pedicles). The two bone processes protrude laterally and towards the posterior side and are connected at their posterior part by an osseoarch. In its connecting region, the bone arch is widened (a lamina) and is provided with a spinous process at its center projecting backwards. The spinous process on the side of the pedicle and two additional transverse processes form the joint points of muscles and ligaments. In the region where the pedicle joins the lamina, the upper and lower articular processes are located on both sides. These form part of the facet joint for adjacent upper and lower vertebrae. In order to make load bearing connections to adjacent upper and lower vertebrae, the intervertebral discs, respectively, are placed on a flat surface on the bottom side or the top side of the vertebral body. The space surrounded by the posterior side of the vertebral body and the lamina forms a hollow space (vertebral canal) that contains nerve fibers that run parallel to the spinal column. It has been shown that when nerve fibers are pinched or trapped, especially due to bone growth in the spinal canal area or disc protrusion (so-called disc herniation), pressure is applied to the nerve fibers, thereby causing unbearable back pain .

  As a treatment, it is known to at least partially open the lamina to create an access path in the spinal canal. The growth causing this problem is suppressed, for example, by known instruments, thereby removing the pressure acting on the nerve fibers. The pain caused by pressure is correspondingly reduced by this method. In the case of this method already known as laminectomy or decompression, the access formed in the lamina, i.e. the gap present in the lamina, in most cases does not close after surgery. This has been shown to reduce the mechanical stability of the vertebrae.

  Applicants have proposed an available implant set having a plurality of reinforcing implants of various sizes in a prior patent application. These include a diamond-shaped filler body that is inserted and filled into a gap formed by laminectomy. The rhombus-shaped filler body abuts on the two opposing side surfaces of the cut portion of the lamina. By this method, the lamina returns to its original complete state by inserting the filler body, and can again resist the load, and is not particularly buckled by the compressive load. In order to be able to fill the excision as completely as possible without expanding, it is necessary to prepare a considerable number of different sizes (at least seven) for each side (left or right) of the reinforcing implant. This makes the implant set quite complex. Furthermore, with respect to the required function for transmitting pressure, it is important that the side of the filler body that abuts the cutting surface of the lamina is as flat as possible. Actually, the cut surface is not flat, so the pressure is not transmitted sufficiently. As yet another consideration, it is difficult to insert the filler body when the cut surface is not a surface, which can lead to a more complicated situation.

  The object of the present invention is to provide an improved reinforcing implant which can be used to overcome these problems.

  The solution according to the invention lies within the features of the independent claims. Advantageous changes form the subject of the dependent claims.

  A reinforcing implant that is inserted into the vertebral lamina has a body with a seating surface for the vertebrae and a fixation device. According to the present invention, a cantilever portion that spans the excision portion is provided, and an anchor portion is provided at each of opposing ends of the cantilever portion. Further, the first anchor portion is configured to have a pressure surface that is seated on the spinous process of the vertebra, and the second anchor portion is configured to have a thrust slope surface that is seated on the outer surface of the lamina. Has been. Furthermore, the angle between the pressure surface and the thrust slope is an obtuse angle. Furthermore, a slip prevention device, specifically a face screw, is arranged on the thrust ramp. One edge of the thrust slope is adjacent to the load-bearing portion of the cantilever portion that spans the cut portion of the lamina.

  The present invention is based on the use of a special anchor to hang a permanent bridge, which is actually sturdy and easy to implant, on the part of the resected lamina. The use of two bearing surfaces oriented at an obtuse angle relative to each other, ie, a pressure ramp as one and a thrust ramp as the other, provides a stable and unconstrained holding configuration for all spatial dimensions. The This arrangement avoids static overdetermination, such as conventional implants with two pressure surfaces facing each other substantially parallel to each other (especially implants designed as filler bodies). The intrinsic elasticity of the bone is taken into account in this way and is thereby maintained without being limited by constraints. This implant therefore behaves more physiologically. This also not only behaves favorably, but also means that the useful life of the implant is increased by avoiding denaturation. Very hard implants are actually constrained implants that have been found to easily denature bones that are not currently stressed.

