Vertebral implants for dynamic stabilization

Abstract

An intervertebral implant for stabilizing adjacent first and second interspinous processes. The implant includes a spacer having a latch housing wall extending from a first face to a second face, thereby defining the latch housing within the spacer. The spacer also has first and second sides, each configured to engage with one of the first and second adjacent interspinous processes. The spacer may define a plurality of slots configured to receive each portion of a flexible strap for wrapping around the first and second adjacent interspinous processes. The latch may be configured to rotate within the latch housing about a latch axis between first and second rotational positions.

Description

Technical Field

[0001] The disclosure of the present invention relates to the field of implants used in spinal surgery, and more particularly to vertebral implants for stabilizing adjacent first and second interspinous processes.

Background Art

[0002] Surgeries in the field of spinal surgery may involve the cervical (neck) region, the dorsal spine region, or more frequently the lumbar spine region.

[0003] When there is instability such as slippage of vertebrae relative to adjacent vertebrae, spinal stabilization devices may be used. Such spinal stabilization devices may include an intervertebral implant composed of a stabilization spacer, a flexible fabric strap-type strap, a movable assembly, and a locking member. The stabilization spacer is intended to be placed between two consecutive, i.e., adjacent, spinous processes of the vertebrae to be stabilized. The flexible strap (e.g., fabric strap) wraps around the spinous process. The movable assembly is adapted to engage the stabilization spacer to lock the flexible strap in a fixed position relative to the stabilization spacer. This is achieved by tightening the flexible strap between the movable assembly and the stabilization spacer. The locking member (e.g., a screw) is adapted to lock the engagement of the movable assembly with the stabilization spacer, thereby effecting final locking of the flexible strap.

[0004] An example of such an implant can be found, for instance, in EP 1009311 B1. In the EP 1009311 device, a flexible strap is fitted to the spacer, forming a loop. The flexible strap is locked by a quarter-swivel rotary latch that can be operated inside the spacer. However, this device does not guarantee the correct locking of the flexible strap, in particular when the flexible link is a flat strap over which the rotary latch can slide and swivel, as this does not guarantee the positioning of the rotary latch to its locked position.

[0005] Another example of an intervertebral implant is described in FR 3047657 A1 in the name of the present applicant. This device describes an implant comprising a stabilization spacer which is configured to stabilize at least two adjacent vertebrae by fixing them between the spinous processes of the vertebrae. The spacer comprises a recess having a longitudinal axis, the recess comprising a recess that radially receives at least one portion of a flexible strap on at least one side of the recess. The flexible strap secures the stabilization spacer to the spinous process of the vertebrae to be stabilized. The implant comprises a longitudinal axis and a locking pin having a profile substantially complementary to the shape of the recess. The locking pin is configured to be displaced in the direction of the longitudinal axis inside the recess and to lock the strap by tightening the latter between the locking pin and the inner wall of the recess. The device also further comprises a locking screw coaxial with the locking pin. The locking screw must be inserted into the recess after the flexible strap has already been positioned. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] EP 1009311 B1 [Patent Document 2] FR 3047657 A1 [Overview of the Initiative] [Means for solving the problem]

[0007] The following is a brief overview of the subject matter to provide a basic understanding of some aspects of it. This overview is not a comprehensive summary of the subject matter. It is not intended to identify the main or important elements of the subject matter, nor to define its scope. Its sole purpose is to present some of the concepts of the subject matter in a simplified form as an introduction to the more detailed explanation that will follow.

