Abstract: The invention concerns an implant comprising a body with an upper surface and a lower surface capable of pressing on the vertebral end-plate located immediately above and beneath and having further at least a through aperture emerging on the upper and lower surfaces. The invention is characterized in that the implant further comprises an anchoring member mounted in such a way as to be capable of moving in the aperture. The said anchoring member includes a support part adjacent to a first vertebral end-plate, and at least a projecting anchoring element extending from the support part towards the opposite vertebral end-plate. Thus, when the implant is compressed between the vertebral end-plates, the anchoring member is stressed by the first vertebral end-plate at the support part to move relative to the body and the at least providing projecting element overlaps the body surface facing the opposite vertebral end-plate and is anchored therein.

Abstract: A prosthesis in the form of a cage having opposed complimentary bearing surface assemblies. The bearing surface assemblies moveable towards and away from each other. The moving mechanism being part of the bearing surface assemblies. Each of the bearing surface assemblies having an outer bearing surface whereby movement of one bearing surface assembly in one direction will move the bearing surface assemblies away from each other and movement in the opposite direction will move the bearing surface assemblies towards each other.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by at least one spring mechanism. The preferred spring mechanism is at least one spirally slotted belleville washer having radially spaced concentric grooves. In a preferred embodiment there is a single such belleville washer which is modified to mount onto a ball-shaped head. The lower plate of this embodiment includes a post extending upwardly from the inner surface of the plate, the post including a ball-shaped head. The modified belleville washer can be rotatably mounted to the head such that the wider portion of the washer seats against the upper plate.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by at least one spring mechanism. The preferred spring mechanism is at least one spirally slotted belleville washer having radially extending grooves. In a preferred embodiment there is a single such belleville washer which is modified to mount onto a ball-shaped head. The lower plate of this embodiment includes a post extending upwardly from the inner surface of the plate, the post including a ball-shaped head. The modified belleville washer can be rotatably mounted to the head such that the wider portion of the washer seats against the upper plate.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by at least one spring mechanism. A first plate of this embodiment includes a post extending upwardly from the inner surface of the plate, the post including a ball-shaped head. The post is designed to flexibly support a slotted belleville washer, which can be selectively mounted to the head such that the wider portion of the washer seats against the second plate. Compression of the assembly causes a deflection of the slotted belleville washer. The slotted belleville washer of this invention has a radially varying thickness which permits the load deflection profile to mimic that of the natural cartilage which is being replaced.

Abstract: An intervertebral spacer having opposing plates seatable against opposing vertebral bones, separated by at least one spring mechanism, preferably a spirally slotted belleville washer having a wide end rigidly fixed to an upper plate and a narrow end rotatably mounted to a lower plate. The lower plate includes an inwardly deflecting central post extending upwardly from the inner surface of the lower plate, the post including a head that is received through a central opening in the narrow end of the washer so that the washer is restricted from angulation with respect to the lower plate, but allowed to rotate with respect to the lower plate so that the plates can rotate relative to one another. The plates can angulate relative to one another because the washer deflects under lateral deflection forces and return to its undeflected shape when the forces are relieved.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by at least one spring mechanism. A first plate of this embodiment includes a post extending upwardly from the inner surface of the plate, the post including a ball-shaped head. The post is designed to flexibly support a belleville washer, which can be selectively mounted to the head such that the wider portion of the washer seats against the second plate. Compression of the assembly causes a deflection of the belleville washer. The belleville washer of this invention has a radially varying thickness which permits the load deflection profile to mimic that of the natural cartilage which is being replaced.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by at least one spring mechanism. The preferred spring mechanism is at least one belleville washer having radially spaced concentric grooves. In a preferred embodiment there is a single such belleville washer which is modified to mount onto a ball-shaped head. The lower plate of this embodiment includes a post extending upwardly from the inner surface of the plate, the post including a ball-shaped head. The modified belleville washer can be rotatably mounted to the head such that the wider portion of the washer seats against the upper plate.

Abstract: A dynamic bone fusion device for facilitating fusion between bone sections, particularly vertebrae, is selected having certain stiffness to induce specific strain conditions associated with high success rates in bone fusion. Temporary stiffeners that are absorbable by the body may be implemented with the fusion device.

Abstract: An intervertebral prosthesis includes a disc member dimensioned for insertion within an intervertebral space between adjacent vertebrae to replace at least a portion of an intervertebral disc removed therefrom. The disc member has sufficient rigidity to support the adjacent vertebrae in spaced relation, and defines a longitudinal axis extending the height of the disc member and a lateral axis transverse to the longitudinal axis. The disc member includes an exterior wall which has a slit defined therein. The slit defines a longitudinal component of direction and a lateral component of direction. Preferably, the exterior wall includes a plurality of helical slits, adjacent slits being disposed in at least partial overlapping relation to define an overlapping region.

Abstract: Implantable devices useful for creating bony fusion particularly in intervetebral spinal fusion. The device is formed of bone and has an at least partially demineralized portion between two rigid bone portions creating an area of flexibility. In one application, the area of flexibility may be used to move the device between a reduced size insertion configuration and an expanded implanted configuration. In another use, the area of flexibility may be useful to dampen shock applied to the implant. A method is also disclosed for making the implants and inserting the implants into an intervertebral disc space to promote interbody fusion.

Abstract: A disc replacement prosthesis is described which is placed within the intradiscal space vacated by a removed deteriorated disc, and which affords mobility rather than fusion between adjacent vertebral bodies. The prosthesis also protects remaining discs from deterioration by providing a shock absorbing prosthesis portion. Structure is provided that affords resistance to shear force applied to the shock absorbing portion. The prosthesis adheres initially mechanically to the vertebral bodies and adheres through arthrodesis over a period of time.

Abstract: A prosthetic implant for facilitating fusion of adjacent vertebrae includes an implant member dimensioned to be at least partially positioned within an intervertebral space defined between adjacent vertebrae. The implant member includes first and second vertebral engaging plates operatively connected to each other for respectively engaging vertebral end plates of the adjacent vertebrae and having discontinuous surfaces to engage the vertebral end plates and promote bone ingrowth. A displacement member is associated with the engaging plates and is deployable to cause relative movement of the engaging plates to thereby at least laterally displace the engaging plates whereby in a deployed position the engaging plates are in supportive engaged relation with the adjacent vertebrae. The first and second engaging plates are preferably pivotally connected to each other at respective end portions thereof to define a reduced entry profile to facilitate insertion within the intervertebral space.

Abstract: The invention relates to a device for replacing vertebral bones. The device includes an interior hollow body and an exterior hollow body. These hollow bodies can slide into each other coaxially along a central axis and can be moved in relation to one another in the direction of the central axis. The interior hollow body is provided with a catch mechanism on its outer surface. The exterior hollow body includes a hole or bore extending along the central axis. The exterior hollow body also includes at least one elastic element that projects into the bore at its top end. This reduces the diameter of the bore so that the elastic element latches onto the catch mechanism of the interior hollow body, thereby fixing the length of the device in such a way that it is resistant to compression.