Abstract: A modular acetabular anti-protrusio cage and acetabular cup combination includes an acetabular cup having a bone ingrowth-promoting surface and a shaped anti-protrusio cage having one or more fixation flanges. The acetabular cup is attached to acetabular bone, and the anti-protrusio cage is thereafter mounted to the inner surface of the acetabular cup. Alternatively, the anti-protrusio cage can be mounted to the inner surface of the acetabular cup before the acetabular cup is attached to acetabular bone. The flanges of the anti-protrusio cage are joined to the ilium, ischium and/or pubis to secure the acetabular cup and the anti-protrusio cage to the hip bone and to distribute forces away from the medial wall of the acetabulum. After the cup and the cage are mounted in the patient, a bearing insert is secured within the interior of the anti-protrusio cage, and a prosthetic femoral head is positioned in the bearing insert.

Abstract: A method and apparatus for performing minimally invasive hip surgery for implanting a prosthetic acetabular component into a natural acetabulum. The method and apparatus include a driving instrument and driving guide for aligning and driving bone screws and screw-hole plugs. The instrument includes a working section and a driving section connected together with a joint connector. The joint connector enables the working and driving sections to move to various angles relative to each other.

Abstract: A prosthetic component is configured to have intentional interruptions in an articulating face thereof. The intentional interruptions are configured to yield an optimum contact area or bearing surface, particularly with regard to low wear and greater lubricity through the application of lubrication and contact mechanics theory for the particular prosthetic component. Such optimization is applied to a wide range of prosthetic component sizes of the particular prosthetic component. The optimum range of percentage area of relief or interruptions, defined as a percentage of a baseline uninterrupted bearing surface area to be removed by the features of the interrupted bearing surface configuration is from 0.3% to 73.7% for hard-on-hard bearing components and from 5.7% to 83.2% for polyethylene-on-hard bearing components. The range for both hard-on-hard and polyethylene-on-hard implants translates to a relieved area ranging from 0.3% to 31.

Abstract: A medical implant made of polymeric material having an increased oxidation resistance is formed by a method including the steps of placing a resin powder in a sealed container. A substantial portion of the oxygen is removed from the sealed contained by either a vacuum, an oxygen absorbent or by flushing with inert gas. The container is then repressurized with a gas such as nitrogen, argon, helium or neon so that long term storage may be possible. On use, the resin in transferred to a forming device which both melts and forms the resin in an oxygen reduced atmosphere to produce a polymeric raw material such as a rod or bar stock. The medical implant is then formed from this raw material annealed and sealed in an airtight package in an oxygen reduced atmosphere. The implant is then radiation sterilized and thereafter annealed in the package for a predetermined time and temperature sufficient to form cross-links between any free radicals in neighboring polymeric chains.

Abstract: A polymeric implantable orthopaedic device that includes a first layer and a second layer where the first layer has a porosity that is different from the second layer is described. An associated method of producing a polymeric implantable orthopaedic device that includes a first layer and a second layer where the first layer has a porosity that is different from the second layer is also described.

Abstract: The present invention discloses methods for enhancing the wear-resistance of polymers, the resulting polymers, and in vivo implants made from such polymers. One aspect of this invention presents a method whereby a polymer is irradiated, preferably with gamma radiation, then thermally treated, such as by remelting of annealing. The resulting polymeric composition preferably has its most oxidized surface layer removed. Another aspect of the invention presents a general method for optimizing the wear resistance and desirable physical and/or chemical properties of a polymer by crosslinking and thermally treating it. The resulting polymeric compositions is wear-resistant and may be fabricated into an in vivo implant.

Abstract: A prosthetic implant includes first, second and third components. The first component is configured to be disposed within the acetabulum. The second component is in a load bearing relationship with the first component, and is operable to rotate in a first axis of rotation. The second component is inhibited from movement in a second axis of rotation. The third component is in a load bearing relationship with the second component. The third component is operable to rotate in the second axis of rotation, but is inhibited from movement with the first axis of rotation.

Abstract: A medical prosthesis for use within a body which is formed of radiation treated ultra high molecular weight polyethylene having substantially no detectable free radial. Preferred prosthesis exhibits reduced production of particles from the prosthesis during wear of the prosthesis, and are substantially oxidation resistant. Methods of manufacturing wear resistant medical prosthesis and materials used therein are also provided.

