KR20060056265A - Controlled artificial intervertebral disc implant - Google Patents

Abstract

The invention relates to an artificial intervertebral disc for placement between adjacent vertebrae. The artificial intervertebral disc is preferably designed to restore disc height and natural disc curvature, allow for a natural range of motion, absorb shock and provide resistance to motion and axial compression. Furthermore, the intervertebral disc may be used in the cervical, the thoracic, or the lumbar regions of the spine. The artificial intervertebral disc may include either singularly or in combination: an interior including at least one spring member preferably incorporating a arcuate surface member, a flexible core, the flexible core preferably being a slotted core, a ring spring, a winged leaf spring, or a leaf spring, or. The articulating member preferably being attached to one of the endplate by an intermediate shock absorbing element.

Description

CONTROLLED ARTIFICIAL INTERVERTEBRAL DISC IMPLANT}

The present invention relates to apparatus and methods for the treatment of trauma and disease of the spine. More specifically, the present invention relates to intervertebral disc substitutes.

Various conditions such as spondylolysis, disc herniation, compression of spinal nerve roots, degenerative disc disease and trauma are known to cause extreme discomfort that requires medical attention. Among the procedures currently used to alleviate this condition are spinal fusion, such as intervertebral and posterior fusion or arthroplasty. In these procedures, two adjacent vertebral bodies are fused together. The damaged intervertebral discs are first excised and an implant is inserted that accommodates bone growth between the two vertebral bodies to effectively bridge the gap left by disk removal. Numerous different implant materials and implant designs have been used for fusion with varying success rates. Although intervertebral and posterior fusion are widely used, disadvantages of its use include reduced physiological range of motion and other fusion related complications such as degeneration of adjacent discs and instability of functional spinal units. As a result, alternative treatments with less complications but with similar fusion efficiencies are needed. One such alternative to spinal fusion is the use of arthroplasty and prosthetic or artificial discs.

In general, arthroplasty is used to replace diseased joints. Because arthroplasty tends to be performed after fusion, it involves a series of procedures aimed at maintaining the motion of the joint, thereby preserving its integrity and preventing deteriorating adjacent motor segments. Depending on the condition and location of the diseased joint, certain arthroplasty procedures can be used. As an example, interpositional reconstruction surgery, which reshapes joints and adds prostheses between the two bones that form the joints, is commonly used for elbow, shoulder, ankle and finger joints. Total joint replacement or total arthroplasty replaces entire diseased joints with prosthetic prostheses, and has recently become the surgery of choice for most knee and hip problems.

Buttock and knee replacements are particularly widespread, with nearly 300,000 hip replacements and nearly equal knee replacements performed in the United States in 2001. With regard to knee and hip replacement surgery, there are a number of available implants or prostheses. For buttock prostheses, in an exemplary design, there are two components, one is a metal ball attached to a metal stem that fits into the femur, and the second is a mating plastic socket implanted in the pelvis. The metal member is generally formed of stainless steel, an alloy of cobalt and chromium, an alloy of titanium and titanium, and the plastic member is generally formed of high density polyethylene. For knee prostheses, in exemplary embodiments, metal and plastic components are used to replace damaged bone ends and cartilage again. Metal members are generally formed of stainless steel, alloys of cobalt and chromium, alloys of titanium and titanium, and plastic members are generally formed of high density polyethylene.

Although advances in spinal arthroplasty and prosthetic use in the spine are similar to those in other joints in the body that have developed from joint fusion to replacement of functional joints, however, the emergence of spinal arthroplasty is slower than arthroplasty of other major joints in the body. Some of the possible reasons why vertebral arthroplasty has been delayed are that spinal problems related to disc degeneration are difficult to diagnose, spinal procedures are usually seizure-induced, and conservative solutions such as fusion are acceptable and spinal anatomy Is complicated.

Over the last 40 years, spinal arthroplasty technology has evolved, and in recent decades, spinal arthroplasty has attracted the attention of leading physicians and implant manufacturers. The development of spinal arthroplasty actually began in the 1950s, and one of several emerging concepts was the spherical concept of disc prosthetics. The spherical concept is a simple placement of the ball in a substantially circumferential direction within the cavity of the nucleus pulposus after the spinal discectomy procedure is performed. The ring is held in place and the ball functions as a nuclear replacement. Various materials have been tested for spherical concepts. For example, in the early 1960s, implants using silicon ball bearings were implanted in the cervical region of the patient, but the outcome was uncertain. In the mid-1960s, stainless steel (ball bearing) prostheses were implanted in the patient. The result of the prosthesis was initially good, but over time, the disc space lost its height due to subsidence of the steel ball into the vertebral body. Currently, the concept of spherical prosthetics is constantly being tested using different materials, the most recent being modified carbon fiber.

Another emerging concept is mechanical concept design. The mechanical conceptual design is substantially a total disk replacement product aimed at restoring the range of motion of the spinal motion segment unit. These devices often consist of a metallic endplate secured to adjacent vertebral bodies via a stabilization mechanism and a core formed of polyethylene or other polymeric material. Alternatively, instead of the core, a bearing face is used and the bearing face material is ceramic-on-ceramic, metal-on-metal or metal-on-polyethylene. The mechanical design concept is based on the same principles as joint reconstruction products such as knee and buttock replacements, and various mechanical design prosthetic concepts have been proposed and continue to be proposed.

Another concept is the physiological concept. The physiological concept uses a hydrogel, elastomer or polyurethane based core, which aims to restore disk function by absorbing and releasing fluid between the end plates of the patient while also maintaining the disk's natural shock absorption or cushioning function. It is done. Physiological conceptual devices are generally considered only partial solutions because they are designed to replace the nucleus or part of the disc.

All approaches to disc replacements are aimed at some or all of the following. Alleviation of discotic pain, restoration of the range of motion, maintenance of the natural shock-absorbing function of the disc, restoration of normal shape or disc height and restoration of physiological kinematics. In general, four exemplary types of artificial intervertebral discs have been developed to replace some or all of the discs. Elastomer / Fluid Rechargeable Discs, Ball and Socket Discs, Mechanical Spring Discs and Hybrid Discs.

Elastomer / fluid-filled discs typically include an elastomer cushion or fluid filled chamber disposed between the lower and upper rigid end plates. The cushions and chambers of these implants function properly similar to the intervertebral disc tissue removed, in terms of mechanical behavior.

Ball and socket-shaped discs typically include two plate members having cooperative inner ball and socket portions to allow joint movement of the member during movement of the spine.

Mechanical spring discs typically include one or more coil springs disposed between the metal end plates. Coil springs define a cumulative spring constant designed to be sufficient to maintain a spaced arrangement of adjacent vertebrae while allowing normal movement of the spine during flexion and extension of the spine in a given direction.

Hybrid disks, the fourth type of artificial intervertebral disc, incorporate two or more of the design principles described above. By way of example, one known hybrid disk arrangement includes a ball and socket joint surrounded by an elastomer ring.

While each of the prostheses described above addresses some of the problems associated with intervertebral disc replacements, each implant presents a significant disadvantage. Thus, there is a need for intervertebral implants that accommodate the anatomy and geometry of the ends of adjacent vertebral bodies and the intervertebral space considered to be filled, while providing reliability and simplicity of design. In particular, it provides stability to support the high loads applied to the vertebrae, allows the patient sufficient mobility to allow a close range of normal movement, provides axial compression between adjacent vertebrae, and provides shock absorption. There is a need for vertebral disc implants.

The present invention relates to an intervertebral disc, which is preferably designed to restore disc height and forefoot only, enable a natural range of motion, absorb shocks, and provide resistance to movement and axial compression. In addition, the intervertebral disc may be used in the cervical, thoracic or lumbar region of the spine.

The intervertebral disc includes a body having a footprint that is preferably sized and shaped with at least a portion of the ends of adjacent vertebrae. The shape of the intervertebral disc includes, but is not limited to, round, ovoid, oval, kidney beans, annular, C-shaped, D-shaped, and the like.

In one embodiment, the body of the intervertebral disc includes an upper end plate, a lower end plate and an elastic membrane disposed between the upper and lower end plates. Alternatively, the elastic membrane can enclose or enclose the end plate. The elastic membrane is combined with the upper and lower end plates to form an interior volume. The inner space of the disk includes at least one spring element attached to the upper and lower end plates. Preferably, the spring element is attached to the lower end plate in a groove or pocket formed on the inner surface of the lower end plate, and the upper end of the spring element is attached to the hemispherical member. The hemispherical member is designed to articulate with a socket formed on the inner surface of the upper end plate.

Alternatively, the disk may be provided with a plurality of spring elements each extending from the upper end plate to the lower end plate, each spring element having hemispherical members at both ends to mate with corresponding sockets formed on the inner surfaces of the upper and lower end plates. can do. The disc may also be configured such that the disc generally comprises a first spring element surrounded by a plurality of second spring elements spaced evenly around the first spring element. The first spring element preferably has a stiffness and / or a spring constant that is greater than the stiffness of the peripheral spring element.

In addition, the disk may comprise a plurality of spring elements, with only a portion of the spring elements being attached to the hemispherical member and the rest of the spring elements being attached to the upper and lower end plates. In one exemplary embodiment, the first spring element is attached to the hemispherical member, and the surrounding circumferential second spring element is attached directly to the upper and lower end plates.

The disk may include elastomeric struts or rings in place of all or one spring element. The disc can also incorporate a casing member.

The disk includes a fluid disposed within the interior space and may also include a valve to allow removal and insertion of the fluid.

The upper and lower end plates are preferably formed of metals such as titanium, stainless steel, titanium alloys, cobalt-chromium alloys or amorphous alloys. Alternatively, however, the upper and lower end plates may be ceramics, composites, polymers such as poly-ether-ether-ketones (i.e.PEEK) or ultra high molecular weight polyethylene (i.e.UHMWPE), cortex, sponges, allografts, autografts, xenogenes. It may be formed of bone, including implanted, demineralized or partially demineralized bone, or any other material that can function as a load bearing support. The material selected for the endplate in combination with a good fluid is preferably selected to reduce the amount of wear and thus increase the life of the joint.

 The outer surfaces of the upper and lower end plates may be substantially flat, wedge shaped, or the like. In addition, the outer surfaces of the upper and lower end plates may be dome shaped with their radii formed in the sagittal and coronal planes substantially coincident with those of the ends of adjacent vertebrae. The dome shape allows the upper and lower end plates to better match the ends of adjacent vertebrae for better engagement in the field.

The intervertebral disc also includes a migration-stopping structure provided on the outer surface of at least one or both of the endplates to prevent movement, separation, or eviction of the endplates from within and within the adjacent vertebrae. The migration-stop structures may include flaps, spikes, teeth, fins, deployed spikes, deployed teeth, flexible spikes, flexible teeth, alternatively shaped teeth, insertion or extended wings, screws , Rings, teeth, ribs, and textured surfaces.

In addition, the upper and lower end plates are preferably coated with a bone growth agent that introduces or induces a substance for promoting bone ingrowth to permanently secure the disk to adjacent vertebrae. Alternatively, the upper and lower end plates may have a roughened surface, a porous surface, a laser treated end plate layer, include a bone conduction / oskeletal skeleton, or integrate bone conduction and / or osteoinduction to promote bone internal growth. It may have or consist of a material. The end plate may further comprise a member and / or barrier to limit the amount and / or depth of bone ingrowth.

The upper and lower end plates may also have implant device attachment, guide and retention structures. By way of example, the endplate may have holes, slots, threads or dovetails for implanting and / or distracting adjacent vertebrae. By way of example, the disk may include slots formed in the upper and / or lower end plates, which slots are formed to receive the implant insertion mechanism, the distractor or both.

The upper and lower end plates also include articulation surfaces, and therefore it is desirable to provide intervertebral discs with greater mobility. In order to minimize wear, reduce particulate production, and increase disk life, the joint surface preferably includes similar wear reduction finishes such as surface polishing, diamond finishes, TiNi finishes, and the like.

In some embodiments, the interior of the disc may include a leaf spring having one end attached to the upper and / or lower end and the other end unattached. The leaf spring includes an enlarged convex intermediate section disposed between both ends and preferably mating, articulating, and sliding with the inner surface of one of the end plates. Preferably, the unattached end of the leaf spring is attached to the roller by an axle, which causes the roller to rotate freely so that the leaf spring freely moves when the spring contracts.

In some embodiments, the interior space of the disc includes articulation members attached to the upper or lower endplate. The articulation member is preferably attached to one of the end plates by an intermediate buffer layer. The buffer layer is preferably elastomeric, polymeric fibers, polyurethane, silicone, or other suitable elastic material having cushioning properties.

