Abstract: Novel reagent compositions and an assay method for the measurement of total and direct bilirubin are disclosed. The reagent compositions comprise an aqueous solution of at least one betaine selected from the group of alkyl betaine, betaine and betaine hydrate, a sulfanilamide diazonium salt, iodide ions and sulfamic acid. In the measurement of total bilirubin, alkyl betaine serves as an accelerator/solubilizer for the reaction of unconjugated bilirubin, and the alkyl betaine, betaine or betaine hydrate, together with iodide ions, minimizes or substantially eliminates interference from hemoglobin and lipemia.

Abstract: A knee prosthesis is provided including a tibial component having first and second generally concave bearing surfaces and a stabilizing post extending upwardly between the first and second bearing surfaces. The knee prosthesis also includes a femoral component having first and second spaced apart, convexly curved condyle bearing surfaces and a cam surface extending between the first and second bearing surfaces. The femoral component is articulatable with the tibial component between an extended position and a flexed position. The first and second femoral bearing surfaces engage the first and second tibial bearing surfaces, respectively, at first and second contact points. Between the extended position and about a 25.degree. flexion angle, the cam surface is spaced apart from a posterior side wall of the stabilizing post to permit movement of the femoral and tibial component as natural physiology dictates. As the knee prosthesis is flexed at about a 25.degree.

Abstract: A reflection plate for a biochemical measuring instrument which is adapted to evaluate a biochemical value by obtaining a reflective property of a reflection surface of the reference reflection plate, obtaining a reflective property of test paper impregnated with biochemical sample and mounted on a test stick, and comparing the two reflective properties, wherein: the reflection surface of the reference reflection plate is depressed from the periphery thereof. Thereby, even though the test stick is required to be placed adjacent to the reflection surface to achieve a uniformity the optical arrangement in obtaining the two reflective properties, the contamination of the reflection surface from the sample can be prevented. Preferably, the reference reflection plate itself may be provided with a depression to defined the reflection surface at the bottom of this depression.

Abstract: The invention relates to a prosthetic implant assembly comprising a base component secured to a bone and a generally planar surface having a recessed portion formed therein. A spring is situated in the recessed portion of the base component and includes a tab extending away from the spring. A bearing component slidably engages the base component to couple the bearing component to the base component and the bearing is provided with an opening for receiving the tab of the spring means therein to lock the bearing component in a fixed position relative to the base component.

Abstract: The invention relates to a heterogeneous immunoassay which is carried out using a multizoned test device. In particular, the invention involves the use of an inhibitor of a label which is used in the assay. The label which may be an enzyme, is attached to a receptor such as an antibody. The inhibitor is not acted upon by the label, but must be removed in order for a signal to be produced. Also described are test strips which can be used for the assay.

Abstract: A bone screw is disclosed for joining bone fragments or for mounting a prosthetic component onto an underlying bone. The bone screw includes a head and an elongated cylindrical shank which is integral with and extends from the head. The shank includes a threaded member and a shoulder member connecting the threaded member and the head, the shoulder member having an outer surface with a porous medium thereon for encouraging bone ingrowth fixation. The outer diameter of the shoulder member is greater than the diameter of a bore of the bone into which the screw is to be threadedly engaged. The head of the screw is provided with a coupling member engageable by a tool for selectively rotating the shank to advance the screw into the bone. As the bone screw is advanced toward a fully seated position, the shoulder member with the porous medium thereon engages the bone in a fitting manner which may be described as a "scratch fit".

Abstract: A modular hip prosthesis for the replacement of a portion of the femur is provided. The prosthesis is assembled from a kit that includes a stem member having an upper portion and a lower portion, with the lower portion sized to be received in the femur. The kit also includes a body member that is sized to replace a portion of the femur and is configured to be received over the upper portion of a stem member. The kit also includes a head member that is sized to replace the head of the femur. A neck member is provided to attach the head member to the body member to form an assembled prosthesis.

Abstract: The invention involves an apparatus useful in analysis of liquid samples. At least 3 zones are provided which contain reactants which interact with the analyte and each other, leading to the detection reaction. The apparatus also has a fluid application means for reception of a liquid, and a waste zone, which absorbs excess liquid after the detection reaction has taken place. The fluid application means and waste zone are positioned at opposite ends of the apparatus.

Abstract: A tool for separating the two components of a modular joint prosthesis intended for implantation in a body. The prothesis includes a component adapted to be fixed to a long bone having an intramedullary canal and further includes an elongated male stem having a uniformly tapered outer surface. In order to accommodate the particular size of long bone to which the component is to be fixed, a properly sized female stem is attached to the male stem before the component is fixed to the long bone. The female stem is adapted to be received in the intramedullary canal for fixation thereto, and has a uniformly tapered inner surface, the angle of the taper being substantially similar to the angle of taper of the outer surface of the male stem. As a result, the male stem and female stem become locked together when the inner surface of the female stem engages the outer surface of the male stem.