  Furthermore, the implant according to the invention can be easily handled when implanting itself. It does not need to be inserted into the free space formed by the laminectomy, but instead is mounted in place from the outside so as to span the free space. To that end, the implant is placed on one side of the pressure surface facing the side of the spinous process of the vertebra and on the other side against the outer surface of the lamina and secured via a slip prevention device. And a thrust slope. Thereby, the implant need not be pushed into the free space at all. Therefore, there is no load applied to the actual excision surface formed by excision of the lamina. Therefore, in reality, undesirable cut surface irregularities that often occur in surgery do not affect the positioning or fixation of the implant.

  The cantilever portion of the reinforcing implant is preferably configured such that the portion transmitting the load from the thrust slope to the pressure surface does not intersect the plane defined by the thrust slope. This means that the load bearing part of the cantilever part does not protrude into the free space formed by the excision of the lamina, so that the bridge part is completely outside. Therefore, it is possible to remarkably suppress the stimulation that occurs due to the transmission of the load from the thrust slope to the pressure surface and particularly acts on the excised portion of the sensitive lamina.

  For the sake of convenience, the reinforcing implant is configured such that the plurality of anchor portions are in the form of first and second rims connected via cantilever portions. This rim structure can reduce the amount of material used for the implant and the space occupied by the implant. By reducing the space, the impact on surrounding cells can be minimized, thereby minimizing the possibility of inflammation caused by the implant. The pivot pin pivot joint is preferably disposed on at least one of the plurality of rims. The fixing pin is understood in particular as a screw or a bone fin. By this pivot joint, the axis of the fixing pin can be freely adjusted within a predetermined range. It has been found that an adjustment range of 15 degrees in each direction with respect to the center position (“normal position”) is preferred.

  The pivot joint preferably comprises a cup-shaped receiving seat and a ring attached to it and guiding a stationary pung. The cup-shaped configuration allows stepless turning with low friction when the fixing pin is loose, and self-locks when the fixing pin is in the fastened state.

  In particular, the ring preferably includes an anti-rotation portion that holds the ring so as not to rotate with respect to the seat of the pivot joint. Undesirable ring rotation in the pivot joint is prevented by using this type of rotation barrier. When the fixing pin is a screw and the screw is fastened, undesired rotation can customarily occur. At that time, it is not preferable that the ring rotate too much. By using the anti-rotation portion, the ring is not restricted for being able to turn, but the rotation about the axis of the fixed pin is suppressed.

  For convenience, the pivot joint is configured such that the fixing pin can move at least 10 ° in each direction about the normal position, and at most 20 °. When the angle of the adjustment range is too large, there is a possibility that the fixing reliability and the positioning accuracy are lowered. On the other hand, when the range of adjustment is small, the requirement for sufficient versatility of the reinforcing implant according to the present invention may not be satisfied.

  The two rim pivot joints are preferably configured in such a way that the two rim fixing pins in the normal position lie on one plane. This ensures that the fixed surface extends in exactly the same way on both rims. On the other hand, if the fixed pins are twisted outside the common plane, static overdetermination can lead to constraints. This can be effectively prevented by arranging them on a common plane.

  The anti-skid device is preferably in the form of a screw that is oriented in the normal position to deviate by a maximum of 30 °, preferably at least 10 °, relative to the normal of the thrust ramp. Obviously, with such an arrangement, the two objectives can be interrelated. One object is to adequately secure the reinforcing implant according to the present invention avoiding unfavorable positions relative to the lamina. The other purpose is to direct the screw so that it is fixed to the mechanically strong bone part when connected to the facet joint part of the adjacent vertebra in the sacral direction (ie towards the base of the spine) It is to attach. By using a long screw that reaches the adjacent lower vertebra, a so-called intervertebral screw, it is possible to fix and simultaneously join the facet joints. Thereby, the facet joint is fixed on this side. If not intended for fixation, a short screw that does not reach the adjacent lower vertebra is sufficient.

  The cantilever part of the reinforcing implant is provided with a wing-like extension part protruding from the edge of the thrust slope. The wing extension is preferably parallel to the pressure surface. The pterygium extension itself is not load bearing and protrudes into the free space formed in the lamina by resection. This facilitates insertion of the implant under difficult conditions. Depending on the size of the pterygium extension, invasion of bone residues and other undesirable materials from the outside into the spinal canal of the vertebra can be suppressed. For this purpose, various sizes are preferably prepared for the winged extension.

