Abstract: A radial head assembly is provided that includes a stem, a collar, a locking ring, and an articular member. The stem has a convex articular head on one end thereof. The locking ring has a ring wall, which has a ring opening. The ring wall has an angular outer surface and a slot configured to permit the ring wall to radially expand. The angular outer surface engages an angular portion of an interior surface of the collar. The articular member and the locking ring define an articular space within the collar. The articular space is configured to receive the convex articular head.

Abstract: This invention corresponds to a prosthesis for total or hip resurfacing replacement, which comprises a prosthetic femoral head made of highly cross-linked polyethylene, with a diameter ranging from 38 mm to 64 mm, to articulate with a cup or acetabular component made of metal. When the invention applies to total hip replacement, the polyethylene head includes a metal core, which contains inside the female counterpart (14) to mate with the male counterpart (13) of a Morse taper, located at the upper end of the femoral component. The use of this type of head for total hip replacement, articulated with an ultra-polished acetabular cup, reduces the risk of dislocation, transmits less angular and torque forces to the Morse taper than large metal heads, and avoids the problems related to the metal-metal bearing or with the use of large metal heads with thin polyethylene.

Abstract: The artificial joint of the present invention is provided with a cup having a first housing part that opens on one first-direction side, an insert that is housed in the first housing part and has a second housing part that opens on one first-direction side, a movable member having a spherical head part rotatably housed in the second housing part and a neck part extending from the head part, and a connecting part that connects the insert to the cup pivotably around a pivotal axis extending in a second direction; the neck part contacting an edge part of the insert by pivoting around the pivotal axis; the insert pivoting around the pivotal axis; and part of the opposite side of the side pushed in by the neck part across the pivotal axis protruding from the cup to one first-direction side.

Abstract: A trackball that is used notably for pointing at objects on a screen of a computer system comprises a body that is intended to be fixed to a workstation, a sphere that is rotatable with respect to the body, a set of sensors that provide information relating to the relative position of the sphere with respect to the body, and braking means for braking the rotational movements of the sphere with respect to the body. The braking means comprise a friction ring that encircles the sphere. The ring extends mainly in a plane perpendicular to an axis of symmetry of the sphere. The ring is free to move translationally in the plane in which the ring extends.

Abstract: The present invention provides monopolar acetabular liners (32, 54) that can enclose a femoral head (14) to form a hip replacement prosthesis (30, 50), wherein the liner (32, 54) has a rim (34) that creates an orifice, wherein the orifice has a diameter that is smaller than the diameter of the femoral head (14), and wherein the liner (32, 54) encompasses greater than 50 percent of the volume of the head (14), wherein a constraining ring (56) can be used in conjunction with the monopolar constrained acetabular liner (32, 54) to provide additional support for the femoral head (14) to stay with the acetabular liner (32, 54) and avoid dislocation. Assemblies and complete prosthetic replacements are also provided. Liners (32, 54) and constraining rings (56) having no, one or more recesses (36) also are provided.

Abstract: The articulating joint prostheses of the invention demonstrate reduced wear and can include a cup (101) formed of UHMWPE. An insert (150) of a hard material, such as metal, ceramic or cross-linked UHMWPE is positioned within the cup at a location of the contact between the cup and head (102). The shape of either component of the kinematic pair may be modified so as to result in an annular surface contact between the two components, with the insert positioned at the annular surface contact. Fluid trapped between the two components within the inner contour of the annular contact area is pressurized under load due to elastic deformation of the components and exuded out through an inter-articular gap over the surface of contact of the insert. This aids lubrication and reduces wear.

Abstract: Bipolar prostheses which include various structures and other techniques for optimizing material wear and mechanical strength properties. Such prostheses feature, for example, improved resistance to polyethylene wear while also reducing potential for dislocation of the femoral stem from the prosthesis. Such techniques and structures include varying wear resistance and mechanical strength treatment in various components of the prostheses or portions of those components as desired to improve, accentuate or optimize wear performance and dislocation reduction, locking ring structural features, structures for retaining locking rings in the bipolar prosthesis shell, and structures for limiting or reducing movement or rotation of locking rings and liners in bipolar prosthesis shells.

Abstract: An artificial hip cup design having an external groove for accepting a split ring or segmented split rings with knife shaped edges and specially designed set screws which expand the split ring's outer diameter. After the cup is placed in the socket of the pelvic bone, it can be readjusted, if necessary, and then locked in final position.