In another embodiment, the disc generally comprises an upper end plate, a lower end plate and a flexible core disposed in a pocket, preferably comprising a mating surface, disposed between the upper and lower end plates. The flexible core is preferably a slotted core, ring spring, vane leaf spring or leaf spring. The flexible member may be configured to provide dimensions to provide contraction / extension, lateral bending, axial rotation, and / or traslation depending on the load conditions applied to the intervertebral disc.

The intervertebral disc may be implanted modularly if possible, or may be preassembled and implanted. Translocation anterior or sited surgical approaches can be used to implant the intervertebral discs. In addition, depending on the intervertebral disc to be implanted, minimally invasive surgery or similar distraction and transplant surgery may be used. In addition, depending on the intervertebral disc to be implanted, the entire ligament may be attached directly to the disc or to the adjacent vertebral body. The total ligament may be formed as a demineralized or partially demineralized allograft, autograft, xenograft. Alternatively, the whole ligament may be formed from biocompatible materials such as elastomers or braided polymers. To assist with the implantation of the intervertebral disc, the intervertebral disc may include an alignment marker.

To illustrate the invention and to facilitate understanding of the invention, exemplary and preferred features and embodiments are set forth in the accompanying drawings, but the invention is not limited to the precise arrangements and instrumentalities illustrated, and throughout the drawings, similar It should be understood that reference signs indicate similar elements.

1 is a perspective view of a first embodiment of an artificial intervertebral disc according to the present invention.

2 is a cross-sectional view of the artificial intervertebral disc of FIG. 1 taken along line A-A.

2A is an alternative cross-sectional view of the artificial intervertebral disc of FIG. 1 taken along line A-A.

FIG. 2B is an alternative cross sectional view of the artificial intervertebral disc of FIG. 1 taken along line A-A. FIG.

2C is an alternative cross-sectional view of the artificial intervertebral disc of FIG. 1 taken along line A-A.

FIG. 2D is an alternative cross sectional view of the artificial intervertebral disc of FIG. 1 taken along line A-A. FIG.

3A is a side view of a deployed spike in accordance with the present invention.

3B is a side view of another deployed spike in accordance with the present invention.

3C is a cross-sectional view of the flexible spike in accordance with the present invention.

3D is a side view of an alternatively shaped tooth in accordance with the present invention.

3E is a side view of an anchor according to the present invention.

4 is a cross-sectional view of a second embodiment of an artificial intervertebral disc according to the present invention.

4A is a side view of the leaf spring and roller of the artificial intervertebral disc of FIG.

5 is a sectional view of a third embodiment of an artificial intervertebral disc according to the present invention.

6 is a perspective view of a fourth embodiment of an artificial intervertebral disc according to the present invention.

7 is a perspective view of a fifth embodiment of an artificial intervertebral disc according to the present invention.

8 is a perspective view of a sixth embodiment of an artificial intervertebral disc according to the present invention.

9 is a sectional view of a seventh embodiment of an artificial intervertebral disc according to the present invention.

9A is another cross-sectional view of the seventh embodiment of an artificial intervertebral disc according to the present invention.

9B is an exploded view of the seventh embodiment shown in FIG. 9A.

9C is an exploded view of the seventh embodiment shown in FIG. 9A.

10 is a schematic diagram of an eighth embodiment of an intervertebral disc according to the present invention.

Any widely different implant structure can be prepared according to the techniques shown by illustrative examples of the intervertebral discs disclosed herein. The intervertebral discs of the present invention are preferably designed to restore spinal lordosis and disc height, to allow a natural range of motion, shock absorption, and to provide resistance to movement and axial compression.

The intervertebral disc is preferably dimensioned and configured for use in the cervical, thoracic and lumbar regions of the spinal cord. In addition, intervertebral discs are made for each patient to allow for disc characteristics appropriate for the individual patient. By way of example, the core of the disc may comprise different assemblies, different components and / or various types of materials to create certain properties for each individual patient.

The intervertebral disc may also allow bending, extension, lateral flexion, rotation and translational movement. Bending is the motion that leads the joint or two parts of the body to the bend position, where in the spinal cord it is the motion that the spinal cord initiates straightening and moves to forward bending. An extension is a motion in which two parts are pulled apart from each other, and in the spinal cord, this is the motion in which the spinal cord begins to straighten and move to posterior flexion. Lateral flexion is a flexion movement toward the lateral side, and in the spinal cord this movement generally involves flexion (lateral) and coupled rotation. Rotation is a motion that causes twisting, rotation, or turning about the axis of the spine of a portion of the spinal cord. Translational motion is generally a limited motion transverse to the axis of the spine.

In addition, similar to the natural intervertebral disc, it is desirable that the artificial intervertebral disc allows for a rotational axis of movement. At every moment of the body in planar motion, there is a virtual distraction of the line or of this line which does not move in the body. The instant axis of rotation is this line. The moment of rotation axis of rotation refers to the ability of the momentary axis of rotation to move (ie, translational movement) as a result of different loading conditions, in other words the position of the momentary axis of rotation relative to the disc. The preferred mean position of the axis of rotation of the moment of rotation with respect to the lumbar region of the spinal cord is preferably at the proximal side of the posterior half or adjacent (upper or lower) endplates of disc space, preferably at the proximal side of the lower / rear endplates, The preferred average position of the moment of rotation axis relative to the thoracic region of is preferably at the lower part of the disc space and the proximal side of the trailing vertebral body extending posteriorly into the spinal canal, and the preferred mean position of the moment of rotation axis relative to the cervical region of the spinal cord is It is preferred to be in the posterior half of the trailing vertebral body.

Also similar to natural intervertebral discs, the response characteristics of artificial intervertebral discs are preferably nonlinear. As an example, in response to continuous axial compression, the artificial intervertebral disc preferably experiences a large initial compression amount followed by nonlinearly increasing the compression amount.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments and features of an artificial intervertebral disc are described in detail with reference to the accompanying drawings. However, it should be noted that these descriptions of specific embodiments and features are merely illustrative. One or more features or elements of the various embodiments may be combined or used alone, and it is contemplated that variations of the various embodiments, as well as other embodiments, may be contemplated and will be apparent to those skilled in the art.

Referring first to FIG. 1, there is shown a perspective view of a first exemplary embodiment of an artificial intervertebral disc 10. As shown, the disc 10 has a generally kidney bean-shaped footprint having a transverse side 11, a posterior side 13, and first and second lateral sides 15, 17, respectively. The distal side 11 and the lateral sides 15 and 17 are both substantially convex and the rear side 13 is substantially concave. However, the disk 10 may take other shapes that are geometrically and anatomically desirable to conform to adjacent vertebral bodies, including but not limited to round, oval, elliptical, annular, D-shaped, C-shaped, and the like.

As shown, the intervertebral disc 10 includes an upper end plate 20, a lower end plate 22, and an intermediate elastic membrane 24, wherein the elastic membrane 24 generally has a lower end plate from the upper end plate 20 ( 22, and is preferably located adjacent to the outer periphery of the disc 10. Alternatively, elastic membrane 24 may enclose and / or enclose upper and lower end plates 12, 14. The elastic membrane 24 may define an internal volume in combination with the upper and lower end plates 20, 22.

The elastic membrane 24 is formed of an elastomer such as polyurethane, silicone, braided polymer, or any other suitable elastic material known in the art. The elastic membrane 24 may be permeable or semipermeable to allow fluid to flow into and out of the disc (described in more detail below). Alternatively, the membrane is impermeable. Preferably, the elastic membrane 24 may inhibit translational motion between the upper and lower end plates 12, 14 and also prevent soft tissue internal growth between the end plates 12, 14 as well as occur within the interior volume. May comprise any wear particles present. The elastic membrane 24 may be attached to the upper and lower end plates 22 by any fixing method known in the art including, but not limited to, binders, ultrasonic welding, screws, nails, mechanical wedging and pins. have.

Alternatively, the elastic membrane 24 may be in the form of bellows that take an “accordion” shape, allowing for expansion and contraction under various loading conditions. The bellows is not limited to the circular grooves formed in each end plate 12, 14, but the top and by any method known in the art, including binders, ultrasonic welding, screws, nails, mechanical wedging and pins. It may be firmly attached to the lower end plates 12, 14. Preferably, the bellows is made of metal, but other materials such as elastomers or polymers may be used. In other embodiments, the membrane 16 may be made of any suitable inelastic material, as would be known by known techniques.

2, the interior 26 of the disk 10 is shown. Preferably, the interior 20 of the disk 10 includes at least one spring element 30, which spring element 30 may have a longitudinal axis. The spring may be oriented such that its longitudinal axis is oriented approximately perpendicular to the plane formed by the upper and lower end plates 20, 22. Alternatively, the spring may be oriented such that its axis forms an acute angle with at least one of the upper and lower end plates. The spring element may have a first end in contact with the lower end plate 22 in a groove or pocket formed in the inner surface 40 of the lower end plate 22. Such pockets or grooves can prevent the spring from displacing laterally with respect to the end plate. The upper end of the spring element 30 may engage an articulation member 34 having a spring engagement surface 33 and an opposing approximately spherical surface 35. The spring element 30 may be a pocket 32 and / or articulation member 34 using suitable fastening methods known in the art, including but not limited to adhesives, ultrasonic welding, screws, nails, press fits and pins, and the like. Can be fixed). Alternatively, the spring element 30 and the articulating member 34 may be integrally formed.

The spherical surface 35 of the articulation member 34 may be configured to be articulated within a socket 36 having a corresponding shape formed on the inner surface 38 of the upper end plate 20. The boundary between the articulation member 34 and the socket 36 is close to a ball and socket shaped connection, and the spherical articulation member 34 may be articulated within the socket 36. The shape and amount of desired joint connection follows the curvature and arc of the spherical surface 35 provided on the joint member 34 and the socket 36. For example, if the spherical surface 35 has the same radius as the socket 36, the disk 10 provides greater support but is more limited in motion. Alternatively, if the socket 36 has a larger radius than the spherical surface 35, the disk 10 may provide for increased articulation and / or translational motion.

In another embodiment, the socket 36 incorporates a smoothing portion that allows the articulation member 34 to translate within the socket so that the upper end plate 20 can translate relative to the lower end plate 22. By providing this translational movement, the disk 10 can cause the axis of rotation to move immediately. Since the joint member 34 and the socket 36 have an external shape other than a sphere, a predetermined joint motion can be obtained. Such other contours may include ovals or ovals, and multiple spheres that may include spherical segments in which the articulation member and the socket are at least two separate or jointly joined together. In addition, although the joint member 34 and the socket 36 are generally shown to have a contour that can mate with their respective surfaces, the corresponding surfaces have a predetermined joint connection between the upper and lower end plates 20, 22. It may take any suitable shape to obtain the mobility of.

Although the disk 10 is shown having a socket 36 associated with the upper end plate 20 and an articulating member 34 associated with the lower end plate 22, the elements may instead have a socket 36 and an articulation element 35. It may be reversed to relate to the lower and upper end plates, respectively. In addition, the socket member may be provided integrally with each end plate, such as to provide a single end plate with a hollow spherical inner surface. In addition, the socket member and the joint member may include any suitable material known in the prior art such as polymer such as ultra high molecular weight polyethylene, titanium, stainless steel and the like. In addition, the articulation surface may include surface abrasion or similar abrasion relief finishes such as diamond finishes, TiNi finishes, etc. to minimize wear, reduce particle production and extend the life of the disc.

The spring element 30 may comprise any suitable elastic member known in the art, including but not limited to helical springs, coil springs, leaf springs or leaf springs, and the like. In addition, the spring element 30 may comprise a metal or polymer, a composite such as chromium alloy, titanium alloy, stainless steel, shape memory alloy, and amorphous alloy. Likewise, spring element 30 may comprise two or more separate spring elements provided in series, in parallel, or a combination of in series and in parallel.

However, the choice of a particular spring element depends on the needs of a particular patient, and the selected spring must be appropriate as it is required for a particular procedure or to mimic the characteristics of a patient's normal intervertebral discs. Therefore, a spring with stiffness suitable for axial compression and lateral bending is selected to provide the following range. Shrinkage / extension: about 0 Nm / deg to about 8 Nm / deg, lateral bending: about −Nm / deg to about 5 Nm / deg, compression about 100 to 500 N / mm. In addition, the outer diameter of the selected spring is about 5 mm to 30 mm, and the height of the spring is about 7.5 mm to 12 mm. It is to be understood that the foregoing is representative dimensions and that the springs used may have any size, shape, strength and flexibility appropriate for the particular patient.

The use of a spring element in combination with the articulation surface provides a combination of articulation, translational motion and compression / buffering between the upper and lower end plates 20, 22 to allow the axis of rotation to move immediately. Articulation may be provided by the interaction of articulation member 35 and socket 36 and / or by bending at least one spring element 30. Compression and cushioning may be provided by the spring element 30, wherein the translational motion is achieved through the selection of a socket having a smooth portion or by bending the spring element such that the articulation member 34 translates within the socket 36. Can be provided.

