A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

A facet joint replacement system includes an inferior implant with an inferior articular surface, a superior implant with a superior articular surface, and an optional crossbar. The inferior implant and the superior implant are each polyaxially adjustably connected to fixation elements which anchor the implants to adjacent vertebrae. The optional crossbar may be polyaxially adjustably connected to bilateral implants. The system components may be provided in kits which provide components of various sizes and shapes. A set of surgical instruments may facilitate implantation of the facet joint replacement system by providing tools for bone preparation, trialing, implant insertion, implant alignment, and lock-out of modular interconnections.

An apparatus and method is provided for interbody fusion including distracting, in a given direction, and supporting opposing vertebral bodies. A plurality of wafers are consecutively inserted between the vertebral bodies to create a column of wafers. The column of wafers is oriented between the vertebral bodies so as to expand in the given direction as the wafers are consecutively added to the column.

Superior and/or inferior facets of one or more facet joints may be replaced by superior and/or inferior facet joint prostheses. In one embodiment, a kit of superior or inferior prostheses is provided, in which the prostheses have at least two dimensions that vary among members of the kit independently of each other. Each prosthesis may have a bone engaging surface having a surface that is polyaxially rotatable against a corresponding resection of a vertebra. Each prosthesis may also have an articulating surface shaped such that, after attachment to the spine, the replaced or partially replaced facet joints provide a larger medial-lateral range of motion when the spine is flexed than when the spine is extended. Crosslinks may be used to connect left and right prosthesis together in such a manner that they are stabilized in a position in which they are seated directly against the vertebra.

Methods for supporting a prosthetic implant in a patient are disclosed. In some embodiments, a hollow sleeve and a prosthetic implant with a stem component are implanted in a cavity in an end of a bone where the hollow sleeve provides an axial channel that extends through the length of the hollow sleeve for receiving the stem component. In some embodiments, the hollow sleeve is capable of being impacted into the cavity for obtaining a press fit of the hollow sleeve in the cavity. In some embodiments, the hollow sleeve is formed with a porous material.

An expandable interbody device for placement between adjacent vertebrae having an upper structure, a lower structure and a screw mechanism, wherein actuation of the screw mechanism moves the upper and lower structures between a collapsed configuration and an expanded configuration. A deployment tool couples to the expandable interbody device for positioning the device between adjacent vertebrae, actuating the screw mechanism and delivering a material to a chamber of the expandable interbody device.

To provide a sliding member having improved wear resistance, and a method of manufacturing the sliding member. A femoral head ball according to an aspect of the present disclosure includes a composite ceramic containing alumina and at least one oxide other than alumina. A surface roughness Ra of the sliding surface when the femoral head ball slides against a constituent member constituting an artificial joint is not more than 0.01 m. The sliding surface includes a plurality of recessed portions each having an opening diameter of not more than 2 m.

To provide a sliding member having improved wear resistance, and a method of manufacturing the sliding member. A femoral head ball according to an aspect of the present disclosure includes a composite ceramic containing alumina and at least one oxide other than alumina. A surface roughness Ra of the sliding surface when the femoral head ball slides against a constituent member constituting an artificial joint is not more than 0.01 m. The sliding surface includes a plurality of recessed portions each having an opening diameter of not more than 2 m.