A knee joint prosthesis for a tibia and femur can include a tibial component, a tibial bearing, and a post. The tibial bearing can include a first bearing portion, a second bearing portion, and an aperture. The first bearing portion can be positionable on a first side of the sagittal axis and can have a first shape. The second bearing portion can be positionable on a second side can have a second shape different than the first shape. The post, together with the first bearing portion and the second bearing portion, can be configured to promote the femur to pivot substantially about the first bearing portion.

A knee joint prosthesis system for implantation in a first knee joint of a patient. The first knee joint has a condition. The knee joint prosthesis system includes a tibial baseplate component, a femoral component having a femoral articulation surface, and a tibial insert. The tibial insert includes a tibial articulation surface configured to articulate with the femoral articulation surface. The tibial articulation surface includes a medial tibial compartment asymmetrical to a lateral tibial compartment. The tibial articulation surface is shaped to cooperate with the femoral articulation surface to adapt kinematics of the first knee joint having the condition and the tibial articulation surface is also suitable for implantation in a second knee joint on a second side, the second knee joint lacking the condition.

A knee joint prosthesis is capable of moving between an extended position and a flexion position. The knee joint prosthesis includes a femoral component that is configured to be mounted to a femur, and a tibial component that is configured to be mounted to a tibia. The femoral component and the tibial component are at least partially connected together by a geared arrangement.

According to one example, a bearing component for a knee arthroplasty is disclosed. The bearing component can optionally comprise any one or combination of: a medial compartment having an medial articular surface with a medial articular track and having a first thickness as measured at the medial articular track between the medial articular surface a medial distal surface; and a lateral compartment having a lateral articular surface with a lateral articular track and having a second thickness as measured at the lateral articular track between the lateral articular surface a lateral distal surface; wherein the medial articular surface at the medial articular track and the lateral articular surface at the lateral articular track each have an inclination so as to form an acute angle with respect to a resected proximal surface of a tibia.

A load dissipating arthroplasty prosthesis comprising a shell, an articular device extending into the shell through a collar defined in the sell, a head and neck portion of the articular device extending from the collar, a shaft portion of the articular device extending into the shell, and a plurality of shock absorbing arcuate linkers spacing and allowing limited movement between the shell and the articular device.

Improved ankle prosthesis.

The invention concerns an ankle prosthesis (100), comprising a talar component (200) which includes a talar upper face (201) defining a first articular surface (202) and which extends between a talar anterior edge (203) and an opposite talar posterior edge (204) according to a first average direction, said first articular surface (202) being curved according to said first average direction, said first articular surface (202) comprising a first curved portion (202A) and a second curved portion (202B), each extending according to said first average direction, said first curved portion (202A) having a first curvature and said second curved portion (202B) having a second curvature, said prosthesis (100) being characterized in that said first curved portion (202A) and said second curved portion (202B) define respectively an anterior portion and a posterior portion of said first articular surface (202), said first curvature being greater than said second curvature.

Ankle prostheses.

Implant apparatus and methods directed toward treating conditions involving the knee joint and the patella specifically are disclosed. Full range of motion of the knee joint and tissue integrity are maintained in treatment approaches involving implanting a joint surface load reducing implant proximate the joint to change the direction of the tendons or muscles exerting forces on the joints.

The joint implant of the present invention is fitted into C1-2 lateral joints through the back of the neck instead of oral approach to avoid infections. It is made of 2 inter-digitating components. One part of the joint implant has a circular railing circumference of a circle, the center of which is odontoid, that inter-digitates in a corresponding circular channel of the other part. Two such implants are fixed on both sides of C1-2 joint simultaneously along the circumference. The circular railings provide mainly circular motion in clockwise and anti-clockwise direction. With some degree of play in channel and rail and making the interacting surfaces of the implant convex on convex, provides the gyroscopic motion with lateral and translational movement and also coupling (vertical translation on rotational movement). This gyroscopic design makes it universal and is likely to work in C1-2 joints of every individual with any possible joint orientation.

An endoprosthesis for replacing the ankle joint includes a lower component which is configured to be connected to the ankle bone, an upper component which is configured to be connected to the shin bone, and an intermediate part which forms a slide joint both with the lower and upper components. The intermediate part, which is wedge-shaped in sagittal section, is provided in order to compensate for anatomical or surgical irregularities. The upper component can also be wedge-shaped in frontal or sagittal section.

According to some embodiments of the invention, an intervertebral disc replacement includes a first layer having a lower surface for contacting a first vertebral bone, a second layer coupled to the first layer, the second layer comprising a plurality of compressible column springs, and a third layer coupled to the second layer, the third layer having an upper surface for contacting a second vertebral bone. Each of the plurality of compressible column springs comprises a plurality of stacked coils, and each of the plurality of stacked coils has a spring constant (K). At least one of the plurality of compressible column springs includes a first coil having a first spring constant and a second coil comprising a second spring constant, wherein the first spring constant is different from the second spring constant.