[0008] Exemplary embodiments of the disclosure of the present invention provide an intervertebral implant for stabilizing adjacent first and second interspinous processes. The implant may include a spacer having a first surface opposite to a second surface, the spacer having a latch housing wall extending from the first surface toward the second surface to define a latch housing within the spacer. The spacer may have a first side opposite to a second side, each of the first and second sides configured to engage with one of each of the first and second adjacent interspinous processes. The spacer may also define first, second, and third slots, each extending through the spacer from the first side to the second side. Each of the first, second, and third slots may be configured to receive portions of a flexible strap for wrapping around the first and second adjacent interspinous processes. The implant may further include a latch fixed within a latch housing and configured to rotate within the latch housing between first and second rotational positions, the latch having first and second faces, each positioned at different distances from the axis. When the latch is in the first rotational position, the first face of the latch can face the latch housing wall at a distance greater than the thickness of the strap, so that the flexible strap can move freely between the first face of the latch and the latch housing wall. When the latch is in the second rotational position, the second face of the latch can face the latch housing wall at a distance less than the thickness of the strap, so that the flexible strap is restricted from moving alongside and between the second face of the latch and the latch housing wall.

[0009] In some embodiments, the latch may include a head at a first end that defines a tool receiving opening configured to be engaged by a tool to rotate the latch between its first and second rotational positions. The head of the latch may include a head surface in which at least one notch is defined. The implant may also further include a locking mechanism maintained within a spacer. The locking mechanism may be movable within the spacer so as to engage with the head surface without entering the notch when the latch is in the first rotational position, and so as to enter the notch to prevent the latch from rotating further when the latch is in the second rotational position.

[0010] In some embodiments, the locking mechanism may be a spring rod fixed at one end in a spacer, with the other end of the spring rod movable in a notch. Advantageously, the locking mechanism may include two spring rods positioned on either side of the latch housing. The latch head may include a plurality of notches defined around its circumference, so that the spring rod can move into any one of the plurality of notches to lock the latch against the latch housing in a plurality of different rotational positions. The latch may include a ferrule at the end opposite the head that holds the latch within the latch housing.

[0011] In some embodiments, the first surface of the latch may be flat. The latch may include two such flat first latch surfaces positioned on either side of the latch relative to each other, and the two flat latch surfaces are at the first latch surface distance from each other. In addition, the first and second slots may be spaced apart by a slot distance from each other, and the first and second slots may intersect the latch housing, and the first latch surface distance may be less than or equal to the first slot distance so that the flexible strap can move freely across both of the flat first latch surfaces. In embodiments, both the second surface of the latch and the latch wall may be curved so as to be complementary to each other.

[0012] Another exemplary embodiment of the disclosure of the present invention provides an intervertebral implant for stabilizing adjacent first and second interspinous processes. The implant may include a spacer having a first side opposite to a second side, each of which is configured to engage with one of the respective first and second adjacent interspinous processes. The spacer may have first and second faces that are opposite to each other and perpendicular to the first and second sides, and the spacer may have a latch housing wall extending from the first face to the second face to define a latch housing within the spacer. The spacer may also define at least one slot extending through the spacer from the first side to the second side. At least one slot may intersect with the latch housing, and at least one slot may be configured to receive a portion of a flexible strap for wrapping around one or both of the first and second adjacent interspinous processes. The implant may also include a latch positioned within a latch housing, configured to rotate around a latch axis between a first rotational position in which the strap is free to move between the latch and the latch housing wall and a second rotational position in which the strap is restricted from moving between the latch and the latch housing wall. The latch may also include a locking mechanism maintained within a spacer and configured to selectively engage with the latch to prevent the latch from rotating within the latch housing when the latch is in the second rotational position.

[0013] In some embodiments, the latch may have a head that defines a notch adjacent to a first surface of the spacer. The locking mechanism may be a spring rod fixed at one end within the spacer, with the other end of the spring rod movable into the notch. The spacer may define a channel in which the spring rod resides. When the latch is rotated to a position where the notch aligns with the channel, at least a portion of the spring rod may move out of the channel into the notch to prevent the latch from rotating further within the latch housing.

[0014] In some embodiments, the locking mechanism may include two such spring rods positioned on either side of the latch housing. The latch head may include a plurality of notches defined around its circumference, so that the spring rods can move into any one of the plurality of notches to lock the latch into a plurality of different rotational positions relative to the latch housing.

