Abstract: The improved joint prosthesis includes a metal-based substrate forming an articulatory surface for the joint prosthesis, wherein the metal-based substrate is coated with a ceramic or ceramic-based surface coating of a thin film doped silicon nitride (Si3N4) layer thereon, as disclosed in U.S. Pat. No. 6,881,229. The ceramic coating provides improvements in ultra-low wear over an extended service life, with dramatically reduced risk of brittle fracture when articulated or moved against articulation surfaces such as an acetabular cup in a hip prosthesis. In one preferred formation process, the ceramic coating is applied to the metal substrate by vapor deposition to mirror the surface finish of the substrate, and then polished to a smoother surface finish.

Abstract: An improved hlp prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.

Abstract: An improved hip prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.

Abstract: The present invention is directed to a rotating/non-rotating tibia base plate/insert system. In one illustrative embodiment, the device comprises a tibia base plate, an insert adapted to be positioned above the base plate, and at least one removable pin that, when installed, engages at least a portion of the insert and the base plate to thereby prevent relative rotation between the insert and the base plate.

Abstract: A set of distal femoral knee prostheses which are designed to be more narrow in medial/lateral dimensions with increasing anterior/posterior size than existing prostheses to more closely correspond to the physical anatomy of female patients. The prostheses are designed to have a substantially trapezoidal shape or profile when viewed distally which features a more pronounced narrowing of the medial/lateral dimensions beginning at the posterior end of the prostheses and progressing anteriorly to the anterior end of the prostheses. Additionally, the prostheses each include a reduced profile patellar sulcus and reduced profile anterior condyles to more closely conform to the anatomy of a resected femur, and also include sulcus tracking optimized to conform to female anatomy.

Abstract: An improved hip prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.

Abstract: A ceramic-metal composite articulation is provided with substantial elimination of wear debris, wherein a ceramic material is provided with superior mechanical properties tailored for articulating with ceramic articulations having high flexural strength (greater than about 700 MPa), high fracture toughness (greater than about 7 MPam1/2) and a high Weibull modulus (greater than about 20), in comparison with presently available bio-ceramics such as alumina or zirconia. The mechanical property enhancement enables ceramic materials with greater reliability and significantly reduced in-vivo fracture risk to be obtained. Preliminary in-vitro wear performance, to several million cycles using established test protocols, of head/cup components in a prosthetic hip joint made from these ceramics also demonstrates the ultra low wear characteristics.

Abstract: An improved knee prosthesis includes a ceramic tibial component for articulation with natural or prosthetic (re-surfaced) femoral surfaces. The ceramic tibial component is provided in the form of a ceramic monoblock adapted for fixation relative to the patient's tibial bone, or alternately in the form of a ceramic bearing insert component carried by a tibial baseplate member which is adapted in turn for fixation relative to tibial bone. In either form, the ceramic tibial component includes at least one upwardly concave articulation surface for movable bearing engagement by a generally convex or condylar shaped femoral articulation surface. The ceramic tibial component provides improved wear characteristics with extended service life.

Abstract: An improved hip prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.

Abstract: A ceramic-metal composite articulation is provided with substantial elimination of wear debris, wherein a ceramic material is provided with superior mechanical properties tailored for articulating with ceramic articulations having high flexural strength (greater than about 700 MPa), high fracture toughness (greater than about 7 MPa1/2) and a high Weibull modulus (greater than about 20), in comparison with presently available bio-ceramics such as alumina or zirconia. The mechanical property enhancement enables ceramic materials with greater reliability and significantly reduced in-vivo fracture risk to be obtained. Preliminary in-vitro wear performance, to several million cycles using established test protocols, of head/cup components in a prosthetic hip joint made from these ceramics also demonstrates the ultra low wear characteristics.

Abstract: The present invention is directed to a rotating/non-rotating tibia base plate/insert system. In one illustrative embodiment, the device comprises a tibia base plate, an insert adapted to be positioned above the base plate, and at least one removable pin that, when installed, engages at least a portion of the insert and the base plate to thereby prevent relative rotation between the insert and the base plate.

Abstract: A ceramic-metal composite articulation is provided with substantial elimination of wear debris, wherein a ceramic material is provided with superior mechanical properties tailored for articulating with ceramic articulations having high flexural strength (greater than about 700 MPa), high fracture toughness (greater than about 7 MPam1/2) and a high Weibull modulus (greater than about 20), in comparison with presently available bio-ceramics such as alumina or zirconia. The mechanical property enhancement enables ceramic materials with greater reliability and significantly reduced in-vivo fracture risk to be obtained. Preliminary in-vitro wear performance, to several million cycles using established test protocols, of head/cup components in a prosthetic hip joint made from these ceramics also demonstrates the ultra low wear characteristics.

