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.

A method of performing a computer-assisted surgical procedure on the spine of a patient comprising the steps of: planning, on a computer, a surgical procedure based on at least one of two- and three-dimensional images of the patient's spine; affixing a robotic assembly over an operative region of the patient; determining, with a computer in communication with the robotic assembly, a desired trajectory of a surgical tool along at least one of an access path and an implant path towards the surgical target site; and placing at least a portion of the surgical tool through the aperture along said desired trajectory along at least one of said access path and said implant path towards the surgical target site.

System, including methods and apparatus, for replacing an end of a bone, such as a radial bone, with a prosthesis. In exemplary embodiments, the prosthesis is a radial head prosthesis having a stem portion and a head portion. The head portion may be configured to be (a) placed onto the stem portion by movement of the head and stem portions relative to one another transverse to a longitudinal axis of the stem portion, and then (b) rotated with respect to the stem portion to produce friction that firmly attaches the head portion to the stem portion.

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.

A prosthesis having: a) a first assembly with a first base portion to be placed against, and operatively secured to, a patient's first bone; and b) a second assembly with a second base portion to be placed against, and operatively secured to, a patient's second bone. The first and second assemblies respectively define first and second surfaces that cooperate with each other to guide articulated movement between the first and second bones. At least one of the first and second base portions is configured to cooperate with a separate first component defining at least a part of one of the first and second surfaces to maintain the first component in an operative state. A second component is configured to define at least a part of the one of the first and second surfaces and can be placed in an operative state selectively in place of the first component.

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 implant for use in spinal surgery comprises a resilient element having an inflatable cavity. It is formed of a biologically compatible material and is arranged for placement between end plates of adjacent vertebra. The implant may also include a wound disc replacement element. A method of performing spinal surgery on a patient comprises securely mounting a patient onto a patient support table; imaging a spinal region of the patient; building up a three-dimensional image file of the spinal region of the patient; storing the image file; and utilizing the image file for planning and carrying out computer controlled spinal surgery on the patient utilizing the implant. A computer-controlled surgical implant system comprises a steerable endosurgical implanting assembly operative to install the implant at a desired location in a patient; and a computerized controlled, which operates the steerable endosurgical implanting assembly.

A trial kit for a hinged knee implant system is disclosed. The trial kit includes a tibial base plate trial, an adaptor and a tibial bearing insert trial. The adaptor and insert trial can be assembled and the assembly mounted on the tray trial by sliding the assembly in an anterior-posterior direction on the tray trial. The adaptor has a post with a cross-piece. The insert trial has openings and channels to receive the post and cross-piece. The openings are sized, shaped and oriented so that the cross-piece of the elongate post must be oriented in different directions to pass through the different openings.

A surgical implant with recesses adapted to capture fixation medium that extravasates during implantation. The implant includes an elongated stem having a distal tip configured for insertion into an implant receiving area of a patient. A collar having recesses for capturing extravasating fixation medium is attached on the stem. The collar can be fixed to the stem by a separable collar-engagement feature or the collar can be fixed to the stem via structures on the stem.

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.