[0015] In some embodiments, the latch may have first and second surfaces, each positioned at different distances from the axis. That is, when the latch is in a first rotational position, the strap can move freely between the first surface of the latch and the latch housing wall, since the first surface of the latch faces the latch housing wall at a distance greater than the thickness of the flexible strap. In addition, when the latch is in a second rotational position, the strap may be restricted from moving between the second surface of the latch and the latch housing wall, since the second surface of the latch faces the latch housing wall at a distance less than the thickness of the flexible strap.

[0016] In some embodiments, at least one slot may include two such slots, and the flexible strap has a first portion extending through one slot and a second portion extending through the other slot. Both portions of the flexible strap extending through the two slots may be configured to restrict movement between the second face of the latch and the latch housing wall. In addition, a spacer may also define a third slot, and the third portion of the flexible strap extends through the third slot. The flexible strap may form a first loop around a first adjacent interspinous process between the second and third slots, and the flexible strap may also form a second loop around a second adjacent interspinous process between the third and first slots.

[0017] According to some embodiments, the latch can include a tool receiving aperture configured to be engaged by a tool to rotate the latch between its first and second rotational positions. The latch can also include a ferrule at an end opposite the head for maintaining the latch within the latch housing. In an embodiment, the first face of the latch may be flat. In addition or alternatively, both the second face of the latch and the latch wall can be curved.

[0018] Still other features, details, and advantages will become apparent from the following detailed description and from the analysis of the accompanying drawings.

Brief Description of the Drawings

[0019] [Figure 1A] Exploded perspective view of an implant according to various embodiments of the disclosure of the present invention. [Figure 1B] Front view of the implant of FIG. 1A in the locked position. [Figure 1C] Front view of the implant of FIG. 1A in the unlocked position. [Figure 2] Side view of the implant of FIG. 1A. [Figure 3] Cross-sectional side view of the implant of FIG. 1A in the unlocked position. [Figure 4] Cross-sectional side view of the implant of FIG. 1A in the locked position. [Figure 5] Cross-sectional front view of the implant of FIG. 1A in the released position. [Figure 6] Cross-sectional front view of the implant of FIG. 1A in the locked position.

Modes for Carrying Out the Invention

[0020] Reference will now be made in detail to the specific embodiments shown in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding. However, it will be apparent to one of ordinary skill in the art that the embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, and / or components have not been described in detail so as not to obscure aspects of the embodiments.

[0021] Referring initially to FIG. 1A, this shows a vertebral implant 5 for dynamic vertebral stabilization and more particularly for stabilizing adjacent first and second interspinous processes (not shown in FIG. 1A but shown in FIG. 1B). According to this embodiment, the implant 5 includes a spacer 10, a rotary latch 20, and a strap 50 (shown in dashed lines). In some embodiments, the spacer 10 can be formed from a biocompatible polymer such as PEEK, and the latch 20 can be formed from stainless steel or titanium.

[0022] The spacer 10 includes a first face 11 that faces a second face 12 (shown most clearly, for example, in FIG. 2). In addition to this, the spacer 10 has a latch housing wall 16 (also shown, for example, in FIG. 5) that extends from the first face 11 towards the second face 12 so as to define a latch housing 15 within the spacer 10. The latch housing 15 can have various shapes, but is shown in the accompanying drawings as having a generally cylindrical bore shape.

[0023] The spacer 10 also has a first side 10a facing a second side 10b (as most clearly shown, for example, in Figure 1B). Referring to Figure 1B, each of the first and second sides 10a, 10b is configured to engage with one of the first and second adjacent interspinous processes (each schematically illustrated by dotted lines as 70a, 70b). More specifically, in the orientation shown in Figure 1B (showing the spacer 10 in the orientation it is thought to take when implanted in the body of a patient in an upright position), the first side 10a has a recess 101 configured to receive the lower edge of the upper of the adjacent interspinous processes 70a, while the second side 10b has a recess 102 configured to receive the upper edge of the lower of the adjacent interspinous processes 70b.

[0024] The spacer 10 also has one or more slots therein. For example, in the embodiments shown in all figures, the spacer 10 has a first slot 13, a second slot 14, and a third slot 19. Each of the three slots 13, 14, and 19 extends from the first side 10a through the spacer 10 to the second side 10b. In addition, in the illustrated embodiments, each of the first, second, and third slots 13, 14, and 19 is configured to receive each portion of a flexible strap 50 for engaging with the first and second adjacent interspinous processes, for example, by wrapping around them, as will be described in more detail below.