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: A prefabricated joint is employed for the prosthetic joint. The joint includes prefabricated socket, ball, and capsule. The capsule is attached from the ball to the socket. The capsule seals the area between the ball and socket and prevents wear debris from entering the body cavity. In the case of the hip joint, the doctor need only attach the prefabricated unit to the femoral unit to connect the prosthetic joint after the prefabricated unit and femoral unit have been placed into the acetabular and femur, respectively.

Abstract: The present invention is intended to provide a cementless prosthetic bearing element which has been molded and which is possible to place in an acetabular socket without cement, the outer surface of the backing being provided with elements to assist stabilization and the ingrowth of bone. Thus, the bearing element is cheaper and easier to produce and provides superior location and installation in the bone. According to the present invention a cementless prosthetic bearing element comprises a backing which supports a bearing liner having a bearing surface, the backing being molded from a rigid polymeric material and said bearing liner being made from elastomeric polyurethane material to which the backing is molded with an outer surface which includes a number of raised engagement features provided in directions extending away from and/or towards the outer periphery of the outer surface.

Abstract: A device for use in surgical procedures involving arthroplasty. The device includes a socket member having a first surface and a second bone engaging surface. The first surface has a bearing surface adapted to receive a counter-component of a joint such as the head of a femur (or prosthesis thereof). The bone engaging surface includes a first, preferably frusto-conical, portion and a second portion preferably including a spherical section.

Abstract: The present invention essentially relates to a hip joint socket system for a “press-fit” anchorage in the bony acetabulum that allows the inserts that articulate with the artificial head to be connected securely, and, using said inserts, also allows the center of the rotation of the socket to be reconstructed, the risk of luxation to be eliminated, and the plane of load application to be varied across an infinite range of positions within a defined angular range.

Abstract: A prosthetic component is configured to have intentional interruptions in an articulating face thereof. The intentional interruptions are configured to yield an optimum contact area or bearing surface, particularly with regard to low wear and greater lubricity through the application of lubrication and contact mechanics theory for the particular prosthetic component. Such optimization is applied to a wide range of prosthetic component sizes of the particular prosthetic component. The optimum range of percentage area of relief or interruptions, defined as a percentage of a baseline uninterrupted bearing surface area to be removed by the features of the interrupted bearing surface configuration is from 0.3% to 73.7% for hard-on-hard bearing components and from 5.7% to 83.2% for polyethylene-on-hard bearing components. The range for both hard-on-hard and polyethylene-on-hard implants translates to a relieved area ranging from 0.3% to 31.

Abstract: A medical prosthesis for use within the body which is formed of radiation treated ultra high molecular weight polyethylene having substantially no detectable free radicals, is described. Preferred prostheses exhibit reduced production of particles from the prosthesis during wear of the prosthesis, and are substantially oxidation resistant. Methods of manufacture of such devices and material used therein are also provided.

Abstract: Femoral head modular resurfacing systems are described. The systems primarily include a head component and a stem component. The configuration of the head component and stem components allow for minimum invasiveness into the femur head region, thus conserving greater amounts of bone tissue than would be possible with conventional hip replacement systems. The systems also provide for various angles and offsets to be achieved between the systems and the femur head. The systems are useful in partial hip replacement procedures, as well as total hip replacement procedures, in which case an optional acetabular component would also be employed.

Abstract: The invention relates to implantable medical devices, particularly, to porous structures for such devices. In one aspect, the invention provides a porous metal scaffold comprising a porous metal network having pores defined by metal webs, the metal webs covered with at least one layer of metal particles bonded to the metal webs. In other aspects, the invention provides methods of forming porous scaffolds. In one such aspect, the method includes providing a polymer foam; forming a skin of biocompatible metal on the polymer foam by low temperature arc vapor deposition; and heating the polymer foam and the metal skin above the decomposition temperature of the polymer foam in an inert gas atmosphere; thereby the polymer foam decomposes producing a green metal foam. In yet other aspects, the invention provides methods of improving stability of porous scaffolds.

Abstract: A prosthetic component is configured to have intentional interruptions in an articulating face thereof. The intentional interruptions are configured to yield an optimum contact area or bearing surface, particularly with regard to low wear and greater lubricity through the application of lubrication and contact mechanics theory for the particular prosthetic component. Such optimization is applied to a wide range of prosthetic component sizes of the particular prosthetic component. The optimum range of percentage area of relief or interruptions, defined as a percentage of a baseline uninterrupted bearing surface area to be removed by the features of the interrupted bearing surface configuration is from 0.3% to 73.7% for hard-on-hard bearing components and from 5.7% to 83.2% for polyethylene-on-hard bearing components. The range for both hard-on-hard and polyethylene-on-hard implants translates to a relieved area ranging from 0.3% to 31.

