Abstract: A colorimeter comprises a case, a liquid crystal display (LCD) mounted on the case, a color chart provided on the case to permit holding of a specimen to be compared in close proximity to the color chart, and switches for indicating which color on the color chart the color of the specimen most closely approximates. Each switch is located adjacent a color on the color chart, and the states of the switches drive the LCD to display a reading corresponding to the color on the color chart which most closely approximates the color of the specimen.

Abstract: A tool for removal of a joint prosthesis intended for implantation in a body. The prosthesis 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. The tool serves to disengage is obtained the male stem from the female stem as well as to disengage the female stem from the bone.

Abstract: A modular knee prosthesis assembly for the replacement of a portion of the knee joint is provided. The assembly has a femoral component that is formed to include first bearing surfaces and first means for demountably receiving an optional femoral stem member. The assembly also has a tibial component that is formed to include a platform and second means for demountably receiving an optional tibial stem member. The assembly includes a separate tibial insert that is configured to be supported by the tibial component platform. The tibial insert is formed to include second bearing surfaces that are configured to mate with the first surfaces on the femoral component to permit pivotal movement between the femoral component and the tibial component.

Abstract: A flexible enclosure is applied to a prosthetic joint to isolate wear particles which are produced by interengagement between the components of the joint. The enclosure overlies the joint, and is sealingly affixed to the respective joint components proximate to its ends. The enclosure may be impermeable to fluids and contain a synthetic synovial fluid for lubrication of the joint. Alternatively, the enclosure may be porous having pores of a size ranging between 0.1 and 100 microns across so as to maintain larger wear particles which the body cannot assimilate.

Abstract: A controlled stiffness elongated implant for use in the hip or other appropriate body joint. In the instance of the hip, a ball member fixed to the femur is rotatably engaged with a cup-shaped socket member fixed to the acetabulum of the pelvic bone. The ball member is mounted on one end of a femoral component which has an elongated stem receivable in the intramedullary canal of the femur. The stem has a longitudinal channel therein which lies generally in the coronal plane when the stem is in the implanted condition. The thickness of the stem laterally of the channel is variable between the proximal and distal ends so as to affect the moment of inertia at any given location along the length of said stem to thereby achieve stem flexibility which substantially correlates to the flexibility of the bone.

Abstract: A modular intramedullary nail system for the repair of long bone fractures. The system comprises several base nails of different lengths and diameters, each of which may be anatomically curved, and several extension members of different lengths and diameters. By selection of various combinations of base nails and extension members, nails of substantially any length and diameter can be constructed at the time of surgery. Nails for left and right bones are interchangeable. A unique construction enables an extension member to be readily and fixedly joined to the trailing end of a base nail so as to prevent inadvertent separation of the base nail and extension member while maximizing strength of the modular nail. The base nail is preferably tri-flanged, each flange terminating at a sharp point at its distal end. Cross screws may also be employed to prevent relative motion between the bone and the nail and also serve to prevent unlocking of the extension member from the base nail.

Abstract: A ring-shaped registration device for receiving and holding an activated test strip having a reagent area adapted to receive a blood sample. The registration device is slidably received on the outer peripheral surface of a cylindrical vial on which markings to indicate a range of possible results which might be evidenced by a blood sample. The device includes a central member having a support region for slidably receiving the activated test strip and defining a window for outlining markings on the surface of the vial and on the reagent area of the activated test strip. The reagent area is held in substantially tangential relationship relative to the outer peripheral surface of the vial so as to be selectively positioned intermediate adjacent markings on the surface of the vial. This enables the user to compare an actual blood sample with the range of possible conditions and match the sample with the markings on the vial.

Abstract: A bone vise for holding a bone or bone fragment immobile during surgery to enable a surgeon to perform desired sculpting or other operations thereon. The vise includes a planar base member with an integral threaded post upstanding from its central portion and a platform threadedly received on the post. A plurality of elongated gripper members are pivotally mounted intermediate their ends on the platform about axes which are tangent to a circle whose center lies within a bone receiving and engaging region. Each gripper member has a toothed surface at one end adjacent the bone receiving and engaging region and a cam surface at the opposite end weight biased into engagement with the base member. Rotation of the platform in one direction causes movement thereof away from the base member and enlargement of the bone receiving and holding region for insertion or removal of the bone.

Abstract: An apparatus for forming a blood droplet of a controlled, generally uniform size from a finger which has been pricked to draw blood includes a "funnel" member providing an upper edge across which the finger is drawn to deposit blood on a surface down which the blood flows under the influence of gravity to a lower edge terminating at a point. The blood flows toward the point, forms into the droplet at the point, and, owing to gravity and the surface tension of the blood, forms into the substantially uniformly sized droplet which falls onto a test strip positioned beneath the point.

Abstract: A three-component prosthetic joint comprising a first bone-attachable component having a planar articular surface and a second bone-attachable component having an arcuate articular surface and a substantially congruent bearing component held therebetween, avoids extrusion of the bearing component without reduction in the efficacy of the prosthesis as an implantable joint when the substantially congruent planar articular surfaces of the bearing component and the first component are in free-floating contact and the substantially congruent arcuate articular surfaces of the second component and the bearing component are unicentric and include a system of interlockable flanged grooves which prevent both separation of the arcuate surfaces when interlocked and also medial-lateral movement therebetween.

Abstract: A drill stop apparatus for use with an elongated drill bit is provided. The drill bit has a drilling end that is used to drill a hole of a specified, predetermined depth. The bit also has a plurality of circumferentially extending, axially spaced grooves formed on its outer surface. The drill stop includes a body having a first end and formed to include an axially extending bore that is sized to receive the drill bit to permit the bit to be moved axially within the body. The body also has a cavity that extends substantially perpendicularly through the bore. A plunger is provided that is sized to be received in the cavity for releasably engaging one of the plurality of grooves in the drill bit to lock the drill bit against axial movement within the body member such that a specified length of the drill bit extends beyond the first end of the body member.

Abstract: A submergible, post-type dental implant system for anchoring an artificial crown or bridge in a row of teeth or edentulous or partially edentulous area includes a root structure which is surgically implanted transgingivally and into the bone therebeneath, an implant head which is compatibly sized and shaped to fit over an upper tapered portion of the root structure. Prior to the assembly of these two titanium alloy components, a healing cap is disposed over the tapered portion of the root structure during the time interval for healing which may be as much as three to six months. After the healing periods has ended, a tool is used to remove the healing cap and thereafter the implant head is aligned and slid over the top tapered portion of the root structure.

Abstract: A low oiling gel filled article comprising a polydiorganosiloxane gel contained within a polysiloxane rubber envelope. The gel is characterized as being the addition product of a first prepolymer having silicon-bonded additional radicals on a terminal silicon atom, and a second prepolymer having silicon-bonded addition radicals on several intermediate silicon atoms. The polydiorganosiloxane prepolymers, and complex fluid, as well as processes for making same, are also disclosed herein.

Abstract: An automated chemical testing apparatus which includes a continuous flow front end portion and a discrete flow back end portion. Also provided is a collecting means for separately collecting these sample segments and the intersample segments, means for analyzing these sample segments, and a waste collection means for collecting waste fluids.