[0025] Continuing to refer to Figure 1A, the implant 5 includes a latch 20. The latch 20 is fixed within the latch housing 15 (as will be described in more detail below) and is configured to rotate about the latch axis Z. The latch 15 is rotatable within the latch housing 20 between a first rotational position (shown in Figures 3 and 5, which will be described in more detail in relation to these figures) and a second rotational position (shown in Figures 4 and 6, which will be described in more detail in relation to these figures).

[0026] The latch 20 can have a variety of different shapes, but in the illustrated embodiment, it has a substantially blade-shaped configuration with multiple faces. For example, the latch may have four faces, including two opposing faces 21a, 21b having a first shape and two opposing faces 21c, 21d having a second shape. Advantageously, as will be shown and described in more detail below, the faces of the first and second shapes can be positioned at different distances from the longitudinal axis Z.

[0027] Referring briefly to Figure 5, we see the latch 20 in the first rotational position described above. As shown in Figure 5, in this first rotational position, the latch 20 is positioned such that each of the first surfaces 21a and 21b of the latch 20 faces the respective curved regions 16a and 16b of the latch housing wall 16. The first surfaces 21a and 21b of the latch 20 are shown to be flat. In addition, in this first rotational position, each of the first surfaces 21a and 21b of the latch 20 is at a distance greater than the thickness of the flexible strap 50 (the strap 50 is not shown in Figure 5, but is shown, for example, in Figures 1A to 1C) (from the respective curved regions 16a and 16b of the latch housing wall 16). In this way, in this first rotational position of the latch 20, there is sufficient clearance between the first surfaces 21a, 21b of the latch 20 and the respective curved regions 16a, 16b of the latch housing wall 16, so that the strap 50 can move between the first surfaces 21a, 21b of the latch 20 and the respective curved regions 16a, 16b of the latch housing wall 16.

[0028] Referring briefly to Figure 6, we see the latch 20 in the second rotational position described above. As shown in Figure 6, in this second rotational position, the latch 20 is positioned such that each of the second surfaces 21c, 21d of the latch 20 faces the respective curved regions 16a, 16b of the latch housing wall 16. The second surfaces 21c, 21d of the latch may be curved (for example, complementary to the curved regions 16a, 16b of the latch housing 16), or they may be triangular or corrugated depending on the required holding strength, for example. In addition, in this second rotational position, each of the second surfaces 21a, 21b of the latch 20 is at a distance (from the respective curved regions 16a, 16b of the latch housing wall 16) less than the thickness of the flexible strap 50 (again, the strap 50 is not shown in Figure 5, but for example, it is shown in Figures 1A to 1C). In this way, at this second rotational position of the latch 20, the strap 50 does not have sufficient clearance between the second surfaces 21c, 21d of the latch 20 and the respective curved regions 16a, 16b of the latch housing wall 16, and as a result, the strap 50 is restricted from moving alongside and between the second surfaces 21c, 21d of the latch 20 and the respective curved regions 16a, 16b of the latch housing wall 16.

[0029] Referring again to Figure 1A, the latch 20 may include a head 23 at its first end that sets a tool receiving opening 24 in its face. The tool receiving opening 24 is configured to be engaged by a tool (not shown, but may be a rotary tool such as a star hexagon, hexagon, or other screwdriver) to rotate the latch 20, for example, to rotate the latch 20 between the first and second rotation positions described above. Advantageously, and as shown for example in Figure 2, only the uppermost portion of the head 23 can protrude slightly from the first face 11 of the spacer 10, thereby providing it with a very low profile.

[0030] Referring again to Figure 1A, the head 23 of the latch 20 may include sides around the sides of the head 23, which are substantially perpendicular to the face of the head 23 that defines the tool receiving opening 24. The sides of the head 23 may include one or more flat surfaces 28 (as most clearly shown in Figures 1A and 1B). In addition, the sides of the head 23 may include at least one notch 25 defined therein. The sides of the head 23 may include any number of notches 25, but in the embodiments shown in Figures 1A and 1B, two notches 25 are defined, located on opposite sides of the head 23.