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: Prosthetic joints, components for prosthetic joints, superhard bearing and articulation surfaces, diamond bearing and articulation surfaces, substrate surface topographical features, materials for making joints, bearing and articulation surfaces, and methods for manufacturing and finishing the same, and related information are disclosed, including a prosthetic hip joint having a polycrystalline diamond compact articulation surface and a counter bearing surface.

Abstract: Prosthetic joints, components for prosthetic joints, superhard bearing and articulation surfaces, diamond bearing and articulation surfaces, substrate surface topographical features, materials for making joints, bearing and articulation surfaces, and methods for manufacturing and finishing the same, and related information are disclosed, including a diamond-surfaced cup for use in a prosthetic joint.

Abstract: The present invention relates to an acetabular cup for receiving a substantially spherical hip joint prosthesis head having an outer surface, the cup including: (a) a ceramic component having a socket surface shaped to rotatably receive the outer surface of the head, and (b) a metal backing in which the ceramic component is received, wherein the ceramic component comprises zirconia-toughened alumina, and wherein the ceramic component is interference fit within the metal backing.

Abstract: An acetabular cup assembly allows pre-operative or interoperative selection and securement of a bearing member within a shell member of the acetabular cup assembly, the bearing member being selected from a plurality of bearing members having different characteristics, including bearing characteristics, securement characteristics, position characteristics and orientation characteristics, so as to enable a surgeon to select those characteristics most appropriate to a particular patient, as determined by a pre-operative assessment or by an evaluation of conditions encountered at an implant site during the implant procedure, and to incorporate the desired characteristics into the acetabular cup assembly with ease and economy.

Abstract: Methods, systems and devices for prosthetic implants having openings that receive insertion members for securing the implants in place. The implants have at least one opening with a tapered section. The insertion members have a head that is spherical, near spherical, toroidal, elliptical, global, or otherwise slightly curved or rounded portion at the outer edge, and are adapted to cooperate with the at least one opening to form a liquid-tight seal.

Abstract: The invention relates to a prosthetic implant comprising a main body portion having a first surface for presentation to a receptive bone surface or into a bone cavity and a second surface for receipt of an articulating joint, and a lug on, and/or a bore in, the main body portion of the implant which is adapted for attachment of a filamentary member, such as a cable. The invention also relates to a surgical tool for gripping the implant, comprising an elongate body having a first end surface for bearing on the prosthetic implant and adapted for attachment of the tool to the implant, directly or indirectly by means of the cable.

Abstract: An acetabulum bone plate includes a central, support portion which is shaped to cover the posterior wall of the acetabulum and a pair of tabs which extend therefrom and attach to the pelvis. Spikes formed on the underside of the central portion engage bone fragments and fix them in place when fragment screws that extend through openings in the central portion are tightened. The fragment screws are angled away from the hip joint.

Abstract: A hip joint prosthesis comprising a femoral stem, adapted for implant into the medullary canal of a human leg femur, said stem having a superior neck portion whose longitudinal axis is arcuate, forming concave and convex portions thereof, and terminating in a globular femoral head, and an acetabular cup, adapted to be attached to a human pelvis. The cup is sized and shaped to rotatingly receive the femoral head. The inferior portion of the cup is relieved by an indentation therein which accommodates the convex contour of the arcuate neck during extension and abduction of the leg. The concave portion of the neck is adapted to arch over and avoid interfering with the superior rim of the cup during hyperflexion of the leg. The indentation in the inferior portion of the cup is intended to receive and accommodate the convex contour of the arcuate neck during extension and abduction of the leg.

Abstract: An endoprosthetic acetabular component of overall cup form is improved by the provision of an outer part (100; 300; 500) for securement to bone and a plurality of inner parts (200; 400; 600) individually selectively interconnectable with the outer part in like manner but providing a dished articulating surface (203; 403; 603) in respectively different predetermined positions varying in depth and/or inclination. The interconnection is preferably rotatably adjustable relative to the cup mouth, suitably by the provision of mutually complementary indented/detented surface formations (104,202; 304,402; 505,607) on the parts. The outer part may also be selectable from a range adapted to respectively different manners of securement to bone.