In figure 2a a disk 10 comprising a plurality of internal spring elements 30 is shown, each spring element 30 having a longitudinal axis of the spring element in a plane formed by each end plate 20, 22. It extends from the upper end plate 20 to the lower end plate 22 so as to be oriented at approximately a right angle. Alternatively, one or more springs 30 may be oriented such that their longitudinal axis forms an acute angle with respect to the plane of the one or more end plates.

The plurality of spring members 30 may be arranged in a suitable configuration to provide uniform cushioning, load support, tension / compression resistance, or the spring elements 30 may be arranged on one side (eg, front) of the disk as compared to the other. Can be strategically arranged to exhibit greater resistance to impact and / or compression on the back side. However, preferably the disk 10 comprises at least one central spring element 30 and at least one peripheral spring element 30 spaced from the central spring 30. In the embodiment shown, a single central spring element is surrounded by a plurality of peripheral spring elements. The central and peripheral spring elements 30 may have approximately the same stiffness or their stiffness may be different. Preferably, the central spring element 30 can have a greater rigidity than that of the peripheral spring element 30. This arrangement results in the disk having a central spring providing primary cushioning and resistance during axial compression and a peripheral spring element 30 providing secondary cushioning and resistance during subsequent steps of axial compression. This provides the desired nonlinear response in response to a compressive load that can closely mimic the response of the patient's original disc.

In FIG. 2A each element 30 is shown having first and second ends associated with the upper and lower end plates 20, 22. The first and second ends of each spring may have associated spherical articulating members 34 that are structured to mate with corresponding spherical sockets 36 formed on the inner surfaces of the upper and lower end plates 20, 22 as described above. have. The combination of the spring and the joint member allows the upper and lower end plates 20, 22 to move relative to each other. For example, the articulating member 34 may be articulated with the upper and lower end plates 20, 22 relative to each other without the occurrence of a resistive twist in the spring element 30 that is present if the ends of the spring are rigidly connected to the end plate. So that it can be articulated within the associated socket 36. Alternatively, each spring element 30 may be attached only to the articulation member 34 at one end, and the other end is attached to the upper or lower end plates 20, 22 as described above.

 Referring to FIG. 2B, the disc 10 includes a spherical articulating element 34 only at one end of the first spring element 30, the other end of the first spring element 30 and both ends of the second spring element 30. The silver may comprise a plurality of spring elements 30 installed in corresponding pockets or grooves in the upper and lower end plates 20, 22 (arrangement and connection of these grooves, and associated spring elements for the embodiment of FIG. 2). As described above). As shown in FIG. 2B, the first spring element 30 is preferably attached to a hemispherical element 34 that matches the corresponding socket 36 located on the upper end plate or the lower end plate 20, 22. The plurality of second spring elements 30 surrounding the first spring element 30 are directly attached to the upper and lower end plates 20, 22 as described above. In one embodiment, the first spring may be attached to one hemispherical element 34 and the plurality of second spring elements 30 may be attached to two hemispherical elements 34. As with the embodiments described above, the number and stiffness and arrangement of the springs as well as the selection and placement of the articulating elements and sockets 36 can be made in any suitable combination so that they are appropriately provided to mimic as close as possible to the characteristics of the standard intervertebral disc, It can be made in any combination that provides the appropriate properties.

Referring to FIG. 2C, the disk 10 may include an elastomeric strut 54 positioned around the central spring element 30. The strut 54 has a longitudinal axis and a first end and a second end, each end of which may be integrated with the upper end plate or the lower end plate 20, 22. Elastomeric struts 54 may be located in grooves 32 formed in the combined inner surfaces 38, 40 of the upper and lower end plates 20, 22 to resist displacement. Elastomeric strut 54 may provide essentially the same function as the peripheral spring element 30 described above, for example, to provide a disk 10 having compressive force resistance and shock absorption and to resist movement. Elastomeric struts 54 may be formed of any suitable material known in the art but not limited to polyurethane or silicone. Many individual struts 54 can be provided, and individual struts can take a variety of shapes to provide adequate rigidity or resistance support for the end plates. Thus, the struts 54 may be cylindrical, square, rectangular, or the like, and may have appropriate cross sections, such as circular, triangular, elliptical, and the like. The struts can also be provided with continuous or discontinuous cross sections and can be made of several layers of materials, such as having alternative elastomers and metal or polymer layers. Strut 54 may also be hollow and may be ring shaped. The ring shaped strut 54 can be formed to enclose at least a portion of the first spring element 30. As in the previous embodiment, the ends of the struts 54 may be connected to the end plate using any suitable method in the art, including press fits, adhesives, and the like. One or more struts may also be provided to be moved within the associated groove or grooves. The arrangement, number, and shape of the struts 54 are not critical, but may instead be any combination to provide a disk 10 that mimics the characteristics of a standard intervertebral disc of a patient or provides characteristics suitable for a particular procedure.

The inner surfaces 38, 40 of the end plates 20, 22 may be porous such that the elastomeric struts 50 are incorporated into the corresponding surfaces of the upper and lower end plates 20, 22 during manufacture, such as by molding elastomers on the end plates. . Membranes and / or barriers are also included in the end plates 20, 22 to limit the depth of impregnation and bony ingrowth of each of the bones.

The disk 10 of the present invention may also include a membrane 24 and a valve (not shown), the valve providing access to the interior of the disk 10 so that liquid may form inside the disk 10 ( 26 or is removed from the disk 10. The valve is preferably a one-way valve as is known to those skilled in the art, and therefore can not escape from the interior 26 of the disk 10 when the fluid is injected. Preferably, the valve is disposed through the elastic membrane 24, but the valve may be disposed through the upper end plate and / or the lower end plate 20, 22. If the valve is disposed on the upper end plate and / or the lower end plate 20, 22, the passage preferably comprises an interconnect 26 to the valve and the interior 26 of the disc 10.

The fluid may be a gas, liquid, gel or other combination that provides sufficient shock absorption during axial compression of the disk 10, while restricting the movement of the joint or upper end plate 20 and the lower end plate relative to each other. can do. Preferably the fluid is incompressible, such as saline or carbonated water. Usually, fluid may be injected into the interior 26 of the disk 10 before inserting the disk 10 between adjacent vertebrae. In addition, fluid may be dispensed in place to facilitate insertion and subsequent distraction of the disk 10 between adjacent vertebrae. The rigidity and dissipation capacity of the disk 10 may be a function of the amount of fluid injected into the interior 26 of the disk 10. In general, as more fluid is provided into the interior 26 of the disk 10, the disk 10 is more rigid and the dispersing capacity is greater. In addition, flexibility and increased joints may be realized by filling only a portion of the interior 26 of the disc 10. As a result, the variable filling of the interior 26 of the disk 10 with fluid can vary as the overall height H of the disk 10 is required by the needs of the individual patient.

Depending on the location of the spine where the disk 10 is implanted, the disk 10 is preferably restored to a height in the range between about 4 mm and about 26 mm. In addition, the disk 10 is preferably restored to lordosis in the range of about 0 ° to 20 °. The disk 10 also recovers axial stiffness from about 1 Nm / deg to about 11 Nm / deg, flexion / extension from about 0 Nm / deg to about 7 Nm / deg and longitudinal bending of about 0 Nm / deg to about 5 Nm / deg. do. In addition, the disk 10 preferably provides compressive stiffness of about 100 N / mm to about 5000 N / mm, and tensile stiffness of about 50 N / mm to about 1000 N / mm. In addition, depending on the location of the spine where the disk 10 is mounted, the intervertebral disc 10 may have a flexion / extension of about 5 ° to about 45 °, a longitudinal bend of about 3 ° to about 33 ° and about 1 ° to about 60 °. It is desirable to allow a range of motion of axial rotation of the. The additional plate 10 also preferably allows for axial compression in the range of about 0.2 mm to about 2 mm.

Preferably, the upper and lower end plates 20, 22 are made of metals such as titanium, stainless steel, titanium alloys, cobalt-chromium alloys, shape memory alloys or amorphous alloys. In addition, the upper and lower end plates 20, 22 are rigid polymer, peak (PEEK) or ultra high molecular weight polyethylene (UHMWPE), ceramics, composites, cortical, cancellous, taga grafted. (allograft), autograft, xenograft, bone, including demineralized or partially demineralized bone, or other suitable material provided as load support. The material selected for the endplates is more preferably chosen to minimize wear.

In addition, the articular surface in the intervertebral disc of the present invention includes a surface polishing or similar wear reduction treatment such as diamond treatment, TiNi treatment or the like, which minimizes wear, reduces particle formation, and increases disk life.

The outer surfaces of the upper and lower end plates 20, 22 may be approximately flat wedge shapes or the like. The outer surfaces of the upper and lower end plates 20, 22 also have a dome shape that has a radius formed in the sagittal and coronal surfaces to approximately fit the end vertebrae of the adjacent vertebrae so that they are better coupled to the jersey. Can be.

In addition, as shown in FIG. 1, the disk 10 includes migration resistant features, such as structures such as spikes 18, on the outer surfaces of the upper and lower end plates 20, 22. FIG. can do. The anti-movement shape may facilitate the engagement of the disk 10 with the end of the adjacent spine by providing a mechanical interlock as a result of penetration and / or deformation of the end of the adjacent spine. The initial mechanical stability imposed by the spikes 18 minimizes the risk of, for example, post-stable instability, movement, dislodging, or expulsion of the disk 10. Other anti-moving features include, without limitation, flaps, teeth, deployable teeth, deployable spikes, plastic spikes, plastic teeth, fins on the upper and lower end plates 20, 22. , Insertable or deployable pins, anchors, screws, ridges, serrations, or other similar structures. As shown in FIG. 3A, deployable spikes 41 may be provided, and cam mechanism 43 may be used to deploy the spikes. In addition, as shown in FIG. 3B, the deployable spike may be shaped to be deployed by a mechanism (not shown). As shown in Figs. 3C-3E, examples of the plastic spike 44, the one-shaped teeth 45 and the anchor 46 are shown. Alternatively and additionally, adhesive may also be used to secure the disk 10 to the adjacent vertebrae.

In addition, the upper and lower end plates 20 and 22 are also coated with a bone growth inducing substance such as hydroxyapatite to promote bone internal growth to permanently fix the disk 10 to the adjacent vertebrae. can do. In addition, the upper and lower end plates 20, 22 may have a rough, porous surface to promote internal growth of the bone. In addition, the upper endplate or lower endplates 20, 22 may have a laser treated endplate layer to create a porous structure, or may incorporate an osteoconductive / osteoinductive scaffold. The end plates 20, 22 may also be made of a bone conductive and / or bone inducible material that promotes internal growth of the bone. The end plates 20, 22 further comprise a membrane and / or a barrier to limit the depth of internal growth of the bone allowed.

The upper and lower end plates 20, 22 may also have an implant instrument attachment structure, an implant instrument guide structure, and an implant instrumentation attachment, guiding, and retaining structure. For example, the end plates 20, 22 may have a dovetail to receive a mechanism used for implantation and / or dispensing of a hole, slot, screw or spine. For example, the disk may include a slot formed in the upper end plate and / or the lower end plate 20, 22, the slot being shaped to receive an implant insertion device, a dispenser, or both.

As a result of the materials and structural components used, the disk 10 may allow flexion / extension, longitudinal bending, axial rotation and translational motion depending on the load imposed on the intervertebral disc. In addition, under various vertebral loading conditions resulting from spinal movement, the spring element 30 is compressed, inclined, articulated, and / or curved in varying amounts.

4 and 4A, a second embodiment of the intervertebral disc 100 is shown. Similar to the embodiment described above, the outer shape of the disk 100 is structurally anatomically roughly coincident with the adjacent vertebral body, including, but not limited to, circular, egg-shaped, elliptical, annular, gangnam-shaped, D-shaped, C-shaped, and the like. It may take a predetermined shape. As shown, the disc 100 includes an upper end plate 102, a lower end plate 104, and an elastic membrane 106, and the elastic membrane 106 includes upper and lower end plates that form an inner space 108. 102, 104). The end plates 102 and 104 and the elastic membrane 106 are similar to the end plates and the elastic membrane described above in other embodiments. The disk 100 also includes a valve (not shown), which allows the valve to be accessible to the interior 108 of the disk 100 to allow insertion or removal of fluid as described above in other embodiments. do. The disk 100 may also have a non-moving shape, permanent flexion means and / or implant mechanism attachment structure, implant instrument guide structure, and implant implant retention, as described above in FIGS. 3A-3E and other embodiments. Include a structure.