[0031] The implant 5 may also include a locking mechanism maintained within the spacer 10. Referring to Figure 1A, it will be recognized that in the illustrated embodiment the locking mechanism includes one pair of spring rods 30, but in other embodiments one or more spring rods 30 may be provided. In embodiments, the spring rods 30 may be formed from stainless steel or titanium. The spring rods 30 may reside in a tubular notch or channel 18 that extends substantially parallel to the axis Z and is adjacent to and in communication with the latch housing 15. In addition, the spring rods 30 are movable within the spacer 10 to engage with the side of the head 23, for example, a flat surface 28, without entering the notch 25 when the latch 20 is in the first rotational position described above. In addition, the spring rod 30 may be further movable within the spacer 10 so as to enter the notch 25 of the head 23 when the latch 20 is in the second rotational position described above, thereby preventing yet another rotation of the latch 20 and thereby increasing the locking force applied to the strap 50 within the spacer 20. The notch 18 defines a restraining end 18b (most clearly shown in Figures 5 and 6) into which one end of the spring rod 30 is inserted, thereby restricting the movement of this end of the spring rod 30. The notch 18 also defines open ends 18a (most clearly shown in Figure 1A) at both ends of the notch 18 (the ends of the notch 18 positioned adjacent to the head 23 of the latch 20), which allow the spring rod 30 to bend freely within the latch housing 16 and into the notch 25 of the head 23.

[0032] As also shown in Figure 1A, the latch 20 may also include a stud 26 positioned on its second end, for example, the end of the latch opposite the end having the head 23. The spacer 10 may also have a latch locking mechanism, such as a ferrule 40, which engages with the stud 26 to prevent the latch 20 from exiting the latch housing 16. Additional details of such arrangements are shown and described with respect to them, for example, in Figures 3 and 4.

[0033] Referring to Figure 1B, details of the addition of the flexible strap 50 according to various embodiments are shown. As listed above, the spacer 20 may have at least one slot extending through the spacer 20 from the first side 10a to the second side 10b. In the embodiment shown in Figure 1B, the spacer 10 has a first slot 13, a second slot 14, and a third slot 19, each of the first, second, and third slots 13, 14, and 19 extending through the spacer 10 from the first side 10a to the second side 10b, and each of the first, second, and third slots 13, 14, and 19 is configured to receive each portion of the flexible strap 50 for engaging with the first and second adjacent interspinous processes, for example, by wrapping around them. More specifically, Figure 1B shows an embodiment in which the strap 50 has a folded end 54 located on the second side 10b of the spacer 10, the folded end 54 being larger than the opening of the second slot 14 so as to prevent it from being pulled through the second slot 14. The strap 50 then exits the second slot 14 on the first side 10a of the spacer 10 and finally enters the third slot 19 on the first side 10a of the spacer 10. The portion of the strap 50 between the second slot 14 and the third slot 19 on the first side 10a of the spacer 10 can form a first loop 51 of the strap 50, configured to loop around a first of the adjacent interspinous projections, for example, the upper one in the illustrated orientation.

[0034] Continuing to refer to the embodiment in Figure 1B, the strap 50 then exits the third slot 14 on the second side 10b of the spacer 10 and finally enters the first slot 13 on the second side 10b of the spacer 10. The portion of the strap 50 between the third slot 19 on the second side 10b of the spacer 10 and the first slot 19 on the second side 10b of the spacer 10 can form a second loop 52 of the strap 50, configured to loop around a second of the adjacent interspinous processes, for example, the lower one in the illustrated orientation. Furthermore, the strap 50 can then exit the first slot 13 on the first side 10a of the spacer 10 to provide a free end 53 of the strap, ensuring that the strap 50 has sufficient length to accommodate patients of different sizes.

