Abstract: An intramedullary stem (1) is for a CMC joint implant. It has a distal bone-engagement end (10) and a proximal end (11) for engaging an articulation component such as a ball to complete a ball-and-socket coupling to a trapezium-contacting platform. The stem has an integral body (2) of material with an external surface for engaging a bone and with an aperture (3) leading to a socket (4) in the proximal end for engaging an articulation component ball or the like. The stem comprises a proximally extending projecting portion 5) which partly surrounds the socket. It is of PEEK material, which provides the desired strength and bone-contacting properties. The stem may have a coating over an elongate portion (203) of the surface extending distally and also in a ring (204) around the proximal end, to achieve optimum adhesion without excessive difficulty in extraction during revision surgery.

Abstract: A set of tools for installation of a stem implant into a bone comprises a stem-shaped priming tool (1) having a distal tip (32) and a plurality of cutting teeth (31) along a length thereof and a plurality of stem-shaped broaches (2, 3, 4, 5, 6) of different size. Each of the broaches have a distal tip (32) and a plurality of cutting teeth (31) along a length thereof. The priming tool (1) is shorter than, has more cutting teeth (31) per unit length, and has a sharper distal tip (32) than the smallest broach.

Abstract: 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.

Abstract: An articulation component (1, 100) is for a bone joint hemiarthroplasty implant having an intramedullary stem (50) with a socket (53). The articulation component has a proximal saddle (2, 110) for non-engaging abutment with a proximal bone and a ball (4, 104) for engaging in the stem socket (53). The saddle has a distally facing recessed surface (10, 110) for engagement with the stem proximally facing surface (55) to define limits of articulation, in one case a cone of motion of about 60° with minimal risk of socket dislocation. Also, the saddle has an enlarged lateral-most edge portion (11, 111, 211) on two diametrically opposed sides of the neck, for conformity with a patients' anatomy.

Abstract: A hemi-arthroplasty bone joint implant has a first part (120) with a stem (111) tor intramedullary implanting into a metacarpal, mid 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 total 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.

Abstract: A set of tools for installation of a stem implant into a bone comprises a stem-shaped priming tool (1) having a distal tip (32) and a plurality of cutting teeth (31) along a length thereof and a plurality of stem-shaped broaches (2, 3, 4, 5, 6) of different size. Each of the broaches have a distal tip and a plurality of cutting teeth along a length thereof. The priming tool (1) is shorter than, has more cutting teeth (31) per unit length, and has a sharper distal tip (32) than the smallest broach.

Abstract: A hemi-arthroplasty bone joint implant has a first part (120) with a stem (111) tor intramedullary implanting into a metacarpal, mid 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 total 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.

Abstract: A set of tools for installation of a stem implant into a bone comprises a stem-shaped priming tool (1) having a distal tip (32) and a plurality of cutting teeth (31) along a length thereof and a plurality of stem-shaped broaches (2, 3, 4, 5, 6) of different size. Each of the broaches have a distal tip and a plurality of cutting teeth along a length thereof. The priming tool (1) is shorter than, has more cutting teeth (31) per unit length, and has a sharper distal tip (32) than the smallest broach.

Abstract: 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.

Abstract: 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.

Abstract: A set of tools for installation of a stem implant into a bone comprises a stem-shaped priming tool (1) having a distal tip (32) and a plurality of cutting teeth (31) along a length thereof and a plurality of stem-shaped broaches (2, 3, 4, 5, 6) of different size. Each of the broaches have a distal tip (32) and a plurality of cutting teeth (31) along a length thereof. The priming tool (1) is shorter than, has more cutting teeth (31) per unit length, and has a sharper distal tip (32) than the smallest broach.

Abstract: A bone joint implant (1) has a proximal part (120) for translational motion over the trapezium in a first carpometacarpal joint and a distal part (110) for intramedullary engagement in the first metacarpal bone. An articulating coupling (103, 121, 123) is for multi-axial motion with translational movement over a bone in one part (120) and rotation in the other part (110) about the articulating coupling (121, 103). A flange (105) extends radially and around the coupling to limit relative rotational motion of the proximal and distal parts about the coupling, and to provide resilience for contact between the proximal and distal parts. The flange has a contoured surface (101) matching an abutting surface (125) of the proximal part (122) upon articulation of the parts in use to extreme positions.

Abstract: 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.

Abstract: Bone joint implants are described herein. The bone joint implants may comprise a metallic proximal platform configured for translational motion on the trapezium bone; a distal stem configured for intramedullary engagement with an end of the first metacarpal bone; an articulating coupling between the proximal platform and distal stem; and a proximal non-metallic wear surface and a distal non-metallic wear surface.

Abstract: Bone joint implants are described herein. The bone joint implants may comprise a metallic proximal platform configured for translational motion on the trapezium bone; a distal stem configured for intramedullary engagement with an end of the first metacarpal bone; an articulating coupling between the proximal platform and distal stem; and a proximal non-metallic wear surface and a distal non-metallic wear surface.

Abstract: Bone joint implants are described herein. The bone joint implants may comprise a metallic proximal platform configured for translational motion on the trapezium bone; a distal stem configured for intramedullary engagement with an end of the first metacarpal bone; an articulating coupling between the proximal platform and distal stem; and a proximal non-metallic wear surface and a distal non-metallic wear surface.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.