The disk 100 may further include a leaf spring 110 having a first end 112 and a second end 114. The first end 112 can be attached to the upper end plate 102, while the second end 114 of the leaf spring 110 has a roller 130 that can roll on the inner surface of the upper end plate 102. It may include. The leaf spring may have a central portion 116 disposed between the first end 112 and the second end 114, which central portion 116 may have a concave-convex shape. The convex surface may generally face the lower end plate 104, and the concave surface may generally face the upper end plate 102. Lower end plate 104 may include a surface configured to receive an intermediate section 116 that is configured to mate, articulate, slide, and pivot with the ball-shaped inner surface in the socket. Although leaf spring 110 is described herein as attached to the upper end plate, alternatively the uneven middle section 116 may be attached to the lower end plate 104 to interact with the inner surface of the upper end plate 102. Although the articulation surface of the leaf spring 110 is shown as disposed near the center of the leaf spring, the articulation surface may be positioned at any point along the length and / or width of the leaf spring as appropriate to provide the desired articulation. Can be located.

The non-attached second end 114 of the leaf spring 110 may be provided with a roller 130 on the axle 132, the roller 130 is freely rotatable about the axle (132). The second end 114 of the leaf spring 110 may slide or roll along the inner surface of the upper end plate 102 during axial loading or compression and during axial unloading or tensioning. Accordingly, the leaf springs of this embodiment are allowed to translate when bent, providing a greater range of flexibility when compared to leaf springs constrained at both ends. In another embodiment, leaf spring 110 may have a rounded end instead of roller 130 to slide directly along the inner surface of upper end plate 102.

Lower end plate 104 may include a pocket 106 for receiving pad 120. The pad 120 includes a lower surface for engaging the lower end plate 104 and an upper surface including a concave section 122 constructed and dimensioned to mate with the enlarged intermediate convex section 116 of the leaf spring 110. Can have The type and amount of joints provided by the springs and pads can be adjusted by controlling the curvature provided on the concave section 122 and the intermediate section 116. If the intermediate section 116 has the same diameter as the concave section 122, the disk 100 may provide greater support but more constrained movement. In addition, when the concave section 122 has a larger radius of curvature than the intermediate section 116, the disk can provide increased joints.

In addition, the intermediate section 116 and the concave section 122 can take on different contours to achieve the desired joint. Concave section 122 of pad 120 may be convex to mate with concave middle section 116. Further, although the concave sections 122 and the intermediate member 116 are shown to have an outline that generally allows mating of their surfaces, an unmatched geometry can be provided to achieve the desired joint.

In addition, the compression and sliding of the leaf spring 110 may vary depending on the area or regions of loading. For example, loading one end of the disk 100 may result in greater compression of the disk 100 as compared to the opposite end of the disk 100. In addition, the pad 120 and the pocket 106 can be configured to cause the pad to translate within the pocket 106. The translational movement of the leaf spring 110 relative to the pocket 106 and the variable movement, ie compression, of the leaf spring 110 may allow for a momentary axis of rotation to move.

Leaf spring 110 is any suitable known in the art including metals such as, for example, polymers, ceramics, composites, cobalt chromium alloys, titanium alloys, stainless steels, shape memory alloys, and amorphous alloys. It may be formed from a material. Pad 120 may likewise be formed of similar material.

Depending on the location of the vertebrae where the disc 100 is inserted, the disc 100 preferably recovers height, natural spine curve (or sagittal balance), stiffness, provides compressive stiffness, and is described in connection with the above embodiments. Allows a range of motion similar to that.

5, a third exemplary embodiment of intervertebral disc 150 is shown. Similar to the embodiment shown, the disc 150 is geometrically and adjacent to the vertebral body, including but not limited to round, oblong, oval, annular, kidney beans, D-shaped, C-shaped, and the like. It may take any shape that is anatomically broadly consistent. As shown, the disc 150 includes an upper end plate 152, a lower end plate 154, and an intermediate elastic membrane 156, and an elastic membrane 156 in combination with the upper end plate 152 and the lower end plate 154. ) Defines the interior volume 158. The end plates 152, 154 and the elastic membrane 156 are similar to those described above in connection with other embodiments. In addition, the disk 150 may include a valve (not shown), the valve 158 of the disk 150 to allow insertion or removal of the fluid as described above in connection with other embodiments. Provide access to The disc 150 may also include migration resistant properties, permanent fixation means and / or implantation device attachment, guide and retention structures as described above with respect to FIGS. 3A-3E and the above embodiments. .

The disc 150 may include a central articulation member 160 attached to either the upper end plate 152 or the lower end plate 154, preferably to the lower end plate 154. The articulation member 160 may have a convex lower surface 162 configured and dimensioned to articulate with respect to the concave surface 164 formed on one inner surface of the lower end plate 154. The curvature of the corresponding articulation surfaces 162, 164 may be manipulated as needed to provide the desired amount of joint and translational motion between the end plates 152, 154 as already described above in connection with other embodiments. Can be.

The articulation member 162 may also include a concave bottom surface configured and dimensioned to mate and articulate with respect to the convex surface formed on the inner surfaces of the opposing end plates 152, 154. In addition, the concave surface 164 may be integrally formed on the inner surface of one of the end plates 152, 154 or may be separately formed and mounted thereon. Mounting the concave surface 164 on the inner surface of one of the end plates 152, 154 allows the concave surface 164 to be made of a different material than the material of the associated end plate, for example polyethylene or other polymer, or Or the shock absorbing material may be provided as will be described in more detail below.

The articulation member 160 may be attached to one of the end plates 152, 154 by any fastening method known in the art, including but not limited to adhesives, ultrasonic welding, screws, nails, mechanical wedges and pins. Can be. However, preferably, the articulation member 160 may be attached to one of the end plates 152, 154 via the intermediate shock absorbing layer 170. The shock absorbing layer 170 may be an elastomer, molded or bonded polymer fibers, polyurethane, silicone or any other suitable elastic material having suitable shock absorbing properties. Articulation member 160 may be made from metal, polymer, composite, ceramic, or any combination thereof.

In addition, the disk 150 may be provided with an additional elastic membrane configured to restrict and / or secure the articulation member 160 to one of the end plates 152, 154, and / or to enclose the shock absorbing layer 170. 172). The additional elastic membrane can be a bellow that can provide shock absorption, compressive resistance, and added stability to the articulation member 160 upon shearing.

Depending on the location of the vertebrae where the disk 150 is inserted, the disk 150 preferably recovers height, natural spine curve (or sagittal balance), stiffness, provides compressive stiffness, and has been described in connection with the above embodiments. Allows a range of motion similar to that.

As a result of the materials, geometries and elements used, the disk 150 may allow flexion / tensiles, lateral bending, axial rotation and translational motion, depending on the loading state applied to the intervertebral disc. In addition, under various spinal loading conditions, the shock absorbing layer disposed between the articulation member 160 and one of the end plates 152, 154 may depend upon the location of the compressed and / or bent region relative to the region or regions of loading. Can compress and / or bend variable amounts. The disc 150 also allows different regions of the disc 150 to compress variable amounts.

Referring to FIG. 6, a fourth exemplary embodiment of the intervertebral disc 200 is shown. The disk 200 has a generally circular shape with an upper end plate 202, a lower end plate 204 and a slotted core 206 having an upper curved surface and a lower flat surface. The disk 200 may take any other shape that geometrically and anatomically appropriately matches an adjacent vertebral body, including but not limited to kidney, bean, oval, annular, elliptical, C-shaped, D-shaped, and the like. . Other features described above for other embodiments, such as movement resistance structures, permanent fixation features, and / or implantation instrument attachment, guide and retention structures, may be included in the end plates 202, 204. In addition, the outer surfaces of the upper and lower end plates 202, 204 may be substantially flat, wedge shaped, or the like. In addition, the outer surfaces of the upper and lower end plates 202, 204 may be domes formed with their diameters defined within the sagittal and coronal planes to generally match the shape of the ends of the adjacent vertebrae, thereby in situ. Provide a better fit. Preferably, the upper and lower end plates 202, 204 can be made of metal. Alternatively, however, the upper and lower end plates 202, 204 may be made of any of the end plate materials described above in connection with the previous embodiment.

As shown, the lower end plate 204 preferably includes a pocket 208 located on its inner surface, which pocket 208 is designed to receive the lower flat surface of the slotted core 206. Alternatively, the slotted core 206 and the lower end plate 204 can be formed as one piece. When the core is formed as a separate piece, it may comprise a different material than the end plate 204, such that the metal end plate may be provided to have, for example, a polymer mating characteristic core 206.

When the core 206 and the end plate 204 are formed separately, the disc 200 also holds a c-ring (not shown) or pocket 208 to hold the core 206 in the end plate pocket 208. And similar structures such as rings or ribs located within or adjacent the pocket 208. Such a ring may be configured to prevent the core from translating relative to the end plate 204, or may permit translation of the core in one or more directions. Alternatively, the core 206 may be retained in the pocket 208 by welding, pressing, staking, or bonding the cap to the lower end plate 204, such that the cap is the core 206. Cover part of it.

While pocket 208 is shown as having a circular shape, the pocket may have any other suitable shape including, but not limited to, oval, oval, kidney bean, rectangular, and the like. If the core and end plate are formed in separate portions, the pocket 208 is wider or longer in length than the slotted core 206, so that the core 206 translates in the pocket 208 during operation. Let's do it. Alternatively, the pocket 208 may have a structure of various dimensions needed to allow translational movement of the core 206 within the pocket only in specific directions. Thus, the pocket may be provided with the same general width as the core in all but one direction, and the pocket is wider than the core in the one direction (eg, forward and backward direction). Thus, pockets wider than the core along the fore and aft axis cause the core to translate in a forward and backward direction during use. Corresponding modifications to the pocket geometry can be made to allow translational motion in other directions, such as intermediate lateral translational motion.

The inner surface of the upper end plate 202 may have a concave bonding feature 210 configured to receive the upper curved surface 212 of the slotted core 206. Preferably, the joining features 210 allow the upper end plate 202 to be articulated relative to the slotted core 206. This joining feature 210 may be integral to the upper end plate 202 or may be formed by being fitted to the end plate as a separate part. If the joining features are formed in separate portions, they may include a material different from the endplate 202. Thus, a metal end plate may be provided, for example, with polymer bonding features 210.

As previously described with respect to other embodiments, the articulation surface may be reversed, ie, the joining feature 210 may be provided in a convex shape, and the slotted core may be provided with a concave surface. . In addition, the type and amount of articulation and / or translational motion provided by the disk of this embodiment may likewise be adjusted by adjusting the curvature of the convex and concave surfaces as previously described in connection with other embodiments. By allowing articulation and translational movement between the end plates, a mobile instantaneous rotational axis that approximates the movement of the natural intervertebral disc is allowed.

Slotted core 206 may be elastic and allow compression under axial load conditions to provide shock absorption. Thus, core 206 may have at least one slot 216 cut into its periphery. Slot 216 may be straight or curved and may extend horizontally, vertically, or obliquely. Slots 216 may also vary in length and width and may be provided at various depths through the core. Slot 216 may increase the compressibility of slotted core 206, providing additional shock absorbing capability to disk 200. The arrangement and structure of the slots provided in the core 206 may be any combination suitable to provide the desired degree of compressibility.

While shown as having a circular foot, the slotted core 206 can be any other shape, including egg-shaped, rectangular, elliptical, and kidney beans. Preferably, the shape of the slotted core 206 matches the shape of the pocket 208 formed on the inner surface of the lower end plate 204. Slotted core 206 may be formed from a material that includes, for example, a ceramic, composite, polymer, or metal such as a cobalt-chromium alloy, stainless steel, and a titanium alloy. Alternatively, the slotted core 206 may consist of two elements (not shown) of different materials. In addition, as described above, the slotted core 206 may be fabricated integrally with the lower end plate 204.

Disk 200 may also include rigid restoration features such as elastic membranes, elastomer rings, bellows, springs or fluids as previously discussed in connection with other embodiments. Disk 200 may also include additional shock absorbing features as previously discussed in connection with other embodiments.

The disk 200 end plate may have a movement preventing structure provided on at least one or both outer surfaces of the end plate to prevent movement, removal or release of the end plate within and from the end of the adjacent vertebrae. The anti-movement structure includes flaps, spikes, teeth, fins, deployable spikes, deployable teeth, flexible spikes, flexible teeth, differently shaped teeth, insertable or inflatable pins, screws, hooks, teeth , Ribs and organized surfaces.

In addition, the upper and lower end plates of disk 200 may also be coated with a bone growth inducing or performing material to promote bone growth to permanently secure the disk to adjacent vertebrae. Alternatively, the upper and lower end plates may have a rough surface, a porous surface, a laser treated end plate layer, and may include bone conduction / oskeletal scaffolds or integral bone conduction and / or to promote bone growth. Osteoinducing materials may be provided or fabricated from them.

Depending on the location of the vertebrae where the disc 200 is implanted, the disc 200 restores height, lordosis, stiffness, provides compressive stiffness, and provides a range of movements intended to mimic natural intervertebral disc movement. You can either allow or allow as required for a particular condition.