[0035] Naturally, it must be recognized that the strap 50 of the implant 5 may have other configurations. For example, the portion of the strap 50 that includes a free end 54 and extends through the second slot 14 can be eliminated in other embodiments, for example, by eliminating the second slot 14 and instead attaching the strap 50 directly to the first side 10a of the spacer 10. Furthermore, in another embodiment, a configuration is envisioned that has only a single loop and a single slot of the strap (therefore looping around only one of the two adjacent interspinous processes, rather than both). In this such embodiment, the second loop 52 of the strap 50 can be attached directly to the second side 10b of the spacer 10 in the vicinity of where the strap 50 exits the third slot 19 in Figure 1B, thereby eliminating the third slot 19 as well. In such an embodiment, the strap 50 is thought to extend from the first connection point on the second side 10b of the spacer 10 through the first slot 13 so as to form only a second loop 52, the second loop 52 looping around the lower of the two adjacent interspinous processes (in the orientation shown in Figure 1B). Such a single-loop embodiment is thought to still be able to provide some degree of vertebral stabilization to the two adjacent interspinous processes, since the spacer is thought to prevent the two adjacent interspinous processes from being compressed relative to each other, while still allowing them to expand relative to each other.

[0036] As listed above, Figure 3 shows implant 5 in a cross-section along plane AA of Figure 1B, and latch 20 is in the first rotational position described above, for example, a position in which strap 50 (not shown in Figure 3) is movable within spacer 10. As shown in Figure 3, in this first rotational position described above, latch 20 is oriented around the longitudinal axis Z such that the flat surfaces 21c, 21d are parallel to the first and second slots 13, 14 that pass through and intersect with the latch housing 15. In this embodiment, the width of latch 20 between the flat surfaces 21c and 21d is less than or equal to the distance between the first and second slots 13, 14, thereby allowing the strap to freely pass through the slots and enter the housing 15. Yet another viewpoint of these components in this first rotational position described above is shown, for example, in Figure 5, illustrating a cross-sectional view of the implant taken along plane BB of Figure 2.

[0037] Referring to Figure 4, implant 5 is again shown in a cross-section along plane AA of Figure 1B, and the latch 20 is in the rotational position where the second, for example, strap of the latch 20 is locked. In this position, the latch 20 is oriented around the longitudinal axis Z such that the flat surfaces 21a, 21b of the latch 20 are now approximately perpendicular to the first and second slots 13, 14, and the curved surfaces 21c, 21d of the latch 20 face directly to the curved surfaces 16a, 16b of the latch housing 16. As listed above, the distance between the curved surfaces 21c, 21d of the latch 20 and the curved surfaces 16a, 16b of the latch housing 16 is smaller than the thickness of the strap 50 so that the strap 50 is caught between the curved surfaces 21c, 21d of the latch 20 and the curved surfaces 16a, 16b of the latch housing 16. In this embodiment, the distance between the curved surfaces 21c, 21d of the latch 20 and the curved surfaces 16a, 16b of the latch housing 16 can be 0.8 to 0.9 times the thickness of the strap 50. Yet another viewpoint of these components in this second rotational position described above is shown, for example, in Figure 6, which also illustrates the cross-section of the implant in the plane BB of Figure 2.

[0038] Returning to Figures 3 and 4, the latch housing 16 of the spacer 10 has a bottom 17 that defines a lower surface 17b. The foot 27 of the latch 20 is positioned against the bottom surface 17b to prevent the latch from moving too far downward (in the view of Figures 3 and 4). In addition, the bottom 17 of the latch housing 16 defines a counterbore having a shoulder that defines the lower surface 17b against which the flange 41 of the ferrule 40 rests when the ferrule 40 is fixed on the stud 26 of the latch 20 (e.g., by crimping, gluing, or other means of connection). Advantageously, and as shown, the ferrule 40 does not protrude beyond the second surface 12 of the spacer 20 in order to maintain a thin profile. In this way, the ferrule 40 forms a means for holding the latch 20 in the spacer 10, thereby allowing the spacer 10 with the latch 20 pre-installed to be implanted in the patient.