  The winged extension is preferably configured to have a planar outer surface facing away from the pressure surface, and preferably includes reinforcing ribs on the inner surface facing the pressure surface. The outer surface is configured to sit on a portion of the lateral resection surface of the lamina, but does not need to be seated under pressure against the resection surface of the lamina. The smaller the gap between them, the more the material can be prevented from entering. The wing-like extension part is formed integrally with the cantilever part for convenience. Further reinforcing ribs are provided on the inner surface for mechanical strength. In the implanted state, this reinforcing rib is located in the free space formed by the resection and does not contact the lamina.

  The winged extension is preferably located at the transition from the thrust ramp to the cantilever, and specifically extends up to half the width of the thrust ramp. This achieves maximum coverage by the pterygium extension without excessive entry into the ablation space or into the spinal canal where nerve fibers extend and are surrounded by the lamina. The wing extension is preferably configured such that its lower edge is inclined with respect to the axis of the slip prevention device. This means that the lower edge moves away from the thrust slope as it goes downward. Optimum coverage is achieved by an extension having such a downward projecting configuration.

  The wing extension can be prepared for emergencies thanks to the planar configuration of the outer surface and thanks to the reinforcing ribs preferably provided on the inner surface. If the fixation via the bridge part is loosened, for example due to breakage of the anti-slip device, the lamina with the resection surface is supported only by moving to a position where it is seated on the planar outer surface of the winged extension at most. This ensures that damage to the vertebral arch and its dramatic impact on the patient are avoided.

  The invention further relates to an implant set comprising a plurality of reinforcing implants according to the invention of various sizes and inserted into the vertebral lamina. Each of the reinforcing implants has a main body portion having a seating surface for the vertebra and a fixing device, provided with a cantilever portion that spans the excision portion of the lamina, and provided with an anchor portion at each of the opposing ends of the cantilever portion, The first anchor portion is configured to have a pressure surface seated on the spinous process of the vertebra, and the second anchor portion is configured to have a thrust slope seated on the outer surface of the lamina, The angle between the thrust slope is obtuse and an anti-slip device, specifically an intervertebral screw, is placed on the thrust slope, and one edge of the thrust slope is located on the cantilever part that spans the resection of the lamina. Adjacent to the load bearing.

  For detailed description and further optional embodiments, reference is made to the description of the individual reinforcing implants described above.

The invention will be described on the basis of an exemplary embodiment and with reference to the accompanying drawings,
FIG. 1 is a bottom view of an embodiment of a reinforcing implant according to the present invention, FIG. 2 is a plan view (a) and a side view (b) of the reinforcing implant with the intervertebral screw inserted. FIG. 3 is a top view of two types of reinforcing implants of various sizes. Side view (a) and top view (b) of the reinforcing implant of the second embodiment, Side view (a) and top view (b) of the reinforcing implant of the third embodiment, The figure which shows the vertebra (a) provided with the laminectomy part, and the vertebrae (b) and (c) into which the reinforcing implant according to the second embodiment of FIG. 4 is inserted.

  A first embodiment of a reinforcing implant according to the present invention is shown in FIG. It is designated as a whole by 1. It is substantially rim-shaped and comprises a first rim 3 and a second rim, which are connected to each other by a bridge part 2.

  To better understand the present invention, the structure of the vertebra and the essential interaction between the reinforcing implant and the vertebra are described in detail below. In particular, reference is made to FIGS. The vertebra 9 includes a solid vertebral body 98 with two laterally projecting osteoprojections 97, which are connected in their posterior region by a bone arch. Yes. The bone arch has a lamina 91, and a process (spinous process) 90 extending to the rear side in the center. In the transition region to the lamina 91, the upper and lower articular processes are located on both sides and form part of the facet joints 95, 95 'with respect to the adjacent lower vertebra 9'. The vertebra 9 is also connected to the adjacent lower vertebra by an intervertebral disc 99. Intervertebral disc 99 is placed in a load-bearing state between the lower surface of vertebral body 98 and the corresponding upper surface of adjacent vertebra 9 '.

  As is clear from the rear view of FIG. 6A, a free space 92 exists on the right side of the spinous process 90 in the portion of the lamina 91. This free space is formed by resection, resulting in the formation of corresponding resection surfaces 93, 94 on the left and right lamina 91 of free space 92. The gap created by this free space 92 forms an access to the spinal canal 96. It is closed and mechanically stable by using the reinforcing implant according to the invention.