Also preferably, as discussed by the previous embodiment, the articulation surface of the disk 200 is a surface polished or diamond finish, TiNi, to minimize wear, reduce particle production and increase disk life. Similar wear reduction finishing processes such as finishing.

As a result of the materials, geometries and components used, the disk 200 may allow flexion / extension, lateral curvature, axial rotation and translational motion, depending on the load conditions imposed on the intervertebral discs. In addition, under various vertebral loading conditions, the slotted core 206 may be variably compressed and may be compressed in different amounts for different regions of the slotted core 206, depending on the location and type of spinal load. The different regions of the end plates 202, 204 may be compressed in different amounts. By varying compression of the slotted core 206 in this manner also a movable instantaneous axis of rotation is permitted.

With reference to FIG. 7, a fifth exemplary embodiment of intervertebral disc 250 is shown. Disk 250 has a generally circular shape with an upper end plate 252, a lower end plate 254, a cap 256, and a ring spring 258. However, the disc 250 may have other shapes that are preferably geometrically and anatomically consistent with adjacent vertebral bodies, including but not limited to kidney beans, eggs, rings, ovals, ellipses, C-shapes, D-shapes, and the like. have.

As shown, preferably, the lower end plate 254 includes a pocket 260 located on its inner surface, which pocket 260 has a ring spring 258 having a tapered outer surface and a cylindrical inner surface. It is designed to accommodate. Preferably, pocket 260 has a tapered inner surface that joins the tapered outer surface of ring spring 258. While pocket 260 is shown as being circular or conical, pocket 260 may have any other shape including, but not limited to, oval, elliptical, kidney bean, or rectangular.

The pocket 260 may be larger than the ring spring 258 in dimension to allow the ring spring 258 to translate within the pocket 260. As in the pocket of the previous embodiment, the pocket 260 can be specifically dimensioned to allow the ring spring 258 to translate in a limited direction. By allowing a translational movement, a moving instantaneous axis of rotation is created. This movable instantaneous axis of rotation mimics the movement of the natural intervertebral disc more naturally.

The disk 250 also has a similar type of structure, such as a lip or ring, located in or adjacent to the c-ring (not shown) or the pocket 260 to hold the ring spring 258 in the pocket 260. It may include. Alternatively, ring spring 258 may be retained in pocket 260 by any means known in the art, including but not limited to welding, press fit, staking, or joining. have. As described above, the ring spring 258 is held in the pocket 260 in a manner that allows the ring spring 258 to translate within the pocket 260. In one embodiment, the ring spring and cap may be retained in the pocket 260 by a lid that couples the lower end plate 254 and covers at least a portion of the ring spring 258 and / or the cap 256. .

Preferably, the ring spring 258 is a spring-like element that is compressed under axial load to provide shock absorption, flexure and compression resistance. Although shown as having a common C-shaped with circular foot, the ring spring 258 can be any other shape, including ovoid, rectangular, oval, and kidney beans. Preferably, the shape of the ring spring 258 matches the shape of the pocket 260 formed on the inner surface of the lower end plate 254. Ring spring 258 may be formed of any suitable material known in the art, including, for example, ceramics, composites, polymers or metals such as cobalt-chromium alloys, stainless steels, and titanium alloys.

As shown, the ring spring 258 has a top surface 264, bottom surface 266, outer surface defining a central bore 272 that coincides with a shank 276 formed on the cap 256. Has a surface 268 and an inner surface 270. Preferably, the outer surface 268 of the ring spring 258 is tapered to coincide with and engage with the inner surface of the pocket 260. The ring spring 258 may also include at least one slot 262 formed into and / or cut into the perimeter. Slot 262 may be straight or curved and may extend horizontally, vertically, or obliquely. Slot 262 may also vary in length and width. Preferably, as shown, the ring spring 258 extends from the top surface 264 of the ring spring 258 to the bottom surface 266 and from the outer surface 268 of the ring spring 258 to the inner surface. One vertical slot 262 extending to 270. By including this slot 262, the compressibility of the ring spring 258 is increased to provide additional shock absorbing capability to the disk 250.

In alternative embodiments, the ring spring 258 travels in a partial path from the top and / or bottom surfaces 264 and 266 through the thickness of the ring spring 258 to provide the desired compressive properties of the disk (not shown). ) May include a plurality of slots 262.

The disk 250 may also include a cap 256 having an extended body section 274 and a handle 276. The junction between the extension body section 274 and the handle 276 may form a shoulder 278, the handle 276 being configured and dimensioned to be received within the central bore 272 of the ring spring 258. Once defined, the shoulder is configured to engage the top surface 264 of the ring spring so that the cap 256 can be seated on top of the ring spring 258 when the two parts are assembled. In one embodiment, the central bore 272 is larger than the handle portion 276, so that the ring spring (through the closure of the gap formed by the at least one slot 262 when compressive force is applied on the disk 250). 258). Additionally, by providing a central bore 272 that is larger than the handle 276, the cap 256 can translate relative to the ring spring 258.

As described above, the shoulder 278 of the cap 256 is in contact with the top surface 264 of the ring spring 258. Thus, the axial load applied to the cap 256 can be transmitted directly to the ring spring 258 to push the ring spring downward into the pocket 260. When ring spring 258 is pressed into pocket 260, the inclined outer surface 268 of ring spring 710 is inclined surface of pocket 260 in the process of compressing at least one slot 262. Combine with This elastic compression of ring spring 258 under load provides the desired shock absorption and compression resistance. The size and number of slots provided in the ring spring can be chosen to be suitable to provide the desired compression characteristics of the disk.

The axial displacement of the ring spring 258 may be a decrease in the depth of the pocket 260, a decrease in the width of the slot 262, an increase in the thickness and / or length of the handle 276, or any or all of these options. May be limited by a combination of these. Alternatively, a coil spring or elastic layer (both not shown) may be provided in the pocket 260 to provide an upward bias against the ring spring 258.

As described above, the disc 250 also includes an upper end plate 252. Preferably, the inner surface of the upper end plate 252 includes a mating surface 280 that is dimensioned and configured to join the upper surface of the expanding body section 274 of the cap 256. Preferably, mating surface 280 on top end plate 252 has a concave surface configured to articulate with a convex surface formed on the top surface of cap 256. Alternatively, mating surface 280 may comprise a convex surface and the top surface of cap 256 may be concave. As discussed above in connection with another embodiment, the curvature may be adjusted for one or both surfaces to provide the desired joint connection and translational movement between the upper end plate and the cap 256.

In other embodiments, mating surface 280 may be provided separately from upper end plate 252. In this case, mating surface 280 includes a material different from that of endplate 252 (eg, the endplate may be titanium, while mating surface may be UHMWPE). In addition, articulation of disk 250 The cotton may include a surface polishing or similar wear reduction finish, such as diamond finish, TiNi finish, or the like, to minimize wear, reduce particulate generation, and enhance disk life.

In other embodiments, individual caps 256 may be removed and ring springs 256 may be incorporated with convex top surfaces configured to articulate within mating surface 280 of top end plate 252.

The disk 250 of this embodiment may include additional properties described above in connection with other embodiments such as moving resistance structures, permanent fixation properties such as porous surfaces or coated surfaces, and / or insertion instrument attachments, and guides And retaining structures may be included in the end plates 252, 254. In addition, the outer surfaces of the upper and lower end plates 252 and 254 may be generally wedge shaped. In addition, the outer surfaces of the upper and lower end plates 252, 254 may be hemispherical in shape whose radii are formed in the arrow and tubular planes to generally match the shape of the ends of adjacent vertebrae to provide a better fit in place. . The outer surface may further comprise at least one groove, slot or other feature such that the disk can be engaged by the insertion mechanism. Preferably, the upper and lower end plates 252 and 254 may be made of metal. However, the upper and lower end plates 252 and 254 may be made of other materials as described above.

In addition, the disk 250 may include rigid recovery properties such as elastic membranes, rubber rings, bellows, springs or fluids as described above in connection with other embodiments. In addition, the disc 250 may be incorporated with any of the shock absorbing properties described above in connection with other embodiments.

Preferably, depending on the location of the vertebrae where the disk 250 is inserted, the disk 250 restores height, vertebral deterioration and stiffness, provides compressive stiffness, and provides a range of motion similar to that described with respect to the previous embodiment. Make it possible.

As a result of the materials, shapes and components used, the disk 250 enables bending / expansion, lateral bending, axial rotation and translational motion depending on the load conditions. Also, under various spine loading conditions, the ring spring 258 can compress a variable amount. This variable compression of the ring spring 258 allows for a moving instantaneous axis of rotation. In addition, the ring spring 258 allows different portions of the disk 250 to compress a variable amount.

8, a sixth exemplary embodiment of a disk 300 of the present invention is shown. The disc 300 has a generally circular shape with a winged leaf spring having an upper end plate 302, a lower end plate 304, and a side end 310. However, the disk 300 is preferably other geometrically and anatomically matched to adjacent vertebral bodies including, but not limited to, kidney beans, long, round, oval, C-shaped, D-shaped, and the like. It can take shape. Other features described above in connection with other embodiments, such as movement resistance structures, permanently curved characteristics and / or insertion instrument attachment, guide and retention structures, may be included in the outer surfaces of the end plates 302, 304. In addition, the outer surfaces of the end plates 302, 304 may be generally wedge shaped. The outer surfaces of the upper and lower end plates 302, 304 may be hemispherical in shape whose radii are formed in the arrow and tubular planes to generally match the shape of the ends of adjacent vertebrae to provide a better fit in place. Preferably, the upper and lower end plates 302, 304 are made of metal. However, the upper and lower end plates 302 and 304 may be made of other materials, as described above.

As shown, the lower end plate 304 preferably includes a blocking portion 308 configured to be received at least at the center of the winged leaf spring 306, and a blocking portion 308 (ie, pocket) on the inner surface. The lower end plate 304 may support the winged leaf spring 306 along at least a portion of its side end 310, the central portion 314 of the leaf spring 306 seated within the blocking portion 308, There is a gap between the bottom face of the leaf spring 306 and the bottom face of the blocking portion 308. Therefore, when the leaf spring is subjected to the axial compressive load, the side end portion 110 has the central portion 314 of the leaf spring as the blocking portion 308 until the lower surface of the central portion contacts the lower surface of the blocking portion 308. It is curved so that it can be pressed downward. The size of the initial gap between the leaf spring and the blocking portion may be selected according to the stiffness of the side end 310 to achieve the maximum axial compression of the disk 300 and the desired compression stiffness. The side ends may have substantially the same stiffness, or their stiffness may be substantially different. Similarly, the lower portion of the blocking portion 308 may be generally flat or inclined such that the central portion of the leaf spring may be more deflected in the desired direction. The stiffness and gap can be selected to be suitable to mimic the characteristics of the patient's vertical weight sign or to suit a particular procedure.

In addition, the depth of the blocking portion 308 is preferably a depth sufficient to allow the wing-shaped leaf spring 306 to be curved, but may be well designed within the disk 300 to mimic the compressive resistance and shock absorbing properties of the original intervertebral disc. Or because the curvature of the vane leaf spring 306 providing adequate compressive resistance to a particular procedure provides impact modulus and compressive resistance, the depth of the block 308 may be such that the curvature of the vane leaf spring is not destroyed. Has depth.

Although the blocking portion 308 is shown in a rectangle, the blocking portion 308 may take any other shape, including but not limited to round, oblong, oval, kidney beans or rectangular. The blocking portion 308 may have a larger dimension than the central body portion 314 of the winged leaf spring 306 that enables translational movement of the winged leaf spring 306 within the blocking portion. By allowing translational motion, a momentary axis of rotation is created which more naturally simulates the movement of the original intervertebral disc.

The disc 300 has an upper end plate 302 having an inner surface including a mating surface 316 dimensioned and configured to mate with the articulation surface 312 on the central body 314 of the winged leaf spring 306. ) May be included. Preferably, mating surface 316 is concave. Alternatively, however, the mating surface may have a convex profile, the mating surface 316 of the upper end plate 302 may be convex, and the articulation surface 312 of the central body 314 may be concave. As described above in connection with another embodiment, the curvature of the concave / convex surface may be selected to provide a predetermined amount of joints that simulate the characteristics of the vertical weight signage, or may be as required for a particular procedure.

In other embodiments, the side ends 310 of the winged leaf spring 306 may have a constant thickness, length, and width. Alternatively, side end 310 may have a variable thickness, length and / or width. The translational motion from the side end 310 to the central body 314 may be gradual or the translational motion may be abrupt so that the thickness increases gradually from the outer periphery of the side edge 310 toward the articulation surface 312. Can be. In addition, the winged leaf spring 306 may include one or more slots or grooves in one of the side ends (not shown) to further increase the flexibility of the spring.