[0039] Figures 1A to 6 show embodiments in which the latch housing 16 has a substantially cylindrical bore configuration (with the latch 20 having a complementary configuration), but it should be noted that additional exemplary embodiments are conceivable in which the latch housing 20 may have a substantially conical configuration (for example, the cross-section tapering along the Z-axis from the head 23 to the foot 27 of the latch), while the latch 20 may have, for example, second faces 21c, 21d that complement such a substantially conical profile.

[0040] Furthermore, while the figure shows a single implant 5 used in conjunction with a pair of adjacent vertebrae 70a, 70b, it is understood that more than one implant 5 may be used at different levels of the spine to stabilize a pair of adjacent vertebrae. For example, a system or kit containing implants 5 of different sizes can be provided so that different regions of the spine can be stabilized using implants 5 of the appropriate size.

[0041] There are no limitations on the specific embodiments described herein, and these embodiments are intended merely to be illustrative of various aspects. As will be apparent to those skilled in the art, many modifications and changes can be made without departing from the spirit and scope of this application. Functionally equivalent methods and apparatus, in addition to those listed herein, will be apparent to those skilled in the art from the foregoing description. Such modifications and changes are intended to be contained within the appended claims. Only the provisions of the appended claims are intended to be limiting, along with the entire scope of equivalents for which such claims are entitled. It will also be understood that the terminology used herein, such as “and,” “or,” “including,” “at least,” and the use of plural or singular forms, is for illustrative purposes only and is not intended to be limiting. [Explanation of Symbols]

[0042] 5 Vertebral implants 10 Spacers 24 tool acceptance openings 30 Spring Rod 40 ferrules

Claims

1. An intervertebral implant for stabilizing adjacent first and second interspinous processes, A spacer having a first surface facing a second surface, wherein the spacer has a latch housing wall extending from the first surface toward the second surface so as to define a latch housing within the spacer, The spacer has a first side facing a second side, and each of the first and second sides is configured to engage with one of the first and second adjacent interspinous processes, The spacer also defines first, second, and third slots, each extending through the spacer from the first side to the second side, and each of the first, second, and third slots is configured to receive portions of a flexible strap for wrapping around the first and second adjacent interspinous processes. The aforementioned spacer, A latch fixed within the latch housing and configured to rotate around a latch axis between first and second rotational positions within the latch housing, the latch having first and second faces each positioned at different distances from the axis, Includes, When the latch is in the first rotational position, the first surface of the latch faces the latch housing wall at a distance greater than the thickness of the flexible strap, thereby allowing the strap to move freely between the first surface of the latch and the latch housing wall. When the latch is in the second rotational position, the second surface of the latch faces the latch housing wall at a distance from the latch housing wall less than the thickness of the flexible strap, thereby restricting the strap from moving alongside and between the second surface of the latch and the latch housing wall. Intervertebral implants.

2. The implant according to claim 1, wherein the latch includes a head at its first end that defines a tool receiving opening, and the tool receiving opening is configured to be engaged by a tool to rotate the latch between its first and second rotational positions.

3. The implant according to claim 1, wherein the head of the latch includes a head surface having at least one notch therein.

4. A locking mechanism maintained within the spacer, wherein the locking mechanism engages with the head surface without entering the notch when the latch is in the first rotational position, and the locking mechanism enters the notch to prevent the latch from rotating further when the latch is in the second rotational position, the locking mechanism is movable within the spacer. The implant according to claim 3, further comprising:

5. The implant according to claim 4, wherein the locking mechanism is a spring rod fixed at one end within the spacer, and the other end of the spring rod is movable within the notch.

6. The implant according to claim 5, wherein the locking mechanism includes two spring rods positioned on both sides of the latch housing.

7. The implant according to claim 6, wherein the latch head includes a plurality of notches defined around its circumference, thereby allowing the spring rod to move into any one of the plurality of notches to lock the latch against the latch housing at a plurality of different rotational positions.

8. The implant according to claim 1, wherein the latch includes a ferrule at the end opposite the head for maintaining the latch within the latch housing.