  As shown in FIGS. 6 (a) and 6 (b), the reinforcing implant according to the present invention is attached to a predetermined position of the lamina 91 from the rear, for example, from the buttock direction. Specifically, the first rim 3 is mounted on the spinous process 90 and the second rim 4 is seated on the rear surface of the portion of the lamina 91 on the right side of the resection surface 94. The right implantation is illustrated in FIGS. 6 (a) -6 (c). By using a reinforcing implant with a suitable mirror image configuration (see FIG. 3), left-side implantation is possible as well.

  In order to fix the reinforcing implant 1 to the vertebra 9, a pressure surface 30 is provided on the outer surface of the first rim 3. The pressure surface 30 is substantially planar. A thrust ramp 40 is provided on the outer surface of the second rim 4 and is configured to sit on the outer surface of the lamina 91 of the vertebra 9. A slip prevention device 5 is provided on the thrust slope 40. In the illustrated example embodiment, it has spikes 51 (only two are shown, but fewer or more are possible) and intervertebral screws 50 (see FIG. 2). The intervertebral screw 50 is oriented so that in the normal position, the angle γ between its axis 55 and the normal 67 of the thrust ramp 40 is 30 °.

  The intervertebral screw 50 includes a head portion 52, a shaft portion 53 on which no screw is formed, and a bone thread portion 54 at the tip thereof. The length of the unthreaded shaft portion 53 is such that the latter half of the intervertebral screw 50 is completely within the proximal portion of the facet joint 95, while the adjacent lower vertebra 9 The length is such that only the portion of the shaft portion including the bone screw portion 54 is present in the portion of the facet joint on the far side. As an effect of this, when the screw 50 is fastened, the portion of the facet joint 95 on the far side is pulled toward the head 52 of the screw under the force of the bone screw part 54, thereby Supported on the proximal portion. Thereby, reliable fixation of the facet joint 95 is realized.

  A second intervertebral screw 50 ′ is inserted into the first rim 3. The intervertebral screw 50 'is oriented to align with the facet joint 95' located on the other side of the vertebra. The structure of the second intervertebral screw 50 ′ corresponds in principle to that of the intervertebral screw 50. It has a head portion 52 ', a shaft portion 53' that is not threaded, and a bone screw portion 54 '. The length of the shaft portion 53 ′ where no screw is formed is significantly longer than that of the shaft portion 53. This is because the distance to the opposite facet joint 95 'is significantly long. The second intervertebral screw 50 'is also referred to as a translaminar screw.

  When the fixation of the reinforcing implant 1 is simplified, it is not necessary to fix the facet joints 95, 95 ′, and the screws 50, 50 ′ are in a range that can be completely received in the vertebra 9, ie adjacent to the lower part. It is shortened ("short screw") so that it does not protrude into the part of the facet joint on the other side of the vertebra 9 '. A special screw with a thread formed over the entire length of the shaft may be used.

  Intervertebral screws 50, 50 'are not securely attached to the first and second rims 3, 4 so that they can be rotated about the screw axis, specifically at an angle of 15 ° in both directions. It has been. For this purpose, pivot joints 6 are provided on the rims 3, 5 for the intervertebral screws 50, 50 ', respectively. The pivot joint 6 includes a cup-shaped seat 60 and a ring 61 that has a spherical jacket surface and engages the seat 60.

  The shapes of the two rims 3 and 4 are configured such that the outer surfaces thereof have an obtuse angle α, and the pressure surface 30 and the thrust slope 40 are disposed thereon. The angle α is preferably between 95 ° and 125 °, and is 110 ° in the exemplary embodiment shown in the figure. Thanks to the obtuse angle, the reinforcing implant can be implanted from the back side, thereby bridging the free space 92 formed by resection of the lamina 91. For this purpose, the reinforcing implant 1 has a second rim 4 with a thrust ramp against the rear surface of the lamina 91. Thereby, one anchor part is formed. The other anchor portion is formed by the first rim 3, and the first rim 3 has a pressure surface. The pressure surface is pressed by the side surface of the spinous process 90 of the vertebra 9. Therefore, the cantilever part 2 located between the two rims 3 and 4 functions like a bridge over the free space 92 formed by cutting. The force transfer line between the two rims 3, 4 passes through the load bearing 20 of the cantilever part 2, and specifically, the load flow is generated completely outside the free space 92. pass. Structurally, this means that the force transmission line in the load bearing 20 extends so as not to intersect the plane 24 defined by the thrust ramp 40 and extends only outside this area (ie the rear side). Means.

