Abstract: To facilitate insertion of an implant while retaining a cut in an opened state. There is provided a spreader 1 for high tibial osteotomy to be inserted into a cut made in the deformed femur or tibia of a patient with knee osteoarthritis, and to open the cut so as to make a space that allows insertion of an implant, comprising: two pairs of swinging members 2a/2b and 3a/3b which are respectively connected in a relatively swingable manner by hinge parts 6 and 7 disposed at the distal end; and two opening/closing mechanisms 4 and 5 which open/close these two pairs of swinging members 2a/2b and 3a/3b respectively about the axes of the hinge parts 6 and 7, wherein the two pairs of swinging members 2a/2b and 3a/3b are detachably assembled in the axial directions of the hinge parts 6 and 7.

Abstract: To provide a spinous process spacer that can be stably inserted and fixed between split faces of a split spinous process in a gapless manner, without made-to-order production for each patient. There is provided a spinous process spacer (1) for insertion between split halves of a spinous process resulting from longitudinal splitting of the spinous process, wherein the spinous process spacer is formed in an approximately cylindrical shape and the opposite end faces (2, 3) thereof are constituted by planes which mutually form a fixed angle.

Abstract: Bone connector including a first joint and a second joint insertable and securable into respective cut bone pieces for joining the cut bone pieces. Each joint has a flat end surface flush with the cut end of the corresponding cut bone piece when secured therein. The first joint includes a stepped hole having a coaxial hole portion, a shoulder with a surface substantially perpendicular to the longitudinal direction of the joints, and an innermost engaging portion. The second joint includes a stepped shaft having a first shaft fitting the coaxial hole portion and an engaging portion for engaging the innermost engaging portion of the first joint, which hold the joints coaxially along a line, as well as a plate spring member. The joints both include cylindrical bodies of substantially equal diameter for connecting the cut bone pieces, and at least outer surface portions of the joints are made of a material having a bioactive affinity with the human body or biocompatibility with human tissue.

Abstract: An artificial socket comprising a composite body of a calcium phosphate compound and an in vivo-absorptive polymeric material. The artificial socket is embedded and secured in the pelvis side of the artificial hip joint. The socket has a configuration of a semi-spherical shell body, and the thickness thereof is thinner than that of a conventional artificial socket and the inner diameter thereof is substantially the same as that of a real socket in a human bone. An artificial hip joint using the artificial socket and a fixing screw suitable for the fixation of the socket in the pelvis are also disclosed.

Abstract: A guide apparatus of an intervertebral implant which is adapted to firmly fix an implant between adjacent corpus vertebrae includes a grip portion. A hollow inner tube is connected to the grip portion, in which an implant insertion tool can be removably inserted. A first guide projection is provided at the front end of the inner tube to protrude forward therefrom. A movable outer tube is rotatably fitted onto the inner tube. A second guide projection is provided at the front end of the movable outer tube to protrude forward therefrom.

Abstract: An artificial vertebra spacer is embedded in and bridges a space between two adjacent vertebrae which are positioned superiorly and inferiorly of a removed intervertebral disk, respectively. The artificial vertebra spacer includes a hollow cylindrical member, and a helical screw thread disposed integrally on and extending helically around the hollow cylindrical member. A substantially rectangular flange portion is provided at one end of the hollow cylindrical member. The flange portion is provided with at least one hole through which at least one screw passes to fix the spacer.

Abstract: An anchor including a shank formed from a hardened product of a calcium phosphate compound. The anchor having a strength capable of retaining its original shape, before, during and after insertion into a pre-drilled hole of a bone, and a brittleness capable of causing its original shape to disintegrate as a result of a breakage of the shank upon an application of a driving force from the screw to the shank during a driving of the screw through the anchor inserted in the bone. The present invention also relates to a method for fixing a screw in a bone. Using the anchor of the present invention, it becomes possible to easily and reliably fix a screw in a bone having a reduced strength.

Abstract: An intramedullary nail for a humerus is disclosed which is designed to be inserted in a medullary cavity of a fractured humerus. The nail includes an upper rod portion for location in the upper portion of the humerus and a lower oblique portion for location in the lower portion of the humerus. The upper rod portion is longer than the lower oblique portion, with the lower oblique portion having an oblique axis inclined with respect to the axis of the upper rod portion.