Although shown as having a rectangle, the winged leaf spring 306 can be any other shape, including oblong, round, oval, kidney beans, and the like. Preferably, the shape of the winged leaf spring 306 matches the shape of the blocking portion 308 formed on the inner surface of the lower end plate 304. The vane leaf spring 306 is preferably made of a ceramic, composite, polymer, or metal such as cobalt chromium alloy, stainless steel, and titanium alloy, for example.

Alternatively, the disk 300 may include a lead or ring member (not shown) and is configured to hold the winged leaf spring 306 in the blocking portion 308 to prevent the spring 306 from being removed. prevent. In this example, the lead or ring member may be attached to the lower end plate 304 after the vane leaf spring 306 is disposed in the blocking portion 308. The lead or ring member may be attached to the lower end plate 304 by any fastening means known in the art, including but not limited to pins, screws, welding, bonding, press fits, and the like.

In addition, the disk 300 may include rigid restoration properties such as elastic membranes, rubber rings, bellows, springs, or fluids described in connection with various other embodiments. The disk 300 may incorporate the additional shock absorbing properties described above in connection with other embodiments such as, for example, the manufacture of a disk of elastic material or the like.

In addition, the articulation surface of the disk 300 may be provided with a similar wear reduction finish, such as surface polishing or diamond finish, TiNi finish, etc., to minimize wear, reduce particulate generation and increase the life of the disk.

Depending on the location of the vertebrae where the disc 300 is inserted, the disc 300 preferably restores height, original spine curve (or sagittal balance), stiffness, provides compressive stiffness, and the previous embodiment. Allow a range of movement similar to that described for.

As a result of the material, shape, and components used, the disk 300 may allow for bending / extension, lateral bending, axial rotation, and translational motion depending on the loading conditions added on the intervertebral disc.

9, a seventh exemplary embodiment of the intervertebral disc 350 is shown. The disc 350 generally has a circular shape with an upper end plate 352, a lower end plate 354, a leaf spring 356, and an articulated cap 358. However, disk 350 may take other shapes that conform geometrically and anatomically adjacent to the vertebral body, including, but not limited to, kidney beans, oblong, annular, oval, C-shaped, D-shaped, and the like. Can be. Other features previously described for other embodiments, such as movement resistance structures, permanent fixation properties, and / or implant device attachment, guiding, and retention structures may be included on the end plates 352, 354. In addition, the outer surfaces of the upper and lower end plates 352 and 354 may be generally flat wedges or the like. In addition, the outer surfaces of the upper and lower end plates 352, 354 are generally domed shaped with radii determined in the sagittal and parietal planes to match the end shape of adjacent vertebrae to provide better fitting in place. Can be. Preferably, the upper and lower end plates 352, 354 are made of metal. However, the upper and lower end plates 352 and 354 may be made of the other materials previously described.

As shown, the lower end plate 354 can include a first recess 362 formed by a pair of first shoulder members 364. This shoulder member 364 consists of a support leaf spring 356 that creates an axial gap between the leaf spring 356 and the recess 362 along the bottom surface of the leaf spring near the outer circumference. Thus, when an axial load is applied to the upper surface of the leaf spring, it can be retracted into the recess toward the recess. The pair of first shoulder members 364 may be formed integrally with the lower end plate 354 or in separate pieces.

In addition, the lower end plate 354 may have a pair of second shoulder members 365 positioned radially outwardly of the first shoulder member over an axial direction of the first shoulder member 364. The second shoulder member 365 holds the spring laterally (ie, in the translational direction) and allows the leaf spring to be centered relative to the first shoulder member 364 and the recess 362 for proper spring bending. It is configured to engage the peripheral edge of the leaf spring 356 to ensure. The second shoulder member 365 may be configured to restrain the leaf spring to prevent all translational movement. However, the second shoulder member 365 can be laterally offset from the leaf spring in at least one direction, allowing the leaf spring to translate in at least one direction. By allowing this translational motion, a teleport axis of rotation is created that more closely mimics the movement of the original intervertebral disc.

The cover plate 360 may be provided to enclose the leaf spring to prevent the leaf spring from axially moving out of engagement with the pair of first and second shoulder members 364. In this embodiment, the cover plate 360 may be attached to the top surface of the pair of second shoulder members 365. The cover plate 360 may be attached to the second shoulder member 365 by any fastening means known in the art, including but not limited to press fits, welding pins, screws, joints, and the like. The cover plate 360 may have an outer circumference of a size adjacent to the outer circumference of the lower end plate 354 and an inner opening 369 that is sized to accommodate the articulation element (described in more detail below). Cover plate 360 inner opening may include an upwardly extending inner edge 367 that may act in combination with a corresponding surface on top end plate 352 to define the articulation of disk 350. In addition, the cover plate may be configured to receive the disc insertion mechanism. 9 illustrates a leaf spring 356 that is a separate element from the lower end plate 354, but in another embodiment shown in FIG. 9A the leaf spring 356 may be integrally formed with the lower end plate 354. Can be.

Leaf spring 356 may be an element such as a spring that bends under axial load to provide shock absorption, bending and compression resistance. The leaf spring 356 may have a uniform thickness or the thickness may vary. In the embodiment shown in Fig. 9, the leaf spring is thicker at the center than at its end, and in the embodiment shown in Fig. 9A the leaf spring is thicker at the end and the center and thinner between the end and the center. So that the leaf spring becomes wavy when viewed from the cross section. The leaf spring can have any thickness suitable to provide the required shock absorption, bending and compression resistance.

Leaf spring 356 may be made of any suitable material known in the art, including, for example, ceramics, composites, polymers or metals such as cobalt-chromium alloys, stainless steels, and titanium alloys.

The articulation cap 358 may be provided in the convex upper articulation surface 368 and the leaf spring-coupled lower projection 370. The joint surface 368 may be configured to form a joint by mating with the mating surface 371 formed on the inner surface of the upper end plate 352. The mating surface 371 may include a concave surface corresponding to the convex surface of the articulation cap 358. Alternatively, the top end plate mating surface 371 may be convex and the top surface of the articulation cap 358 may be concave. The curvature of each articular surface 368 and mating surface 371 may be selected to mimic the movement of the patient's native disk or to provide the appropriate form, amount of joint and / or translational motion as required for a particular procedure. .

The mating surface 371 of the upper end plate 352 is integral with the end plate or formed into individual pieces as already described in other embodiments as shown in FIG. 9A to use any suitable fixing method known in the art. Can be attached to the end plate. When formed into individual pieces, mating surface 371 may comprise a material that is different from the mating surface of the endplate, such as various materials described as suitable for articulation surfaces associated with other embodiments. The mating surface 371 may be recessed into the raised portion 372 of the end plate 352 so that the end plate 352 may be relatively thin without limiting the radius of curvature that may be provided for the concave mating surface 371. Or the mating surface can be made very shallow.

The raised portion 372 of the upper end plate 352 may include a raised surface 374 having a height “h” of the raised surface. The raised face 374 may be configured to engage an upwardly extending inner edge 367 of the leaf spring cover plate 360 that defines the joint of the disk 350 in at least one direction. Alternatively, raised face 374 and upwardly extending inner edge 367 may be configured to define the articulation of the disc in all directions. In one embodiment, raised face 374 and inner edge 367 may be configured to define the articulation of the disc only in a single plane (eg, an average axial plane). Raised face 374 and inner edge 367 may include any combination of structures suitable for providing disk 350 with the desired range of joints in all planes. Thus, the height "h" of the raised face 374 is, for example, the height "h" being smaller on the front and rear sides of the disk 350 and larger on the lateral side of the disk so that the degree of joint in the front-rear direction It can vary in different locations around the disk, as can be controlled. Alternatively, raised face 374 and inner edge 367 may include mating faces, such as flat faces, corresponding curved faces, angled faces, and stepped faces, to control the degree of articulation of the disc in a predetermined direction. Can be.

The bottom surface of the articulation cap 358 may include a protrusion 370 configured and dimensioned to mate with a groove 366 formed on the top surface of the leaf spring 356. Thus, the cap 358 may be retained at least partially in the groove 366. In one embodiment, the groove 366 may be dimensioned the same as or slightly larger than the projection 370, allowing the cap to remain in the translational direction of motion. In other embodiments, the groove may be larger than the protrusion in at least one direction (eg, along the front-rear axial direction), allowing the cap 358 to translate in a direction during operation. By enabling the translational movement, the momentary axis of rotation is provided. This rotation axis of rotation can more naturally simulate the movement of the original intervertebral disc.

Alternatively, the protrusion 370 may be firmly fixed in the groove 366 to not allow translational motion.

Although the grooves and protrusions are shown to generally correspond to the rectangular shape, the protrusions 370 and the grooves 366 are known in the art, including but not limited to round, oval, elliptical, etc. to provide the required translational degrees of freedom. Can take any suitable shape.

In other embodiments shown in FIGS. 9A-9C, the leaf spring 356 may include a support 380, and the cap 358 may have a groove 382 to receive the support 380. The groove 366 and the strut 380 can be dimensioned and configured to allow translation of the cap 358 relative to the lower end plate 354 in at least one direction. When groove 366 and post 380 are configured to allow translation of the cap, cover plate 360 should also be configured so that translation cap 360 does not interfere with cover plate center opening 369.

The upper end plate 352 may include a recess 384 that receives the articulation insert 386, the insert being recessed to form a joint connection with the convex articulation 368 of the cap 358. 385). As noted above, providing the concave articulation insert 384 does not affect the material of the end plate 352 or affect the design or installation of other components of the disc 350 without the physician including the articulation surface. It can be quite flexible in choosing an appropriate material. Accordingly, insert 384 may be formed of any suitable material known in the art, including but not limited to polymers including rigid polymers such as PEEK or UHMWPE, ceramics, composites or any combination thereof. Can be.

When the articulation insert 386 is provided, the recess 384 in the upper end plate 352 may include a surface configured to hold the insert 386. The recess includes a radial ridge configured to fit into a corresponding radial groove in the insert, such that the insert can snap into the recess. Alternatively, the insert can be attached to the recess by press fit using an adhesive or any combination of adhesives.

In alternative embodiments, disk 350 may also include rigid recovery features such as elastic membranes, elastomer rings, bellows, springs, or fluids, as described above with respect to other embodiments. As described above with respect to other embodiments, disk 350 may include additional shock absorbing features.

In addition, as described in the above embodiments, the articulated surface of the disc 350 reduces similar wear, such as surface polishes or diamond finishes, TiNi finishes, to minimize wear, reduce particulate generation, and increase disc life. May include a finish.

The disk 350 end plate may have a movement preventing structure provided on at least one or both outer surfaces of the end plate to prevent movement, removal, and detachment of the end plate within and from the end of the adjacent spine. The anti-moving structure includes flaps, spikes, teeth, pins, deployable spikes, deployable teeth, flexible teeth, other shaped teeth, insertable or expandable pins, screws, hooks, teeth, ribs and textures. Including but not limited to surfaces.

In addition, the upper and lower end plates of disk 350 may also be coated with bone growth inducing or guiding material to promote bone growth and permanently secure the disk to adjacent vertebrae. In contrast, the upper and lower end plates are rough, porous; Having a laser treated end plate layer; A bone guide / bone guide skeleton; Or with or may be formed from an integral bone guide / bone guide material to promote bone growth.

When the disc 350 is implanted, depending on the location of the spine, the disc 350 is intended to restore height, spinal lordosis and stiffness, provide compressive strength, mimic natural intervertebral discs, or is necessary for a particular process. Enable range of motion.

As a result of the material, shape, and elements used, the disk 350 is capable of bending / extending, lateral bending, axial rotation and displacement depending on the mounting state imparted on the intervertebral disc.

Referring to Figure 10, an exemplary mounting process is disclosed. Generally disc 350 may include an upper end plate 402, a lower end plate 404, a core mechanism 406, the core mechanism being any spring, slotted core, ring spring, leaf spring, coil spring, Elastomer, filled fluid or the articulated disc described above. The intervertebral disc 400 can be implanted in a modular fashion, for example, the end plates 402, 404 of the disc 400 can be inserted into the intervertebral cavity using instruments such as dilators and / or retention mechanisms. The intervertebral space can be expanded using standard spinal dilators that engage the endplates. The test spacer can then be used to determine the appropriate size of the core instrument and insert it into the created disk space. In an exemplary embodiment, the core mechanism 406 is inserted and attached to the end plates 402, 404 using dovetails, slots, or similar connections. This modular insertion technique can prevent excessively widening of the intervertebral space that can damage surrounding tissues and / or blood vessels.

Alternatively, the intervertebral disc 400 can be inserted and preassembled with the use of a particular insertion tool. For example, the endplate retaining clip may be used to be held and fixed in parallel and spaced apart relationships when the endplates 402 and 404 are inserted into the intervertebral space. Once implanted, the clip can be removed and removed from the end plates 402, 404. The clip is then removed from the intervertebral space. In addition, the disk 400 is implanted in a compressed state to prevent excessive expansion. Induction of the disk 400 in the compressed state may be performed by a surgical insertion instrument or an internal instrument located within the disk 400.