Abstract: A method of reinforcing the bone in an acetabulum for receiving a prosthetic acetabular implant includes preparing a surface of the acetabulum to receive an acetabular implant. At least one porous generally cylindrical bone reinforcement element is provided. At least one bore is drilled in an area of the acetabulum receiving the prosthetic acetabular implant for receiving at least one and preferably more reinforcement elements in the form of cylindrical pilings. The cylindrical porous bone reinforcement element is inserted in the bore such that an exposed surface of the porous bone reinforcement element is adjacent the surface of the acetabulum. The acetabular implant is then implanted with an outer surface of the acetabular implant supported by the reinforcement members.

Abstract: Bipolar prostheses which include various structures and other techniques for optimizing material wear and mechanical strength properties. Such prostheses feature, for example, improved resistance to polyethylene wear while also reducing potential for dislocation of the femoral stem from the prosthesis. Such techniques and structures include varying wear resistance and mechanical strength treatment in various components of the prostheses or portions of those components as desired to improve, accentuate or optimize wear performance and dislocation reduction, locking ring structural features, structures for retaining locking rings in the bipolar prosthesis shell, and structures for limiting or reducing movement or rotation of locking rings and liners in bipolar prosthesis shells.

Abstract: A method for removing a bearing that is coupled to a prosthetic implant by a ring includes advancing a distal end of a removal tool in a first direction and into a slit formed in the ring. The ring can be caused to expand radially from engagement with the bearing. The distal end of the removal tool can be advanced in a second direction such that the removal tool engages the bearing. The distal end of the removal tool can be further advanced in the second direction such that the removal tool urges the bearing away from the prosthetic implant.

Abstract: A prosthetic joint assembly that includes a shell including an inner surface. The assembly also includes a bearing member including an outer surface. The bearing member is received by the shell such that the outer surface of the bearing member is adjacent the inner surface of the shell. Furthermore, the joint assembly includes a compressible member that is rigidly fixed to the inner surface of the shell or the outer surface of the bearing member to only cover a portion thereof. The compressible member is made of a material that is different from the shell or the bearing member.

Abstract: An acetabular implant for hip replacement surgery includes a shell component and first and second alternative bearing components interchangeably engageable with the shell component to provide a choice in bearing materials. The shell component has an engagement mechanism suitable for locking engagement with the first alternative shell component. A conversion ring is lockingly engageable with the shell component to adapt the shell component to provide an engagement mechanism suitable for locking engagement with the second alternative shell component.

Abstract: A system for replacing a portion of a shoulder joint can include a tray having an outer surface and an inner surface. The outer surface can be adapted to engage a humeral stem. A bearing can include an outer bearing surface and an inner articulating surface. The outer bearing surface can be positioned adjacent to the tray. A ring can be selectively disposed between the tray and the bearing. The ring can define an annular body having a slit formed therein. The ring can be movable between a locked position wherein the ring retains the bearing relative to the tray and an unlocked position. A removal tool can define a proximal end and a distal end. The distal end can define a ring engaging surface and a bearing engaging surface. The ring engaging surface can be adapted to engage the ring at the slit such that the ring expands radially from the locked position away from engagement with the bearing to the unlocked position.

Abstract: A prosthetic constraining device for use with a hip replacement prosthesis that includes an acetabular cup assembly adapted to be bonded to a patient's pelvis and a femoral stem adapted to be bonded to the patient's femur, where the femoral stem includes a ball component at its proximal end received within the acetabular cup assembly to form a ball joint type coupling, and where the constraining device includes a ring having a central aperture, where the ring is adapted to be mounted to a rim of the acetabular cup assembly so that the femoral stem passes through the central aperture, where the diameter of the central aperture is less than the diameter of the ball component on the proximal end of the femoral stem so that the ring assists in maintaining the ball joint type coupling between the acetabular cup assembly and the femoral stem, and where the ring comprises a biologic material, a biologically reabsorbable material and a combination of biologic, or biologically reabsorbable materials.

Abstract: A system for replacing a portion of a hip joint can include a cup having an outer surface and an inner surface. A bearing can include an outer bearing surface and an inner articulating surface. The outer bearing surface can be positioned adjacent to the cup. A ring can be selectively disposed between the cup and the bearing. The ring can define an annular body having a slit formed therein. A removal tool can define a proximal end and a distal end. The distal end can define a ring engaging surface and a bearing engaging surface. The ring engaging surface can be adapted to engage the ring at the slit such that the ring expands radially from a locked position away from engagement with the bearing to an unlocked position. The bearing engaging surface can be adapted to engage the bearing and urge the bearing away from the cup.