Abstract: Modular set of an outer shell (1) for an artificial hip joint pan, comprising a shell-shaped outer part (2) and an anchoring aid (7) which is designed as a lug (3, 4), a spike (5) or a hook (6), with the shell-shaped outer part (2) having an end surface (2a) at its equator with bores (2b), and with each anchoring aid (7) having a securing part (3a, 4a, 5a) which is designed to be matched with respect to the end surface (2a) in such a manner that the securing part (3a, 4a, 5a) can be secured at the shell-shaped outer part (2) by means of a screw (6) which engages in the bore (2b).

Abstract: The invention relates to a prosthetic implant comprising a main body portion having a first surface for presentation to a receptive bone surface or into a bone cavity and a second surface for receipt of an articulating joint, and means on the implant adapted for attachment of a filamentary member, such as a cable. The invention also relates to a surgical tool for gripping the implant, comprising an elongate body having a first end surface for bearing on the prosthetic implant and means for attachment of the tool to the implant, directly or indirectly by means of the cable.

Abstract: Metal socket (10) for a joint endoprosthesis, the outer surface (11) of which comprises at least three circumferentially extending surfaces (12, 13, 14) of spherical segments each having a different radius (R1, R2, R3). A metal socket for a joint endoprosthesis has an outer surface which includes at least three circumferentially extending, outwardly convex surface regions each having a different radius. The outwardly convex surface regions are exclusively surfaces of spherical segments, centers of which lie on a common axis of rotation, such that a radius of a medial spherical-segment surface is smaller than a radius of a polar spherical-segment surface, but larger than a radius of an equatorial spherical-segment surface.

Abstract: A hip-joint socket of a hip-joint endoprosthesis is provided, in which the bearing shell of the socket that mounts the ball head of the shaft is made of a ceramic material. The bearing shell (2) of the hip-joint socket (1; 11), in the region of its surface (4) with which it is inserted into the hip bone, is covered with a coating (5; 15) that is made of a biocompatible metal or a biocompatible metal alloy.

Abstract: A composite allograft press comprises a loading frame and a two piece mold to form an composite allograft and in particular an acetabular cup from impacted cancellous bone chips and cement. Pressure is applied by a manually operated lever through a rack-and-pinion gear mechanism to a plunger attached to one part of the mold. Compression load switches in-line with the plunger indicate the correct loading to the mold to produce a composite allograft in which the inner surface is smooth and comprised essentially of hardened bone cement material. The outer portion of the allograft may have limited cement extrusions but the exterior of the cup primarily shows exposed cancellous bone surface. In surgery a composite allograft; e.g., an acetabular cup, is fixed in the acetabulum with bone screws to fill an acetabular defect. A plastic liner is affixed with bone cement directly to the composite allograft cup to receive the femoral component.

Abstract: An acetabular cup is supported by a pelvic bone and includes an outer surface which rests in a cavity, and a bearing surface which receives an articular body of an artificial hip joint and bounded in surrounding relation by a receiving edge. The receiving edge is provided at least at one area with an elevation which partially surrounds the articular head received by the bearing surface. The elevation is provided at a location in which the articular head is least obstructed in its freedom of movement, and has at its apex projecting furthest from the receiving edge a distance from a lowest point of the bearing surface which guides the articular head in substantially surrounding relation.

Abstract: The present invention discloses a method for enhancing the wear-resistance of polymers by crosslinking them, especially before irradiation sterilization. In particular, this invention presents the use of chemically crosslinked ultrahigh molecular weight polyethylene in in vivo implants.

Abstract: The present invention is a backing plate for an acetabular reamer assembly that allows for the attachment of a reamer driver. The acetabular reamer assembly comprises a cutting cup and backing plate, the cutting cup having an external surface with cutting teeth formed therein and having an internal surface, the cutting cup terminating in a peripheral edge. The rigid backing plate has a planar surface which terminates in an outer circumferential edge, the outer circumferential edge being coupled to the peripheral bottom edge of the cutting cup, the rigid plate also having an internal edge profile. The internal edge profile of the rigid backing plate has at least two finger elements protruding from the outer circumferential edge thereof towards a central vertical axis drawn perpendicular to the planar surface of the plate. Further, the finger elements of the backing plate form a holding opening for a reamer driver.