A prosthesis may include a stem, a ball stud, an adaptor, and a head. The stem may include a longitudinal axis and a bore having a central axis that is angled relative to the longitudinal axis. The ball stud may include a cylindrical shaft and a ball end. The cylindrical shaft may be received in the bore of the stem. The adaptor may include a tapered outer surface and a ball socket rotatably receiving the ball end of the stud. The head may be rotatably supported by the adaptor and may include a semispherical articulating surface and a female taper rotatably receiving the tapered outer surface of the adaptor.

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.

A robotic system for preparing a bone to repair a bone fracture, includes a controllable guide structure configured to guide preparation of at least one bone piece during execution of a surgical plan and a control system configured to define the surgical plan. Defining the surgical plan includes determining a desired relationship between at least a first bone piece and a second bone piece that are separated by the bone fracture and planning preparation of the first bone piece to include a prepared anatomical structure configured to align the first bone piece with the second bone piece such that when aligned, the first bone piece and the second bone piece will achieve the desired relationship. The control system is further configured to control the controllable guide structure according to the surgical plan.

Bone structure coupling devices and methods are provided herein. An example method includes positioning a tubular retraction guide body into a patient, the tubular retraction guide body having two prongs that are positioned in a joint between two adjacent bone structures, creating a hemispherical groove on each of the two adjacent bone structures using a drill bit passed through the tubular retraction guide body, incising out the hemispherical grooves with a broach passed through the tubular retraction guide body, and inserting a graft body having a generally rectangular cross sectional area into the angular grooves to couple the two adjacent bone structures together.

A plate and cage assembly for stabilization of vertebral bodies. The assembly includes at least one fixation member, a cage having a proximal wall, a superior surface and an inferior surface (the superior surface and the inferior surface for engaging adjacent vertebrae), and a plate coupled to the cage and having at least one hole traversing the plate at an angle for insertion of the at least one fixation member into one of the vertebral bodies. The proximal wall of the cage has a blind hole, and the plate has a threaded screw hole aligned with the blind hole in the proximal wall of the cage.

An intervertebral implant has a hollow space formed within the implant and accessible through an elongate opening extending through a recessed portion of the side wall, and the hollow space is shaped to receive an engagement portion of a drive shaft of an insertion tool; and the intervertebral implant includes at least two guiding surfaces facing each other and being configured for sliding engagement by a portion of a sleeve of the insertion tool movably holding the drive shaft.

The invention relates to an apparatus for inserting a cage between vertebrae, according to the inventive concept, includes a body accommodating an inner rod coupled to the cage, which is to be inserted between vertebrae, a push bar installed in the body to be slid and configured to push one side of the cage as the push bar is moved forwards from the body, a support bar supporting an opposite side of the cage and installed in the body to be slid to move rearwards when the push bar is moved forwards, and an adjustment unit installed in the body to be manipulated and configured to adjust movements of the push bar and the support bar such that a rotation amount of the cage is adjusted according to manipulation by a user.

An intervertebral implant has a hollow space formed within the implant and accessible through an elongate opening extending through a recessed portion of the side wall, and the hollow space is shaped to receive an engagement portion of a drive shaft of an insertion tool; and the intervertebral implant includes at least two guiding surfaces facing each other and being configured for sliding engagement by a portion of a sleeve of the insertion tool movably holding the drive shaft.

Devices, systems and methods for surgical treatment of mid-foot disorders such as osteoarthritis, spacing disorders, or alignment disorders, including mid-foot arthroplasty devices and systems for the 2.sup.nd and 3.sup.rd tarsometatarsal (TMT) joint, implants for post-osteotomy spacing and realignment, arthroplasty articular implants, dowel grafts for TMT arthrodesis or fusion, dowel grafts for navicular cuneiform (NC) arthrodesis, dowel grafts for intercuneiform arthrodesis, and/or locking dowels for joint fusion.

A unitary intervertebral device, having no moving components is provided for non-fusion articulation and fusion applications. The interbody articulating device allows for limited flexion and rotation between the implant and an adjacent vertebrae, helping to preserve or restore near-normal motion between adjacent vertebrae. Rotational motion is achieved through one or more protrusions incorporated into the spinal interbody device. In one articulating form, a first protrusion extends perpendicularly from one bearing surface of the interbody device to form a rotational protrusion, while at least a second protrusion extends from the opposite bearing surface of the interbody device to form a non-rotational protrusion. In another form, a single protrusion extends axially from one bearing surface of the interbody device to form a spike or anchoring, rotating protrusion, while the opposite bearing surface may be slightly rounded and/or comprising a bone-ingrowth promoting surface. Similarly configured fusion salvage devices are also described.