An interbody fusion device employs a torque transfer mechanism to transfer torque to a driving mechanism responsible for expansion of the interbody fusion device in a direction non-parallel to a longitudinal axis of the driving mechanism.

An expandable intervertebral cage device includes a first base plate and a second base plate, a distal block with an internal passage that mechanically couples to each base plate, and a proximal block comprising internal threading. The device has exactly two arm assemblies with one on each side. Each arm assembly comprises a first arm mechanically coupled to the first base plate and a second arm mechanically coupled to the second base plate. A screw is arranged partially within the internal threading of the proximal block and passes through the internal passage of the distal block, such that rotation of the screw relative to the distal block causes a change in distance between the distal block and the proximal block, and a corresponding change in the spacing and lordosis of the device.

A surgical instrument includes a chassis, a first driving shaft, a first measuring mechanism, a second measuring mechanism, and a first handle. The chassis defines a first channel and a second channel each extending from a proximal end to a distal end. The first measuring mechanism corresponds to rotation in the first channel. The second measuring mechanism corresponds to rotation in the second channel. The first driving shaft is operable to be inserted into the first channel, engaging with the first measuring mechanism. The first driving shaft has an end portion configured to engage and drive a first adjustable feature and/or a second adjustable feature on a work-piece. The handle is operable to be releasably attached to the first driving shaft for applying torque or operable to remove the first driving shaft from the first channel.

A distally expanding facet joint implant and delivery device for distally distracting a facet joint. The facet joint implant generally includes an outer part and an inner part. The outer part includes a pair of opposed distally expandable facet plates connected by a hinge. The inner part includes a wedge that is selectively movable against the facet plates to distally expand and contract the facet joint implant into open and closed states. Teeth on the outer part engage indents on the inner part to maintain the facet joint implant in the distally expanded state. The outer and inner parts include outer and inner connectors, and the delivery device includes corresponding outer and inner connectors adapted to be in locked engagement with the outer and inner connectors to hold the implant and selectively cause it to distally expand and contract.

An implant for therapeutically separating bones of a joint has two endplates each having an opening through the endplate, and at least one ramped surface on a side opposite a bone engaging side. A frame is slideably connected to the endplates to enable the endplates to move relative to each other at an angle with respect to the longitudinal axis of the implant, in sliding connection with the frame. An actuator screw is rotatably connected to the frame. A carriage forms an open area aligned with the openings in the endplates. The openings in the endplates pass through the carriage to form an unimpeded passage from bone to bone of the joint. The carriage has ramps which mate with the ramped surfaces of the endplates, wherein when the carriage is moved by rotation of the actuator screw, the endplates move closer or farther apart.

An expanding, conforming interbody implant includes a plurality of superior and a plurality of inferior segments. The segments are adapted to individually expand, contact, and conform to endplates of vertebral bodies to distribute forces equally over the implant and across the vertebral endplates. Once a proper extension of the segments has been achieved, the segments are locked in position. The implant has a stiffness that approximates the stiffness of bone, and the implant minimizes problems with subsidence, endplate fractures, and stress shielding.

An elbow prosthesis according to the present teachings can include a stem structure and an articulating component. The stem structure can be operable to be positioned in a bone of a joint. The stem structure can include a stem portion that is operable to be positioned in the bone and a C-shaped body portion having a first retaining mechanism formed thereon. The articulating component can have a second retaining mechanism formed thereon. One of the first and second retaining mechanisms can comprise an extension portion and a first anti-rotation portion. The other retaining mechanism can comprise a receiving portion and a second anti-rotation portion. The articulating component can be advanced from an insertion position to an assembled position, such that the first and second mechanisms cooperatively interlock to inhibit translation and rotation of the articulating component relative to the C-shaped body portion of the stem structure.

An elbow prosthesis includes a stem structure and an articulating component. The stem structure is operable to be positioned in a bone of a joint and includes a stem portion and a C-shaped body portion. The stem portion is operable to be positioned in the bone. The C-shaped body portion includes a first articulating surface bound by a medial wall and a lateral wall. The medial and lateral walls are separated by a first distance. The articulating component includes a second articulating surface positioned between a medial side surface and a lateral side surface. The medial and lateral side surfaces are separated by a second distance that is less than the first distance. The second articulating surface is configured to slidably communicate in a medial/lateral direction along the first articulating surface of the C-shaped body portion.

The present invention relates to a spinal fusion cage which is inserted between vertebral bodies at the lowest height and is height-adjustable in the inserted state, and has improved fixing strength by insertion of a bone screw through an end plate, wherein cages having heights within a predetermined range can be replaced by a single cage. Therefore, manufacturers can reduce the number of product groups that need to be produced, and can also reduce product stock. In addition, unlike the conventional cages having preset heights at regular intervals, the height can be linearly adjusted according to the distance between the vertebral bodies of a patient, and thus surgery can be performed using the cage adjusted to an optimum height according to the patient’s condition.

A tunable implant, system, and method enables a tunable implant to be adjusted within a patient. The tunable implant includes a securing mechanism to secure the implant in the patient, a actuation portion that enables the implant to move and an adjustment portion that permits adjustment of the implant after the implant has been positioned within the patient. The method of adjusting the tunable implant includes analyzing the operation of the implant, determining if any adjustments are necessary and adjusting the implant to improve implant performance. The implant system includes both the tunable implant and a telemetric system that is operable to telemetrically receive data from the tunable implant where the data is used to determine if adjustment of the tunable implant is necessary. The system also includes an instrument assembly that is used for performing spinal surgery where the instrument assembly includes a mounting platform and a jig.