Anterior, lateral or anterior lateral surgical methods may be used in the intervertebral disc 400. In addition, according to the intervertebral disc 400 to be implanted, a surgical method or a simultaneous expansion and transplant surgery method with minimal invasion may be used. Simultaneous expansion and implantation can be performed using, for example, a slot formed in the outer surface of the end plates 402, 404 to guide the implant down the dilator during implantation. Also, depending on the intervertebral disc being implanted, anterior longitudinal ligament or natural anterior ligament may be attached directly to the disc or to the spinal body adjacent to the disc. All ligament attachment helps to prevent the movement, removal and detachment of the implant. To aid in implantation of the intervertebral disc, the intervertebral disc may include alignment marks.

While various descriptions of the invention have been described above, it will be appreciated that they may be used singly or in combination of various features. Thus, the invention is not limited to the specific preferred embodiments described herein.

In addition, it should be understood that changes and modifications within the spirit and scope of the present invention are possible to those skilled in the art. For example, some of the implants disclosed herein may be formed from bone, such as taga transplantation, autologous transplantation, and xenograft, and may be partially or completely desalted. In addition, some implants may include bone material or other bone growth inducing material on or within or at its endplates. Such material inside may interact with surrounding anatomical tissue, such as channels or other holes formed in the implant wall. In addition, internal and postoperative alignment marks can be used to assist in the implantation of the intervertebral discs. In addition, the intervertebral disc may be manufactured to have rigidity in situations where dissolution is required. The intervertebral disc can be made rigid by, for example, dissolution between end plates, insertion of spacers between end plates or injection of solidifying liquid between end plates. Accordingly, all simple changes which are easily made by those skilled in the art from the disclosure of the present specification within the spirit and scope of the present invention are included in the present invention together with the embodiments of the present invention. Accordingly, the scope of the invention is defined by the description of the appended claims.

Claims (148)