Abstract: An intramedullary nail inserting and mounting instrument includes a base portion which can be mounted to one end of an intramedullary nail inserted in bone marrow of a pair of bone pieces of a fractured bone to be interconnected, a guide shaft portion which is integrally provided on the base portion and which extends in the direction of an extension of the intramedullary nail, a pressing member which is movable along the guide shaft portion to come into contact with one end of one of the bone pieces, and a pressing member moving device which moves the pressing member along the guide shaft portion. The disclosure also addresses a method for inserting and securing the intramedullary nail to the fractured bone using the mounting instrument.

Abstract: A bone connector including a first joint which is inserted and secured in one of cut bone pieces to be interconnected at the cut end thereof, a second joint which is inserted and secured in the other bone piece at the cut end thereof, and engaging portions provided on the first and second joints to connect the same.

Abstract: Two posterior spinal fusion members are secured to a plurality of vertebrae which constitute a spine. The posterior spinal fusion members are fixed to both sides of the spinous processes of the vertebrae. A fixing instrument is attached to each posterior spinal fusion member. The fixing instrument includes a rod-shaped connecting member and two hooks slidably attached to both ends of the connecting member. Elongated holes are formed in the portions of the connecting member where the hooks are attached. Male screws are driven through the elongated holes. The surface around the opening of each elongated hole where the head of the associated male screw slides is formed as the bottom of a recess which is shallow on the associated end side of the fixing instrument and is deep on the connecting member side.

Abstract: An artificial vertebra spacer is embedded in and bridges a space between two adjacent vertebrae which are positioned superiorly and inferiorly of a removed intervertebral disk, respectively. The artificial vertebra spacer includes a hollow cylindrical member, and a helical screw thread disposed integrally on and extending helically around the hollow cylindrical member. An annular plate has a tubular member fitted in an axial end of the artificial vertebra spacer and a circular flange extending radially outwardly from the tubular member. The circular flange is fastened to the helical screw thread by screws when the artificial vertebra spacer is embedded in the vertebrae. Each of the artificial vertebra spacer, the annular plate, and the at least one screw is made of a titanium alloy.

Abstract: A vertebral connecting plate assembly includes a vertebral connecting plate which is provided, on its opposite ends, with vertebra connecting portions to be connected to associated vertebral members or bodies. The vertebra connecting portions have threaded holes, and the set screws of the present invention have engaging screw portion, which are engaged in the associated threaded holes of the vertebral connecting plate. Thrusting screw portions of the set screws, which are thrust in the vertebral members or bodies, have a pitch (P1) larger than the pitch (P2) of the engaging screw portions.

Abstract: An apatite coated article comprising a substrate having thereon an apatite layer which is formed by flame spraying apatite powder at from about 2,000.degree. to 4,000.degree. C., and a process for producing such an apatite coated article.

Abstract: An instrument for observation and/or cultivation of cells which has a ceramic coating having a good biocompatibility on a surface thereof to be contacted with said cells. The cells on the instrument of the present invention can be cultivated under the conditions similar to those in vivo, and also can be observed in an optical microscope. The instrument can be sterilized with any sterilization process well-known in this field of technology.

Abstract: A process for producing calcium phosphate ceramics having a porous surface is described, which comprise the steps of:a) preparing untreated calcium phosphate ceramics, which comprises a mixture of hydroxyapatite and tricalcium phosphate, andb) treating said untreated ceramics with an acidic solution to selectively dissolve the tricalcium phosphate in the surface of the ceramics.

Abstract: Ceramic composite comprising a porous ceramic body having directly fitted thereon a dense ceramic body, the composite is produced by a process which comprises the steps of: separately producing the porous ceramic body and the dense ceramic body, inserting a projecting portion of the dense body into a bore portion of the porous body, and simultaneously sintering both the dense and porous bodies at a sintering temperature. The ceramic composite has excellent properties such as heat resistance, resistance to thermal cycle, water resistance and in vivo compatibility, and therefore is particularly useful as an implant material such as an artificial tooth root, an artificial bone and a percutaneous device.

Abstract: An artificial intervertebral disc comprises a pair of end bodies which are provided, on their outer surfaces, with apatite layers. The disc includes a medical synthetic polymeric intermediate which is held between the end bodies through connecting members.