An implant (30) for a mammalian bone joint (3) for spacing a first bone (2) of the joint from a second bone (1) of the joint while allowing translational movement of the second bone in relation to the first bone is described. The implant comprises (a) a distal part (31) configured for intramedullary engagement with an end of the second bone, (b) a proximal part (34) having a platform (15) configured for non-engaging abutment of an end of the first bone and translational movement thereon, and (c) an articulating coupling (10, 16) provided between the distal and proximal ends allowing controlled articulation of the first and second bones. The bone-abutting platform is shaped to conform to and translate upon the end of the first bone. A kit for assembly to form the implant of the invention, and the use of the implant to treat osteoarthritis in a bone joint, are also described.

A prosthesis (1) for the trapeze-metacarpal joint of the thumb comprises a body (2) suitable for being arranged between the scaphoid (31) and the metacarpus (30) of the thumb, such body (2) has the shape of an Archimedean solid and operates as a spacer between the scaphoid (31) and the metacarpus (30).

Provided herein are methods, constructs, and kits for positioning a first bone segment relative to a second bone segment within a subject's body, for example, in order to establish a reduced position of the first and second bone segments. The present disclosure provides, among other things, alternatives to traditional ligament reconstruction and tendon interposition (LRTI) and suture suspension arthroplasty procedures.

A two-piece socket for a ball-and-socket arrangement, including a base and a cap. The socket includes a leg on one of the cap or base of the socket and a receiving groove on the other of the cap or base of the socket, wherein there is at least one opening in the leg which lines up with a corresponding opening in the groove for a fastener to extend through these openings to releasably secure the cap to the base of the socket. The orientation of the fastener is such that the fastener is under shear loading when the cap is pulled apart from the base.

Implantable orthopedic pain management devices are disclosed, including a body with a top surface, a bottom surface, and at least two substantially parallel surfaces, the two substantially parallel surfaces having substantially similar radii of curvature and are substantially trapezoidally shaped, the top surface having a top radius of curvature and the bottom surface having a bottom radius of curvature, the body being configured to be disposed in a joint such that the surfaces are configured to be in intermittent contact with bone surfaces of one or more bones comprising the joint, the body not being coupled to the one or more bones, and a peripheral protrusion disposed substantially at an intersection of at least two surfaces, the peripheral protrusion being formed with the body, substantially spherical, and configured to prevent expulsion of the body from the joint.

A prosthesis for replacing a joint between a first bone and a second bone in a human hand or foot includes first and second rigid blocks (110, 120) interconnected by a flexible bridging structure (130). In certain embodiments, the flexible bridging structure employs a helical spring oriented with its central axis aligned with a central axis of a bone anchor portion of the first rigid block. One or more shear-limiting element (101, 140) is deployed within an internal volume of the helical spring (130) to limit an extent of shear deformation applied to the helical spring. Other aspects of the invention relate to adjustable bone-abutment flanges, an alternative bridging structure employing a helically-twisted leaf spring, and a structure and method for bridging between the first metacarpal and the scaphoid in case of removal of the trapezium from the hand.

A two-piece socket for a ball-and-socket arrangement, including a base and a cap. The socket includes a leg on one of the cap or base of the socket and a receiving groove on the other of the cap or base of the socket, wherein there is at least one opening in the leg which lines up with a corresponding opening in the groove for a fastener to extend through these openings to releasably secure the cap to the base of the socket. The orientation of the fastener is such that the fastener is under shear loading when the cap is pulled apart from the base.

A two-piece socket for a ball-and-socket arrangement, including a base and a cap. The socket includes a leg on one of the cap or base of the socket and a receiving groove on the other of the cap or base of the socket, wherein there is at least one opening in the leg which lines up with a corresponding opening in the groove for a fastener to extend through these openings to releasably secure the cap to the base of the socket. The orientation of the fastener is such that the fastener is under shear loading when the cap is pulled apart from the base.

Techniques for implantable orthopedic pain management devices are disclosed, including incising an opening in a synovial capsule substantially surrounding a joint, using a first tool to form an enlarged opening in the synovial capsule, determining whether to modify the joint, the joint being modified using a second tool if a bone structure coupled to one or more bones is found within the joint and the bone structure is configured to limit articulation of the one or more bones when an implantable device is inserted into the synovial capsule and the joint, and inserting the implantable device into the synovial capsule through the enlarged opening, the implantable device being inserted into the joint using a third tool.

A hemi-arthroplasty bone joint implant has a first part (120) with a stem (111) tor intramedullary implanting into a metacarpal, and a second part (110) to engage the trapezium is a translational manner, a hemi-arthroplasty articulating coupling (121). This allows multi-axial motion with translational movement of the second part over the trapezium and rotation of the first part (110) about the articulating coupling (121, 103). There is also a converter to convert the implant to a toral arthroplasty implant in situ during revision surgery. The second part (110) and the hemi-arthroplasty coupling (100, 123, 121) are removable in situ during revision surgery. The first part (120) has an engagement threaded socket (117) for, after removal of the second part and the hemi-arthroplasty coupling, engaging the replacement coupling (200) and allowing mutual articulation of the first (120) and replacement parts (220). This forms a total arthroplasty joint implant.