Abstract: An electrosurgical knife is provided with an improved surface coating designed for substantially non-stick hemostatic cutting of soft patient tissue. The electrosurgical knife includes a conductive knife blade adapted for connection to a suitable high frequency current source for electrocauterizing tissue at the point of contact to prevent or minimize bleeding. The knife blade includes the improved surface coating formed on at least a cutting edge thereof, wherein the outer surface of the coating includes a relatively non-stick constituent such as an aromatic hydrocarbon in combination with a relatively hard constituent such as a ceramic. The surface coating is additionally loaded with a substantially uniformly dispersed matrix of conductive material for transmitting the electrical energy to patient tissue primarily by conduction.

Abstract: An electrosurgical knife is provided with an improved surface coating designed for substantially non-stick hemostatic cutting of soft patient tissue. The electrosurgical knife comprises a conductive knife blade adapted for connection to a suitable high frequency current source for electrocauterizing tissue at the point of contact to prevent or minimize bleeding. The knife blade includes the improved surface coating formed on at least a cutting edge thereof, wherein the outer surface of the coating includes a relatively non-stick constituent such as an aromatic hydrocarbon in combination with a relatively hard constituent such as a ceramic. The surface coating is additionally loaded with a substantially uniformly dispersed matrix of conductive material for transmitting the electrical energy to patient tissue primarily by conduction.

Abstract: An electrosurgical knife is provided with an improved surface coating designed for substantially non-stick hemostatic cutting of soft patient tissue. The electrosurgical knife includes a conductive knife blade adapted for connection to a suitable high frequency current source for electrocauterizing tissue at the point of contact to prevent or minimize bleeding. The knife blade includes the improved surface coating formed on at least a cutting edge thereof, wherein the outer surface of the coating includes a relatively non-stick constituent such as an aromatic hydrocarbon in combination with a relatively hard ceramic constituent. The surface coating is additionally loaded with a substantially uniformly dispersed matrix of conductive material for transmitting the electrical energy to patient tissue primarily by conduction.

Abstract: A self-venting cement restrictor or bone plug is provided for insertion into the medullary canal of a patient bone during orthopedic surgery. The cement restrictor includes a valve member which accommodates passage of air and body fluids therethrough as the cement restrictor is placed to avoid pressurizing the downstream medullary space. An installation tool is manipulated in the course of cement restrictor installation for shifting the valve member to a closed position, whereby the cement restrictor retains bone cement introduced subsequently under pressure within the upstream medullary space.

Abstract: An improved tibial prosthesis is provided for a prosthetic knee wherein the tibial prosthesis includes a mobile bearing member designed to better accommodate a natural range of flex knee motion and force loads applied to the knee joint. The improved tibial prosthesis comprises a tibial component defining a support tray for receiving and supporting a bearing member which in turn defines upwardly presented medial and lateral condylar recesses for respective seated engagement with medial and lateral condyles of a femoral prosthesis. A short lock rim of part-circular shape projects upwardly from the periphery of the tibial support tray, at the medial end thereof, to engage and constrain the bearing member for rotation within the lock rim through a short arcuate path of motion relative to a center axis defined by the geometry of the lock rim, thereby permitting a small degree of anterior-posterior movement of the bearing member lateral end relative to the tibial tray.

Abstract: A prosthesis having a proximal portion of a stem formed as a wedge having opposed tapers such that prostheses can be thrust into a medullary canal and achieve fixation without unduly stressing the cortical bone remaining in the femur. Ribs secure the prosthesis against medial-lateral motion. Simultaneously, a degree of flexibility is provided in an anterior-posterior direction. A slotted distal portion of the stem is flared to enhance fixation distally.

Abstract: A prosthesis having a proximal portion of a stem formed as a wedge having opposed tapers such that prostheses can be thrust into a medullary canal and achieve fixation without unduly stressing the cortical bone remaining in the femur. Ribs secure the prosthesis against medial-lateral motion. Simultaneously, a degree of flexibility is provided in an anterior-posterior direction. A slotted distal portion of the stem is flared to enhance fixation distally.

Abstract: An improved knee joint prosthesis is provided of the type having a femoral component for attachment to the lower end of a patient's femur and an interengagable tibial component for attachment to the upper end of the patient's tibia. The tibial and femoral components are each formed from a high strength biocompatible material, with the tibial component typically supporting a meniscal bearing member of a high density plastic or the like for engaging the femoral component to accommodate natural or near-natural knee flexion. The bearing member includes an upwardly projecting stabilizing post having a posterior cam surface for engagement by a removably mounted stabilization rod extending between medial and lateral condyles of the femoral component. When used, the stabilization rod contacts the stabilization post during moderate to severe flexion of the knee prosthesis to extend the range of stable flexion of the prosthesis.