An intervertebral disc prosthesis is disclosed comprising at least two plates, namely first and second plates, articulated about each other by means of a curved surface, namely articulation, of at least one of the plates, each of the plates comprising a surface known as a contact surface, intended to be in contact with a vertebral plate of one of the vertebrae between which the prosthesis is intended to be inserted, this contact surface for each of the plates comprising a geometrical centre at equal distance from at least two diametrically opposite points located on the periphery of the plate, in which the geometric centres of the plates are not vertically aligned, this off-setting of the geometrical centres of the plates engendering an off-setting of the edges of the plates in at least one direction perpendicular to the vertical axis of the spinal column.

This disclosure relates to intervertebral disc prostheses which may have an upper plate, a lower plate, and a mobile core, with the upper surface of the core being in contact with at least a part of the lower surface of the upper plate. In some configurations, limit stops reduce friction while limiting or preventing the movements of the core relative to the lower plate, in translation and in rotation, respectively, along an axis substantially parallel to the lower plate and about an axis substantially perpendicular to the lower plate. Instrumentation for insertion of the prostheses into intervertebral spaces is also described.

The dynamic implant fixation plate and implant configured to accept the disclosed fixation plate can, in some aspects, provide a means of fixing an implant relative one or more planes while allowing motion relative to one or more planes. The use of the disclosed fixation plate and corresponding implant can reduce the occurrence of stress shielding and permit enhanced loading of the implant site.

An intervertebral prosthetic implant having a first endplate having a first surface configured to substantially engage with a first vertebral body and a second surface having an extension with a concave contact surface, the concave contact surface being spaced apart from the second surface. A second endplate is provided with a first surface configured to substantially engage with a second vertebral body and a second surface comprising a convex contact surface, and the second endplate having a securing element positioned along and above the second surface defining a first and second window on opposing sides of the second surface. The securing element extends along the width and length of the lower endplate and configured with an access hole. An extension portion extends from the first surface of the first endplate through the access hole of the securing element and contacts the second surface of the second endplate.

An intervertebral prosthesis for insertion between adjacent vertebrae includes upper and lower prosthesis plates locatable against respective vertebrae and having opposing, concavely curved recesses therein, and a core located between the plates. The core has opposed, convexly curved surfaces received in the recesses of the plates to allow the plates to slide in articulated manner over the core. The opposed surfaces of the core and the recesses of the plates have cooperating spherical curvatures. The recess of each plate surrounds a locating peg projecting centrally from the base of the recess and is bounded by an annular rim, such that the annular rims of the plates are arranged to contact one another at a predetermined limit of sliding movement of the plates over the core. The peg locates loosely in an opening located centrally in a curved surface of the core, whereby the plates can slide over the core in all directions while the peg holds the core captive.

An artificial joint includes a first joint assembly and a second joint assembly. The first joint assembly is adapted to be connected to a first bone and has a first contacting surface, wherein the first contacting surface includes a first convex arc surface, a second convex arc surface, and a third convex arc surface. The second joint assembly is adapted to be connected to a second bone and has a second contacting surface, wherein the second contacting surface is in contact with the first contacting surface and includes a first concave arc surface, a second concave arc surface, and a third concave arc surface, and the first concave arc surface, the second concave arc surface, and the third concave arc surface respectively correspond to the first convex arc surface, the second convex arc surface, and the third convex arc surface.

A humeral head assembly is provided that includes an articular body and a coupler. The articular body includes a coupling portion disposed on a side of the articular body opposite an articular surface. The coupling portion includes a continuous zone of eccentricity adjustment. The coupler portion optionally includes one or more than one discrete position site. The coupler includes a first portion and a second portion opposite the first portion. The first portion is configured to mate with the coupling portion and the second portion is configured to mate with another member of a joint prosthesis. A coupling portion with the continuous range of eccentricity adjustment can be provided on a bone anchor and the eccentricity of another component can be selected by motion of a coupler, such as a tray for reverse humeral assemblies, along the coupling portion of the anchor.

A knee joint prosthesis is configured to move between an extended position and a flexion position. The knee joint prosthesis includes a femoral component configured to be mounted to a femur, and a tibial component configured to be mounted to a tibia. The tibial component is configured to engage the femoral component to form the knee joint prosthesis. A post is fixedly connected to one of the femoral component and the tibial component, and a cam recess is defined on the other of the femoral component and the tibial component. The cam recess is configured to engage the post in either the extended position or the flexion position of the knee joint prosthesis. An artificial ligament is fixedly connected to the femoral component and the tibial component to simulate either an anterior cruciate ligament or a posterior cruciate ligament.

An intervertebral disc prosthesis is disclosed comprising at least two plates, namely first and second plates, articulated about each other by means of a curved surface, namely articulation, of at least one of the plates, each of the plates comprising a surface known as a contact surface, intended to be in contact with a vertebral plate of one of the vertebrae between which the prosthesis is intended to be inserted, this contact surface for each of the plates comprising a geometrical centre at equal distance from at least two diametrically opposite points located on the periphery of the plate, in which the geometric centres of the plates are not vertically aligned, this off-setting of the geometrical centres of the plates engendering an off-setting of the edges of the plates in at least one direction perpendicular to the vertical axis of the spinal column.

An intervertebral prosthesis for insertion between adjacent vertebrae includes upper and lower prosthesis plates locatable against respective vertebrae and having opposing, concavely curved recesses therein, and a core located between the plates. The core has opposed, convexly curved surfaces received in the recesses of the plates to allow the plates to slide in articulated manner over the core. The opposed surfaces of the core and the recesses of the plates have cooperating spherical curvatures. The recess of each plate surrounds a locating peg projecting centrally from the base of the recess and is bounded by an annular rim, such that the annular rims of the plates are arranged to contact one another at a predetermined limit of sliding movement of the plates over the core. The peg locates loosely in an opening located centrally in a curved surface of the core, whereby the plates can slide over the core in all directions while the peg holds the core captive.