An intervertebral disc located between the first and second vertebrae, An upper end plate having a first inner surface and a first outer surface, the first outer surface configured to abut the first spine, An upper end plate having a second inner surface and a second outer surface, the second outer surface configured to abut the second spine, A membrane extending between the upper and lower end plates, At least one elastic member disposed between the upper and lower end plates, The resilient member associated with at least one arcuate surface member is configured to be articulated in at least one socket associated with at least one end plate. The recess of claim 1, wherein the at least one elastic member further comprises a first end and a second end, the first end being associated with the arcuate surface member, and the second end being formed in the inner surface of one of the end plates. Intervertebral discs disposed within. 3. The intervertebral disc according to claim 1 or 2, wherein at least one arcuate surface member is secured in a recess formed in an inner surface of one of the end plates. The intervertebral disc as claimed in claim 1, wherein the at least one elastic member further comprises a first end and a second end, each end further connected to a separate arcuate surface member. The intervertebral disc of claim 1, wherein the at least one arcuate member and the resilient member are configured to allow translational movement between the upper and lower end plates. The intervertebral disc according to any one of claims 1 to 5, wherein the at least one elastic member includes at least one first elastic member and a plurality of second elastic members. 7. The intervertebral disc of claim 6, wherein the at least one first elastic member has a first spring constant, the at least one second elastic member has a second spring constant, and the first and second spring constants are not substantially the same. . 8. The intervertebral disc of claim 7, wherein the first spring constant is substantially greater than the second spring constant. 9. The intervertebral disc of claim 8, further comprising a third elastic member, wherein the second and third elastic members are disposed closer to the peripheral edge of the disk than the first elastic member. The method of claim 6, wherein the first elastic member and the plurality of second elastic members are each connected to at least one respective arcuate surface member configured to be articulated in a corresponding respective socket formed on an inner surface of one of the end plates. Attached disc. The intervertebral disc according to claim 1, further comprising at least one elastomeric pedestal disposed between the upper and lower end plates. The method of claim 1, further comprising a casing member disposed adjacent to the at least one elastic member, the casing member defining an articulated surface configured to engage an arcuate surface member associated with the elastic member. Having intervertebral discs. The intervertebral disc according to any one of claims 1 to 12, wherein the elastic member and the arcuate surface member are integrally formed. 14. The intervertebral disc according to any one of the preceding claims, further comprising a membrane disposed between the upper and lower end plates, wherein the membrane encapsulates at least a portion of the at least one elastic member. The intervertebral disc according to any one of claims 1 to 14, wherein the membrane encapsulates the upper and lower end plates. The intervertebral disc according to claim 1, wherein the membrane is formed of an elastomeric material. The intervertebral disc according to claim 1, wherein the membrane comprises a bellows. 18. The intervertebral disc according to any one of the preceding claims, wherein the end plates and the membrane define an interior volume and the volume is at least partially filled with a fluid. 19. The intervertebral disc of claim 18, further comprising a valve in communication with the volume to at least partially fill the volume with a fluid. 20. The intervertebral disc of claim 18 or 19, wherein the fluid is compressible. 20. The intervertebral disc of claim 18 or 19, wherein the fluid is incompressible. 22. The intervertebral disc according to any one of claims 18 to 21, wherein the membrane is at least semipermeable. 23. The intervertebral disc according to any one of claims 18 to 22, wherein the membrane is impermeable. The intervertebral disc according to claim 1, wherein at least one of the end plates is formed of a material selected from the group consisting of metals, polymers, ceramics and composites. The method of claim 1, wherein at least one of the end plates is cortical bone, spongy bone, allograft bone, autografted bone, xenograft bone, desalted or partially desalted. An intervertebral disc formed of bone material selected from the group consisting of bones. 26. The intervertebral disc according to any one of the preceding claims, further comprising a migration-resistant structure disposed on at least one of the first and second outer surfaces. 27. The intervertebral disc according to any one of the preceding claims, further comprising permanent securing means disposed on at least one of the first and second outer surfaces. 28. The intervertebral disc according to any one of the preceding claims, further comprising an implant device attachment, guide, or retention structure disposed on at least one of the first and second end plates. An intervertebral disc for placement between the first and second vertebrae, A first end plate having a first inner surface and a first outer surface in contact with the first vertebra; A second end plate having a second inner surface and a second outer surface in contact with the second vertebra; A membrane extending between the first and second end plates, At least one leaf spring disposed between the end plates and having first and second ends, A first end is attached to the first end plate, and the second end is shaped to be able to move laterally along the inner surface of the first end plate in response to the force of the rib spring. 30. The intervertebral disc of claim 29, wherein the second end of the leaf spring further comprises a roller shaped to allow the second end to roll along the inner surface of the first end plate in response to the force of the rib spring. 31. The intervertebral disc according to claim 29 or 30, wherein the second end further comprises an axle for pivotally mounting the roller. 32. The intervertebral disc of claim 31, wherein the roller comprises a rounded end. 33. The leaf spring of any of claims 29 to 32 wherein the leaf spring further comprises an intermediate portion disposed between the first and second ends, the intermediate portion having an articular surface shaped to mate with an interior surface of the second end plate. Having intervertebral discs. The intervertebral disc of claim 33, wherein the inner surface of the second end plate further comprises an articular surface shaped to mate with the articular surface of the middle portion of the leaf spring. 34. The intervertebral disc of claim 33, wherein the inner surface of the second end plate further comprises a pad shaped to mate with the articular surface of the middle portion of the leaf spring. 36. The intervertebral disc according to any one of claims 29 to 35, further comprising a membrane disposed between the upper and lower end plates, wherein the membrane coats the leaf springs. 37. The intervertebral disc according to any one of claims 29 to 36, wherein the membrane coats the upper and lower end plates. 38. The intervertebral disc according to any one of claims 29 to 37, wherein the membrane is formed of an elastomeric material. 39. The intervertebral disc according to any one of claims 29 to 38, wherein the membrane comprises a bellows. 40. The intervertebral disc according to any one of claims 29 to 39, wherein the end plate and the membrane define an interior volume and the volume is at least partially filled with a fluid. 41. The intervertebral disc of claim 40, further comprising a valve in communication with the volume to at least partially fill the volume with a fluid. 43. The intervertebral disc of claim 40 or 41, wherein the fluid is compressible. 43. The intervertebral disc of claim 40 or 41, wherein the fluid is incompressible. The intervertebral disc according to any one of claims 40 to 43, wherein the membrane is at least semipermeable. 44. The intervertebral disc according to any one of claims 40 to 43, wherein the membrane is impermeable. 46. The intervertebral disc according to any one of claims 29 to 45, wherein at least one of the end plates is formed of a material selected from the group consisting of metals, polymers, ceramics and composites. 47. The method of any one of claims 29-46, wherein at least one of the end plates is cortical bone, spongy bone, allograft bone, autografted bone, xenografted bone, desalted or partially desalted. Intervertebral discs formed from bone material selected from the group consisting of bones. 48. The intervertebral disc according to any one of claims 29 to 47, further comprising a transition prevention structure disposed on at least one of the first and second outer surfaces. 49. The intervertebral disc according to any one of claims 29 to 48, further comprising permanent securing means disposed on at least one of the first and second outer surfaces. The method of claim 29, wherein at least one of the end plates is cortical bone, spongy bone, allografted bone, autografted bone, xenografted bone, desalted or partially desalted. An intervertebral disc formed of bone material selected from the group consisting of bones. An intervertebral disc for placement between the first and second vertebrae, A first end plate having a first inner surface and a first outer surface in contact with the first vertebra; A second end plate having a second inner surface and a second outer surface in contact with the second vertebra; A membrane extending between the first and second end plates, A joint member disposed between the first end plate and the second end plate, the joint member having first and second surfaces; A shock absorbing element disposed between the second surface and one of the end plates, The intervertebral disc is shaped to mate with a first surface of the at least one end plate. 52. The intervertebral disc of claim 51, wherein the inner surface of one of the end plates further comprises an articular surface shaped to mate with the articulation member. 53. The intervertebral disc of claim 51 or 52, wherein the articular surface further comprises articulation pads. 54. The method of any one of claims 51 to 53, further comprising a recess shaped to receive at least a portion of the articulation pad, wherein the recess causes the articulation pad to translate in at least one direction relative to the articular surface. Intervertebral discs shaped to allow. 55. The intervertebral disc according to any one of claims 51 to 54, further comprising a membrane disposed between the upper and lower end plates, wherein the membrane coats the joint member. The intervertebral disc according to any one of claims 51 to 55, wherein the membrane coats the first and second end plates. 57. The intervertebral disc according to any one of claims 51 to 56, wherein the membrane is formed of an elastomeric material. 58. The intervertebral disc according to any one of claims 51 to 57, wherein the membrane comprises a bellows, the bellows at least coating the shock absorbing element. 59. The intervertebral disc according to any one of claims 51 to 58, wherein the end plate and the membrane define an interior volume and the volume is at least partially filled with a fluid. 60. The intervertebral disc of claim 59, further comprising a valve in communication with the volume to at least partially fill the volume with a fluid. 60. The intervertebral disc of claim 59, wherein the fluid is compressible. 61. The intervertebral disc of claim 59 or 60, wherein the fluid is incompressible. 61. The intervertebral disc of claim 59 or 60, wherein the membrane is at least semipermeable. 61. The intervertebral disc of claim 59 or 60, wherein the membrane is impermeable. 52. The intervertebral disc of claim 51, wherein at least one of the end plates is formed of a material selected from the group consisting of metals, polymers, ceramics, and composites. 66. The method of any one of claims 51-65, wherein at least one of the end plates is cortical bone, spongy bone, allograft bone, autografted bone, xenografted bone, desalted or partially desalted. An intervertebral disc formed of bone material selected from the group consisting of bones.  67. The intervertebral disc according to any one of claims 51 to 66, further comprising a migration-resistant structure disposed on at least one of the first and second outer surfaces.  68. The intervertebral disc according to any one of claims 51 to 67, further comprising permanent securing means disposed on at least one of the first and second outer surfaces.  69. The intervertebral disc according to any one of claims 51 to 68, further comprising an implant device attachment, guide, or retention structure disposed on either of the first and second inner and / or outer surfaces.  Intervertebral disc for placement between the first and second vertebrae, A first end plate having a first inner surface and a first outer surface in contact with the first spine; A second end plate having a second inner surface and a second outer surface in contact with the second spine; A second surface comprising a first surface configured to mate with a pocket formed on an inner surface of the first end plate and a joint surface configured to mate with a corresponding surface associated with the second end plate, disposed between the first and second end plates Intervertebral discs comprising slot cores.  71. The intervertebral disc of claim 70, wherein the slot core first surface has a first diameter and the pocket has a second diameter greater than the first diameter such that the slot core can translate within the pocket.  72. The intervertebral disc of claim 70 or 71, further comprising a lead disposed between the first and second end plates and configured to engage the slot core and at least a portion of the pocket to axially retain the core in the pocket.  73. The intervertebral disc according to any one of claims 70 to 72, wherein the second surface of the slot core is configured to be articulated within the second end plate corresponding surface.  74. The intervertebral disc according to any one of claims 70 to 73, further comprising a membrane disposed between the upper and lower end plates to coat at least the slot core and the pocket.  75. The intervertebral disc of claim 74, wherein the membrane further coats the upper and lower end plates.  75. The intervertebral disc of claim 74, wherein the membrane is formed of an elastomeric material.  77. The intervertebral disc according to any one of claims 74 to 76, wherein the membrane comprises a bellows.  78. The intervertebral disc of claim 74, wherein the end plate and the membrane form an interior volume that is at least partially filled with a fluid.  79. The intervertebral disc of claim 78, further comprising a valve in communication with the volume to at least partially fill the volume with a fluid.  80. The intervertebral disc of claim 78 or 79, wherein the fluid is compressible.  80. The intervertebral disc of claim 78 or 79, wherein the fluid is incompressible.  82. The intervertebral disc of claim 70, wherein at least one of the end plates is formed from a material selected from the group consisting of metals, polymers, ceramics, and composites.  84. The method of any one of claims 70-82, wherein at least one of the end plates is cortical bone, spongy bone, allografted bone, autografted bone, xenograft bone, desalted bone or partially degone An intervertebral disc formed of bone material selected from the group consisting of chlorinated bones.  84. The intervertebral disc according to any one of claims 70 to 83, further comprising a movement preventing structure disposed on at least one of the first and second outer surfaces.  85. The intervertebral disc according to any one of claims 70 to 84, further comprising permanent securing means disposed on at least one of the first and second outer surfaces.  86. The intervertebral disc according to any one of claims 70 to 85, further comprising an implant device attachment, guide or retention structure disposed on at least one of the first and second inner or outer surfaces.  Intervertebral disc for placement between the first and second vertebrae, A first end plate having a first inner surface and a first outer surface in contact with the first spine, A second end plate having a second inner surface and a second outer surface in contact with the second spine; A cap having an upper surface and a lower surface configured to mate with an inner surface of the first longitudinal plate, An intervertebral disc comprising a ring spring disposed between an inner surface of a second end plate and a bottom surface of a cap.  88. The intervertebral plate of claim 87, wherein the ring spring has a first surface configured to mate to the bottom of the cap and a second surface configured to mate to a pocket formed on the inner surface of the second end plate.  89. The compression spring of claim 87 or 88, further comprising a slot defining a gap between the first and second end faces of the ring spring, the gap being sized so that the ring spring is elastically compressed. Intervertebral discs, in which the end faces approach each other when positioned.  90. The ring spring of any of claims 87-89, wherein the ring spring further comprises a first diameter, and the bottom of the cap has an axial protrusion comprising a second diameter, the first diameter being generally greater than the second diameter. And an intervertebral disc with which the cap can translate relative to the ring spring when the bottom of the cap engages the upper first surface of the ring spring.  91. The apparatus of any one of claims 87-90, further comprising a plurality of slots disposed between the first and second surfaces, wherein the slot is at least a portion of the ring spring when a compressive force is positioned over the ring spring by the cap. The intervertebral disc which operates to be elastically compressible.  92. The intervertebral disc of claim 91, wherein the protrusion comprises a radial lip having an outer diameter greater than the first diameter of the ring spring, wherein the lip projection is press fit into the ring spring first diameter.  92. The device of any of claims 87-92, disposed between the first and second end plates and configured to engage at least a portion of the pocket with the ring spring or cap to retain the ring spring and the cap axially in the pocket. Intervertebral discs containing more leads.  94. The intervertebral disc according to any one of claims 87 to 93, further comprising a membrane disposed between the upper and lower end plates.  95. The intervertebral disc according to any one of claims 87 to 94, further comprising a membrane disposed between the upper and lower end plates and coating at least a cap, a ring spring, and a pocket.  97. The intervertebral disc of claim 95, wherein the membrane coats the upper and lower end plates.  98. The intervertebral disc of claim 95 or 96, wherein the membrane is formed of an elastomeric material.  98. The intervertebral disc according to any one of claims 95 to 97, wherein the membrane comprises a bellows.  99. The intervertebral disc according to any one of claims 95 to 98, wherein the end plate and the membrane form an interior volume that is at least partially filled with a fluid.  103. The intervertebral disc of claim 99, further comprising a valve in communication with the volume to partially fill the volume with a fluid.  101. The intervertebral disc of claim 99 or 100, wherein the fluid is incompressible.  101. The intervertebral disc of claim 99 or 100, wherein the fluid is compressible.  103. The intervertebral disc according to any one of claims 87 to 102, wherein at least one of the end plates is formed of a material selected from the group consisting of metals, polymers, ceramics and composites.  103. The method of any one of claims 87-103, wherein at least one of the end plates is cortical bone, spongy bone, allografted bone, autografted bone, xenograft bone, desalted bone or partially degone. An intervertebral disc formed of bone material selected from the group consisting of chlorinated bones.  105. The intervertebral disc according to any one of claims 87 to 104, further comprising a movement preventing structure disposed on at least one of the first and second outer surfaces.   105. The intervertebral disc according to any one of claims 87 to 105, further comprising permanent fixation means disposed over the first and second outer surfaces.  108. The intervertebral disc as claimed in any of claims 87 to 106, further comprising an implant device attachment, guide, or retention structure disposed on either the first and second inner or outer surfaces.  An intervertebral disc positioned between the first and second vertebrae, A first end plate having a first inner surface and a first outer surface in contact with the first spine; A second end plate having a second inner surface and a second outer surface in contact with the second spine; An intervertebral disc including a leaf spring further comprising a central body having a first surface and a second elastic end and a length and configured to engage a second end plate and having a first surface and a second surface comprising an articulation surface.  109. The method of claim 108, wherein the second end plate further comprises a recess having a length less than the leaf spring length, wherein the leaf spring is engaged with the second end plate such that the first and second resilient ends are supported on the inner surface of the end plate and the central body is closed. And, when positioned beyond the end plate recess, at least a portion of the central body is movable into the recess when compressive force is applied to the leaf spring first surface such that the second surface contacts the recess surface. 109. The leaf spring of claim 108 or 109, wherein the recess further comprises a recess face, wherein the leaf spring second face and the recess face are configured to form a gap therebetween, so that a predetermined compressive force is applied to the leaf spring first face. The intervertebral disc, when the leaf spring second face is in contact with at least a portion of the recess face. 117. The intervertebral disc of claim 109 or 110, wherein the central body and the recess are configured such that the leaf spring can translate in at least one direction with respect to the second end plate. 117. The intervertebral disc according to any one of claims 108 to 111, wherein the first end plate further comprises an inner surface having an articulation surface configured to correspond to the leaf spring articulation surface. 124. The intervertebral disc of claim 112, wherein the articulation surface is configured to allow the leaf spring to articulate and translate relative to the first end plate. 115. The intervertebral disc according to any one of claims 108 to 113, further comprising a membrane disposed between the first end plate and the second end plate. 117. The intervertebral disc of claim 114, further comprising a membrane disposed between the upper and lower end plates, the membrane surrounding at least the leaf spring. 117. The intervertebral disc of claim 114 or 115, wherein the membrane surrounds the first end plate and the second end plate. 117. The intervertebral disc of claim 114, wherein the membrane is formed of an elastomeric material. 117. The intervertebral disc according to any one of claims 114 to 117, wherein the membrane comprises a bellows. 119. The intervertebral disc according to any one of claims 114 to 118, wherein the end plate and the membrane form an interior space, wherein the space is at least partially filled with fluid. 119. The intervertebral disc of claim 119, further comprising a valve in communication with said space for at least partially filling said space with fluid. 121. The intervertebral disc of claim 119 or 120, wherein the fluid is incompressible. 121. The intervertebral disc according to any one of claims 108 to 121, wherein at least one of the end plates is formed of a material selected from the group consisting of metals, polymers, ceramics and composites. 124. The bone material of any of claims 108-122, wherein at least one of the end plates is a bone material selected from the group consisting of cortex, reticular tissue, taga transplantation, autologous transplantation, xenograft, demineralized or partially demineralized bone. Intervertebral discs formed. 124. The intervertebral disc according to any one of claims 108 to 123, further comprising a movement preventing structure disposed on at least one of the first outer surface and the second outer surface. 124. The intervertebral disc according to any one of claims 108 to 124, further comprising permanent securing means disposed on at least one of the first outer surface and the second outer surface. 124. The intervertebral disc of any of claims 108-125, further comprising an implant instrument attachment, guide, or retention structure disposed on at least one of the first and second inner or outer surfaces. An intervertebral disc for placement between the first and second vertebrae, A first end plate having a first inner surface and a first outer surface configured to contact the first spine, A second end plate having a second inner surface and a second outer surface configured to contact the second spine, A first articulation member having a first face associated with the first end plate, A leaf spring having at least a first face associated with the second end plate and a second face associated with the second face of the first articulating member, The first articulating member is configured to allow the first and second end plates to be articulated relative to each other, and the leaf spring is configured to allow the end plates to approach each other in response to a compressive force applied to at least one of the end plates. 127. The method of claim 127, wherein at least one of the inner surface of the first end plate and the first side of the first articulation member comprises a concave surface, the other side is convex, wherein the surfaces are articulated with the articulation member relative to the first end plate. Intervertebral discs configured to allow. 129. The intervertebral disc of claim 127 or 128, wherein the inner surface of the first end plate is concave and the first joint member is of a corresponding convex shape. 133. The method of any one of claims 127-129, further comprising a second articulation member having a first face associated with the inner surface of the first end plate and a second face associated with the first face of the first articulation member. Intervertebral discs. 133. The intervertebral disc of claim 130, wherein the second face of the second articulation member is concave and configured to correspond to the convex first face of the first articulation member. 143. The intervertebral disc of claim 131, wherein the concave and convex surfaces are configured to allow both articulation and translation between the joint members. 134. The intervertebral disc according to any one of claims 130 to 132, wherein at least one of the joint members is made of a material different from the material of one of the first or second end plates. 137. The intervertebral disc of any of claims 127-133, wherein the inner surface of the first end plate and the first side of the articulation member are further configured to allow the joint member to translate relative to the first end plate. 138. The plate of any of claims 127-134, wherein the second end plate further comprises a recess in the second inner surface, the leaf spring having at least opposite ends of the leaf spring supported by the inner surface and the central portion of the leaf spring being retracted. An intervertebral disc having a length sufficient to span the recess so as to be positioned over the recess, the central portion being movable into the recess when compressive force is applied to the second face of the leaf spring. 137. The intervertebral disc of claim 135, wherein the second end plate further comprises a perimeter having a size and configuration that allows the leaf spring to translate relative to the second end plate in at least one direction. 136. The intervertebral disc of claim 135 or 136, wherein the second end plate further comprises a perimeter having a size and configuration that prevents the leaf spring from translating in at least one other direction. 138. The intervertebral disc of any of claims 134-137, wherein the second face of the leaf spring further comprises a recess configured to receive a protrusion formed on the second face of the articulating member. 138. The intervertebral disc of claim 138, wherein the recess and protrusion are sized and configured to allow the articulating member to translate in at least one direction with respect to the leaf spring. 140. The cap member of any one of claims 136-139, wherein the cap member is configured to engage at least a portion of the second end plate and to cover the at least a portion of the leaf spring to prevent the leaf spring from axially separating from the second end plate. Intervertebral discs, including more. 141. The at least one ridge of any of claims 135 to 140, wherein the cap member is configured to contact at least one raised ridge associated with the first end plate to limit articulation between the end plates in at least one direction. Intervertebral disc further including ridge. 141. The intervertebral disc of claim 141, wherein the raised ridge has a corresponding flat surface profile. 141. The intervertebral disc of claim 141 or 142, wherein the raised ridges have correspondingly inclined surfaces. 143. The intervertebral disc of claim 127, wherein at least one of the end plates is formed of a material selected from the group consisting of metals, polymers, ceramics, and composites. 145. The bone material of claim 127, wherein at least one of the end plates is a bone material selected from the group consisting of cortex, reticular tissue, taga transplantation, autologous transplantation, xenograft, demineralized or partially demineralized bone. Intervertebral discs formed. 145. The intervertebral disc of any of claims 127-145, further comprising a movement preventing structure disposed on at least one of the first outer surface and the second outer surface. 145. The intervertebral disc according to any one of claims 127 to 146, further comprising permanent fixation means disposed on at least one of the first outer surface and the second outer surface. 148. The intervertebral disc of any of claims 127-147, further comprising an implant instrument attachment, guide, or retention structure disposed on at least one of the first and second inner or outer surfaces.

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