9. The implant according to claim 1, wherein the first surface of the latch is flat.

10. The implant according to claim 9, wherein the latch includes two flat first latch surfaces arranged relative to each other on both sides of the latch, and the two flat latch surfaces are at a first latch surface distance from each other.

11. The first and second slots are spaced apart from each other by a slot distance. The first and second slots intersect with the latch housing, The first latch surface distance is less than or equal to the first slot distance so that the flexible strap can move freely across both of the flat first latch surfaces. The implant according to claim 10.

12. The implant according to claim 1, wherein both the second surface of the latch and the latch wall are curved to be complementary to each other.

13. An intervertebral implant for stabilizing adjacent first and second interspinous processes, A spacer having a second side and a first side opposite to it, wherein each of the first and second sides is configured to engage with one of the first and second adjacent interspinous processes, The spacer has first and second surfaces that face each other and are perpendicular to the first and second sides, and the spacer has a latch housing wall extending from the first surface toward the second surface so as to define the latch housing within the spacer. The spacer defines at least one slot extending through the spacer from the first side to the second side, the at least one slot intersecting the latch housing, and the at least one slot is configured to receive a portion of a flexible strap for wrapping around one or both of the first and second adjacent interspinous processes. The aforementioned spacer, A latch positioned within the latch housing, wherein the latch is configured to rotate around its axis between a first rotational position in which the strap moves freely between the first face of the latch and the wall of the latch housing, and a second rotational position in which the strap is restricted from moving between the second face of the latch and the wall of the latch housing, A locking mechanism maintained within the spacer, configured to selectively engage with the latch to prevent the latch from rotating within the latch housing when the latch is in the second rotational position, Intervertebral implants, including those included.

14. The implant according to claim 13, wherein the latch has a head adjacent to the first surface of the spacer, and the head defines a notch.

15. The implant according to claim 14, wherein the locking mechanism is a spring rod fixed at one end within the spacer, and the other end of the spring rod is movable within the notch.

16. The spacer defines the channel in which the spring rod exists. When the latch is rotated to a position where the notch is aligned with the channel, at least a portion of the spring rod moves out of the channel into the notch to prevent the latch from rotating further within the latch housing. The implant according to claim 15.

17. The implant according to claim 16, wherein the locking mechanism includes two spring rods positioned on both sides of the latch housing.

18. The implant according to claim 17, wherein the latch head includes a plurality of notches defined around its circumference, thereby allowing the spring rod to move into any one of the plurality of notches to lock the latch against the latch housing at a plurality of different rotational positions.

19. The latch has first and second surfaces, each positioned at different distances from the axis, When the latch is in the first rotational position, the first surface of the latch faces the latch housing wall at a distance greater than the thickness of the flexible strap, so that the strap can move freely between the first surface of the latch and the latch housing wall. Furthermore, when the latch is in the second rotational position, the second surface of the latch faces the latch housing wall at a distance from the latch housing wall that is less than the thickness of the flexible strap, so that the strap is restricted from moving between the second surface of the latch and the latch housing wall. The implant according to claim 13.

20. The at least one slot comprises two slots, and the flexible strap has a first portion extending through one slot and a second portion extending through the other slot. Both portions of the flexible strap extending through the two slots are configured to be restricted from moving between the second surface of the latch and the latch housing wall. The implant according to claim 13.

21. The implant according to claim 20, wherein the spacer further defines a third slot, a third portion of the flexible strap extends through the third slot, the flexible strap forms a first loop around the first adjacent interspinous process between the second and third slots, and the flexible strap also forms a second loop around the second adjacent interspinous process between the third and first slots.

22. The implant according to claim 13, wherein the latch includes a tool receiving opening, and the tool receiving opening is configured to be engaged by a tool so as to rotate the latch between its first and second rotational positions.

23. The implant according to claim 14, wherein the latch includes a ferrule at the end opposite the head for maintaining the latch within the latch housing.

24. The implant according to claim 19, wherein the first surface of the latch is flat.

25. The implant according to claim 19, wherein both the second surface of the latch and the latch wall are curved.

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