  In order to securely fix the second rim 4 with the thrust bevel 40 to the lamina 91, in particular to prevent undesired shearing movement relative to the lamina 91, the anti-slip device 5 is provided with spikes 51 and It is provided in both forms of an intervertebral screw 50 as a fixing pin. Each of the above two devices is itself sufficient to stop the undesired shearing movement. An intervertebral screw 50 is provided to improve fixation reliability and to prevent the thrust slope 40 from lifting from the outer surface of the lamina 91. The screw 50 need not have the length shown in FIG. 2 in order to suppress unwanted shearing movement. A shorter screw 50, which is short enough to stay completely within the vertebra 9, is sufficient. When the screw 50 is intended for fixation of the facet joint 95, the length of the screw 50 is such that the threaded portion 54 protrudes from the vertebra 9 and penetrates into the adjacent lower vertebra 9 ', thereby causing the facet joint 95. The length is fixed.

  In the second and third embodiments of the reinforcing implant according to the present invention, as shown in FIGS. 4 and 5, a wing-like extension portion 7 is additionally provided. Reference is made to FIGS. 4 (a) and 4 (b). The wing extension part 7 protrudes from the thrust slope 40. In particular, it is arranged at the lower third of the thrust slope 40 at the transition between the second rim 4 and the cantilever part 2, ie at the transition between the thrust slope 40 and the cantilever part 2. The wing extension portion 7 is oriented so as to be parallel to the pressure surface 30 of the first rim 3. The wing extension part 7 is provided with a flat surface on the outer surface 70 facing the thrust slope 40 side. A reinforcing rib 71 is provided on the inner surface on the opposite side facing the pressure surface 30 side. The wing-like extension portion 7 includes the second rim 4 integrally with the lower portion of the second rim 4 so as to protrude substantially obliquely downward (when the reinforcing implant 1 ′ is embedded). The lower edge 72 is oriented to tilt outward relative to the axis 55 of the intervertebral screw 50 attached to the second rim 4. The tilt angle β is between 15 ° and 20 °, and is about 18 ° in the illustrated embodiment. The winged extension 7 projecting diagonally downward protects the spinal canal 96 bounded by the lamina 91 from the invasion of bone fragments formed especially during resection of the free space 90. For the patient, the undesirable invasion of this type of bone fragment has the negative effect of reinducing a compressive load on the nerve fibers extending through the spinal canal 96 as a result of not being able to obtain the desired outcome of the surgery. Occur.

  A further function of the wing-like extension portion 7 is to play a role of increasing mechanical rigidity. On the other hand, a bridge portion 20 is also provided to improve the mechanical stability. The wing-like extension part 7 is configured integrally with the bridge part 20. Thanks to its planar outer surface 70, it can be seated on the cut surface 94. There is no need to sit under pressure. However, the smaller the gap between them, the more the invasion of the substance, particularly the bone fragment, can be suppressed as described above. If the gap is made as small as possible, there is an advantage that the wing-like extension part 7 can function as an emergency seat. When the fixation of the bridge portion 20 on the anchor portion of the second rim 4 becomes loose (for example, when the slip prevention device 5 is damaged due to the intervertebral screw 50 being broken or the like), the lamina 91 having the resection surface 94 is At most, it only moves to a position where it is seated on the planar outer surface 70 of the wing-like extension portion 7, thereby being supported by the wing-like extension portion 7, thereby suppressing damage.

  5 (a) and 5 (b) show a third embodiment. When compared to the second embodiment shown in FIGS. 4 (a) and 4 (b), the only difference is that a larger wing extension 7 'is used. Therefore, the above description is applied to the second embodiment.

  The reinforcing implant 1 according to the present invention is preferably a part of an implant set as shown in FIG. Various types with different sizes are shown in a row. For each size, there are both a right implant (right hand half in FIG. 3) version and a left implant (left hand half in FIG. 3) version of the reinforcing implant. For each version, there are those without a wing extension, those with a small wing extension, and those with a large wing extension.

