An ankle arthroplasty system may have a talar prosthesis and a tibial prosthesis, each of which has an articular surface and a bone engagement surface. Each bone engagement surface may have an anterior-posterior curvature and a medial-lateral curvature with a convex shape. A burr with a rotatable cutting element may be used to form a prepared surface on the talus or the tibia to receive the corresponding prosthesis. A cutting guide may be used to guide motion of the burr; the cutting guide may include a base and an arm movably coupled to the base. One of the base and the arm may have a guide surface, and the other may have a follower that slides along the guide surface to constrain motion of the burr such that the prepared surface has at least one concave curvature and one convex curvature.

A kit for preparing an intervertebral disc space for receiving an implant (100) includes a plurality of trials (152) having different sizes. Each trial (152) includes a body (154) insertible into an intervertebral disc space, the body (154) having a leading end (162), a trailing end (164), a top surface (156) and a bottom surface (160), the top surface of the body having a first groove (176) formed therein. Each implant also includes a flange (166) secured to the trailing end (164) of the body (154), the flange (166) having a first channel (180) aligned with the first groove (176), wherein each of the different sized trials has a different flange thickness. The flange thickness controls advancement of a cutting tool such as a chisel (192) into the first groove at the top surface of the trial body, which controls the depth of the cut into vertebral bone.

A total elbow replacement prosthesis (100) comprising: a radioulnar component (20) having an ulnar bearing surface (22) and an anconeal process bearing surface (24), a humeral component (40) having a trochlear bearing surface (42), the trochlear bearing surface being configured for bearing against the ulnar bearing surface, the humeral component further comprising an olecranon aperture boundary bearing surface (50), the anconeal process bearing surface being configured for bearing against the olecranon aperture boundary bearing surface.

Technologies are generally provided for devices, systems, and methods to provide spinal fixation, spinal stabilization, and/or spinal fusion. Example devices may include a first end and a second end with a middle portion extending between the first and second end. The first end may be configured to be in contact with a portion of a first or upper vertebra and the second end may be configured to be in contact with a portion of a second or lower vertebra in an adjacent vertebral pair. Portions of the vertebra which may be in contact with the device may include lamina, processes, vertebral bodies, and facet joints. The example devices may include bone engagement features, such as screws or similar fasteners, to enhance stabilization and fixation when in contact with the vertebrae. Additionally, the devices may include a bone integration feature to promote bone growth and to facilitate fusion between the vertebrae.

This invention improves upon prior art total disc replacements (TDRs) by more closely replicating the kinematics of a natural disc. The preferred embodiments feature two or more fixed centers of rotation (CORs) and an optional variable COR (VCOR) as the artificial disk replacement (ADR) translates from a fixed posterior COR that lies posterior to the COR of the TDR to facilitate normal disc motion. The use of two or more CORs allows more flexion and more extension than permitted by the facet joints and the artificial facet (AF). AF joint-like components may also be incorporated into the design to restrict excessive translation, rotation, and/or lateral bending.

A prosthetic ankle including a talar component and a tibial component. At least a portion of top surface of the talar component has a convex curvature, relative to a location above the top surface, in the anterior to posterior direction as viewed in a sagittal plane cross-section, and a concave curvature relative to a location above the top surface, in the medial to lateral direction. An axis of cone projected based on medial and lateral circles located in medial and lateral sagittal plane cross-sections which approximate the average radius of curvature of the top surface of the talar component as viewed in medial and lateral sagittal plane cross-sections, has a total offset angle from the lateral direction in the range of 0 to 45. In another aspect, the present invention further comprises a bearing component adapted for location between the tibial component and the talar component.

An ankle arthroplasty system may have a talar prosthesis and a tibial prosthesis, each of which has an articular surface and a bone engagement surface. Each bone engagement surface may have an anterior-posterior curvature and a medial-lateral curvature with a convex shape. A burr with a rotatable cutting element may be used to form a prepared surface on the talus or the tibia to receive the corresponding prosthesis. A cutting guide may be used to guide motion of the burr; the cutting guide may include a base and an arm movably coupled to the base. One of the base and the arm may have a guide surface, and the other may have a follower that slides along the guide surface to constrain motion of the burr such that the prepared surface has at least one concave curvature and one convex curvature.

An implant couples a first bone of a hand to a second bone of the hand. The implant includes a body that defines a median plane. The body also defines a first joint surface having a first central region that articulates with the first bone. The body further defines a second joint surface having a second central region that articulates with the second bone, and the second central region is disposed on an opposite side of the median plane of the body relative to the first central region. The first and second central regions correspond to profiles of first and second axial segments, respectively, the first and second axial segments are each one of a cylinder, a cone and a torus and are centered on first and second axes, respectively, and the first and second axes, as projected on the median plane, are substantially perpendicular to each other.

Spacerless artificial disc replacements (ADR) are disclosed. One preferred embodiment includes two saddle-shaped components to facilitate more normal spinal flexion, extension, and lateral bending while limit axial rotation, thereby protecting the facet joints and the annulus fibrosus (AF). Either or both of the superior and inferior components are made of a hard material such as chrome cobalt, titanium, or a ceramic including alumina, zirconia, or calcium phosphate. The articulating surfaces of the ADR are also preferably highly polished to reduce friction between the components. Metals, alloys or other materials with shape-memory characteristics may also prove beneficial.

A kit for preparing an intervertebral disc space for receiving an implant (100) includes a plurality of trials (152) having different sizes. Each trial (152) includes a body (154) insertible into an intervertebral disc space, the body (154) having a leading end (162), a trailing end (164), a top surface (156) and a bottom surface (160), the top surface of the body having a first groove (176) formed therein. Each implant also includes a flange (166) secured to the trailing end (164) of the body (154), the flange (166) having a first channel (180) aligned with the first groove (176), wherein each of the different sized trials has a different flange thickness. The flange thickness controls advancement of a cutting tool such as a chisel (192) into the first groove at the top surface of the trial body, which controls the depth of the cut into vertebral bone.