Abstract: Methods, systems and devices for preventing prosthetic articulating surfaces from separating from each other. A containment system according to one embodiment seeks to prevent an implant stem head from dislocating from a prosthetic component while providing an increased range of motion over conventional contrained components. In one embodiment, an implant structural member includes a cavity and an opening having a lip, including a web along a portion of the lip. An implant stem head has a cooperating surface that corresponds with the web, so that when the cooperating surface of the implant stem head is aligned with the web, the head may be inserted into the implant structural member. The implant stem head is then rotated and the femoral stem component attached, thereby preventing dislocation of the head.

Abstract: An acetabular prosthesis generally consists of an acetabular component and an acetabular shell. The acetabular component includes an acetabular articulating component and an acetabular constraining component. The articulating component has a hemispherical or dome shape that defines a hemispherical cavity for receiving a femoral ball of a femoral hip stem. The constraining component has a ring-shape body with extensions for locking the femoral ball in the cavity of the articulating component.

Abstract: Bipolar prostheses which include various structures and other techniques for optimizing material wear and mechanical strength properties. Such prostheses feature, for example, improved resistance to polyethylene wear while also reducing potential for dislocation of the femoral stem from the prosthesis. Such techniques and structures include varying wear resistance and mechanical strength treatment in various components of the prostheses or portions of those components as desired to improve, accentuate or optimize wear performance and dislocation reduction, locking ring structural features, structures for retaining locking rings in the bipolar prosthesis shell, and structures for limiting or reducing movement or rotation of locking rings and liners in bipolar prosthesis shells.

Abstract: A prosthetic constraining device for use with a hip replacement prosthesis that includes an acetabular cup assembly adapted to be bonded to a patient's pelvis and a femoral stem adapted to be bonded to the patient's femur, where the femoral stem includes a ball component at its proximal end received within the acetabular cup assembly to form a ball joint type coupling, and where the constraining device includes a ring having a central aperture, where the ring is adapted to be mounted to a rim of the acetabular cup assembly so that the femoral stem passes through the central aperture, where the diameter of the central aperture is less than the diameter of the ball component on the proximal end of the femoral stem so that the ring assists in maintaining the ball joint type coupling between the acetabular cup assembly and the femoral stem, and where the ring comprises a biologic material, a biologically reabsorbable material and a combination of biologic, or biologically reabsorbable materials.

Abstract: Methods, systems and devices related to prosthetic implants, including a device for preventing prosthetic components from separating from each other, and more specifically to an assembly for adapting a prosthetic component to receive a device for preventing an implant stem head from dislocating from a prosthetic component. Methods, systems and devices according to this invention seek to provide improved orthopedic prosthetic components and more specifically, improved constrained components that may be utilized with existing implanted prosthetic components. Liner assemblies and systems according to various embodiments of this invention may include an adapter component designed to link current prosthetic cup geometry to a constrained liner, while providing optimal range of motion and sufficient lever out.

Abstract: Methods, systems and devices related to prosthetic implants, including a device for preventing prosthetic components from separating from each other, and more specifically to an assembly for adapting a prosthetic component to receive a device for preventing an implant stem head from dislocating from a prosthetic component. Methods, systems and devices according to this invention seek to provide improved orthopedic prosthetic components and more specifically, improved constrained components that may be utilized with existing implanted prosthetic components. Liner assemblies and systems according to various embodiments of this invention may include an adapter component designed to link current prosthetic cup geometry to a constrained liner, while providing optimal range of motion and sufficient lever out.

Abstract: A prosthesis for replacement of a ball and socket joint in the human body. The prosthetic components comprise a plurality of separate parts which may be inserted through a hole in the femur of the patient and assembled and attached to the prepared acetabulum of the hip bone to form a cup-shaped first shell. A cup is also passed through the hole in the femur and attached to the first shell to form the socket portion of the joint. A shaft having a first end with a ball formed thereon is inserted in the hole through the femur so that the ball engages the cup for movement therein.

Abstract: The present invention provides monopolar acetabular liners that can enclose a femoral head to form a hip replacement prosthesis, wherein the liner has a rim that creates an orifice, wherein the orifice has a diameter that is smaller than the diameter of the femoral head, and wherein the liner encompasses greater than 50 percent of the volume of the head, wherein a constraining ring can be used in conjunction with the monopolar constrained acetabular liner to provide additional support for the femoral head to stay with the acetabular liner and avoid dislocation. Assemblies, complete prosthetic replacements, and methods of replacing also are provided. Liners and constraining rings having no, one or more recesses also are provided.