Claims (20)

A reinforcing implant to be inserted into the lamina (91) of the vertebra (9),
Having a body with a seating surface for the vertebrae and a fixation device;
A cantilever portion (2) is provided over the excision portion (92) of the lamina (91);
An anchor part is provided at each of the opposing ends of the bridging part,
The first anchor portion is configured to include a pressure surface (40) seated on the spinous process (90) of the vertebra (9);
The second anchor portion is configured to include a thrust ramp (40) seated on the outer surface of the lamina (91),
The angle between the pressure surface (30) and the thrust slope (40) is an obtuse angle (α),
A slip prevention device (5), in particular an intervertebral screw (50), is arranged on the thrust ramp (40),
A reinforcing implant, wherein one edge of the thrust ramp (40) is adjacent to the load bearing (20) of the cantilever part (2) that spans the resection (92) of the lamina (91).   The reinforcing part according to claim 1, wherein the portion (20) of the cantilever part (2) that transmits the load from the thrust slope to the pressure surface does not intersect the plane (24) defined by the thrust slope (40). Implant.   The body part comprises a first rim (3) on which the pressure surface (30) is arranged and a second rim (4) on which the thrust slope (40) is arranged. Reinforcing implant as described.   Reinforcing implant according to claim 3, characterized in that a pivot joint (6) for the fixing pin is arranged on at least one of the rims (3, 4).   5. Reinforcing implant according to claim 4, wherein the pivot joint (6) comprises a cup-shaped seat (60) and a ring (61) attached to it for guiding the fixing pin.   The reinforcing implant according to claim 5, wherein the ring (61) comprises an anti-rotation part for holding the ring against rotation with respect to the seat (60).   The pivot joint (6) is configured to reinforce according to any one of claims 3 to 6, wherein the fixing pin is configured to be movable in a range of 10 ° to 20 ° in each direction around a normal position. Implant.   The reinforcing implant according to claim 7, wherein the pivot joint (6) is configured such that the fixing pins of the two rims (3, 4) in the normal position lie on one plane.   Reinforcing implant according to claim 7 or 8, wherein the fixing pin is offset in the normal position by a maximum of 30 °, preferably at least 10 ° with respect to the normal of the thrust ramp (40).   The fixation pin in the pressure surface (40) is oriented in its normal position, in the implanted state, towards the facet joint (95 ') opposite the vertebra (9). The reinforcing implant according to claim 9.   11. The reinforcing implant according to claim 1, comprising a winged extension (7) projecting from the thrust ramp (40).   The reinforcing implant according to claim 11, wherein the winged extension (7) is parallel to the pressure surface (30).   The airfoil extension (7) includes a planar outer surface (70) facing away from the pressure surface (30), and preferably a reinforcing rib (71 on the inner surface facing toward the pressure surface (30). The reinforcing implant according to claim 11 or 12, comprising:   The reinforcing implant according to any one of claims 11 to 13, wherein the wing-like extension part (7) is arranged at a transition part from the thrust slope (40) to the cantilever part (2).   15. A reinforcing implant according to any one of claims 11 to 14, wherein the wing extension (7) extends up to half the width of the thrust ramp (40).   The reinforcing implant according to claim 11, wherein the lower edge (72) of the wing extension (7) is inclined with respect to the axis (55) of the anti-skid device. The fixing pin is a long or short screw (50, 50 '),
The long screw reaches into the adjacent lower vertebra (9 ')
17. A reinforcing implant according to any one of claims 7 to 16, wherein the short screw is not reached and its end is located in the vertebra (9). The shaft portion of the long screw includes a portion (53, 53 ′) where no screw is formed on the head side, and a screw portion (54, 54 ′) on the tip side,
18. A reinforcing implant according to claim 17, wherein the non-threaded portion is sized to reach the adjacent lower vertebra (9 '). An implant set to be inserted into the lamina (91) of the vertebra (9),
Including a plurality of reinforcing implants of various sizes,
Each of the reinforcing implants
Having a body with a seating surface for the vertebrae and a fixation device;
A cantilever portion (2) is provided over the excision portion (92) of the lamina (91);
An anchor part is provided at each of the opposing ends of the bridging part,
The first anchor portion is configured to include a pressure surface (40) seated on the spinous process (90) of the vertebra (9);
The second anchor portion is configured to include a thrust ramp (40) seated on the outer surface of the lamina (91),
The angle between the pressure surface (30) and the thrust slope (40) is an obtuse angle (α),
A slip prevention device (5), in particular an intervertebral screw (50), is arranged on the thrust ramp (40),
The implant set, wherein one edge of the thrust ramp (40) is adjacent to the load bearing portion (20) of the cantilever portion (2) spanning the resection (92) of the lamina (91).   The implant set according to claim 19, wherein the reinforcing implant is the reinforcing implant according to any one of claims 1 to 18.

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