Abstract: An apparatus is provided in combination with an instrument for determining the concentration of a medically significant component of a biologically fluid. The apparatus includes an integrated circuit carrier and a socket for removably longitudinally receiving the integrated circuit carrier. The socket includes a first set of electrical contacts and the integrated circuit carrier includes a second set of electrical contacts positioned and arranged so as to be electrically contacted by respective contacts of the first set of electrical contacts. One of the integrated circuit carrier and socket includes upstanding first wall portions extending generally along the longitudinal length of one of the integrated circuit carrier and socket and lying generally between adjacent electrical contacts of the first set.

Abstract: A prosthetic acetabular cup assembly includes a single piece bearing component having an inner bearing surface for receiving a ball attached to a femoral prosthesis and an outer surface. The assembly also includes a shell component for attachment to an acetabulum to replace a natural hip socket includes an inner surface defining a cavity for receiving the bearing component therein. The inner surface of the shell component is formed to include an arcuate groove therein. A formed wire is situated in the arcuate groove of the shell component. The wire is configured so that a portion of the wire extends radially inwardly from the arcuate groove of the shell component to engage an arcuate groove formed in the bearing component to retain the bearing component inside the shell component.

Abstract: A method and apparatus for modifying the distal end of the humerus deformed by injury or disease in preparation for fixation of an elbow joint replacement. A through hole is first formed in the superior aspect of the olecranon fossa communicating with the humeral canal. A stem member which extends from the platform of a distal cut guide tool is received through the hole and extends into the humeral canal. The distal cut guide tool is held so that the platform is generally coplanar with the junction of the medial epicondyle and the trochlea with proper inclinations, both in an anterior view and in a lateral view. Thereupon, a first resected surface is formed by sawing, using as a guide, a planar guiding surface provided on the platform.

Abstract: A prosthetic glenoid component is provided for attachment to a glenoid surface of a scapula to replace a natural socket of a shoulder. The glenoid component includes a molded plastic body having an outer concave bearing surface for engagement by a corresponding humeral head and an inner convex surface for abutting the glenoid surface. A plurality of attachment pegs are integrally molded on the inner surface of the glenoid component for penetrating the glenoid surface to secure the plastic body to the glenoid surface.

Abstract: The present invention relates to instruments for preparing a glenoid surface of a scapula to receive a prosthetic glenoid component to replace the natural socket of a shoulder. More particularly, the present invention relates to a drill guide assembly for aligning and guiding a drill bit to form holes in the glenoid surface at predetermined locations to secure the glenoid component to the glenoid surface. A reamer assembly including a ratchet drive mechanism is also included to facilitate preparation of the glenoid surface prior to installation of the glenoid component.

Abstract: The invention relates to a non-serum based control reagent for glucose determination. Rather than using modified serum, the control reagent contains water, glucose, and the viscosity agent polystyrene sulphonate. The control reagent may also contain a buffer, preservatives, surfactants or surface active agents. A method of making the control reagent is also disclosed.

Abstract: A method of joining a polymeric part and a metallic or ceramic part. The result is a bearing for an orthopedic prosthesis comprising a rigid backing component presenting a mating surface having interstices, a polymeric bearing component having a corresponding mating surface, the bearing component and backing components being joined together by heating the backing component to a temperature sufficient to reduce the viscosity of the bearing component at its mating surface and by forcing the components together with sufficient pressure to cause the bearing component mating surface to flow into the interstices of the backing component mating surface.

Abstract: A modular prosthetic system for mounting a variety of styles of wedges to a tibial tray in order to correct for bone deficiencies, alternatively, in the anterior/posterior direction and in the medial/lateral direction. The wedge is mounted on the tibial tray before the system is implanted. The tibial tray has a pair of spaced transverse smooth bores and coaxial counterbores and the wedge has a pair of spaced transverse threaded bores which are aligned, respectively, with the smooth bores and counterbores when the wedge is mounted on the tibial tray. Cannulated screws having a head, threaded shank, and longitudinal bore are attached so as to extend through an associated bore and counterbore, then are threadedly engaged with the wedge. A bone screw is then received through the bore of the cannulated screw for implanting the system on the proximal end of the tibia. Mating spherical surfaces, respectively, on the cannulated screw and on the bone screw enable the bone screw to attain an optimal orientation.

Abstract: A personal exhaust system for individual use by the members of a surgical team in an operating room. It may be employed in conjunction with a disposable hood or combination hood and gown worn by each such person. Each system includes a d.c. powdered motor and blower unit adapted to be connected, via a light weight power cord to an a.c.-to-d.c. converter and transformer, or switching mode power supply. A filter is utilized to remove contaminants from the air before it exhausts to the atmosphere. Each unit is provided with its own on-off switch and the flow of air for each unit is individually controlled. A battery back-up allows for short excursions away from the power supply. In another embodiment, fresh filtered air may be directed into the hood simultaneously with removal of stale air from the hood and its subsequent filtered exhaustion to the atmosphere.