A cement plug for sealing the medullary canal of a bone to restrict the flow of cement, debris, etc. beyond a predetermined point in the canal. The cement plug, which is executed in a biocompatible plastic, comprises (1) a tubular body that is a slit axially at three or more locations to define resilient fingers, (2) an obturator plate located at the upper end of the body, (3) a tapered conical plug that can be advanced through the lower end of the body and intot he interior thereof, and (4) a threaded bolt that extends through the tubular body and into the conical plug. Locator holes are formed in the obtrator plate, and sharpe edges, teeth, or locator tab(s) are formed on the outer surface of the conical plug so that said plug does not rotate relative to the tubular body of the plug. An insertion tool, including an inner tube and an outer tube, is engaged within the locator by depending plins. The lower end of the inner tube engages the upper end of the threaded bolt. By rotating a handle so that the tubes move relative to one another, a torquing force is imparted to the head of the bolt. The bolt draws the plug upwardly into the interior of the plug body. Such upward movement of the tapered conical plug forces the resilient fingers outwardly into secure engagement with the wall defining the medullary canal. Cement, under pressure, is then forced down the medullary canal. The obturator plate, which is situated perpendicular to the body of the plug at the upper end thereof, serves as a barrier to the flow of cement. The obturator plate extends transversely across the medullary canal and may even bow slightly under such pressure; however, the plug will not slip and the cement will now flow, leak or migrate past the plate and adversely impact upon the resilient fingers. The obturator plate may even serve as a secondary gripping member. The plug thus forms a stable platform atop which a prosthesis may be accurately positioned.
An intersomatic cage to be inserted from the posterior approach between two vertebrae comprises two substantially parallel branches for contact with the vertebral bodies, a linking portion linking the posterior ends of the branches, and a movable spreader member for angularly spreading the two branches after insertion of the cage between the two vertebrae. The cage allows adjustment of the lordosis angle between the two vertebrae during surgery. Ancillary equipment for insertion of the cage includes a rasp for forming a housing for the cage between the two vertebrae, a cage-holder for inserting the cage into the housing, a screwdriver for turning a screw screwed into the spreader member to spread the two branches of the cage, and a guide for successively guiding the rasp, the cage-holder with the cage, and subsequently the screwdriver.
A bone plug for intramedullary insertion into the canal of a bone to restrict the bypass of cement during implant surgery is described. The bone plug is made of a bioabsorbable material and has a tapered central body providing the primary support for the plug. A plurality of radially extending disc-like fins extend from the body at spaced locations. The taper provides the distal fin with a greater degree of flexibility due to the long cantilever, thus permitting an ease of insertion into the intramedullary canal while the larger diameter body and shorter proximal fins lend structural stiffness to resist the migration of the device.
An apparatus comprising an internal bone fixation apparatus for supporting and securing together two sections of a fractured elongated bone within a patient's body. Generally, the apparatus includes first and second fixation portions which are disposed in holes formed in the internal cavity of the fractured bone on respective sides of the fracture, and a means for connecting these fixation portions together. In the preferred version of the present invention, the connecting means is adjustable such that the first and second fixations portions can be drawn together or spread apart in the longitudinal direction, thereby similarly moving the first and second sections of the fractured bone. In addition, the structural and securing portions of the invention are made from strong resilient metals, that are not necessarily compatible for long term contact with the body of the patient. However, the metals are completely isolated from any contact with the body of the patient by insulating materials which are compatible.
A plug system for preventing material from extruding beyond a desired location in a bone tunnel includes a plug member that has an insertion axis extending from a first end and a plurality of interleaving arms disposed about the insertion axis. The arms are affixed at a second end and are flarable at the first end between an insertion position wherein the arms are relatively close packed and a position wherein the arms are flared. A portion of each arm remains in overlapping relation to an adjacent arm. The system further includes an expansion member that has an insertion portion adapted to separate the arms upon progressive entry along the insertion axis from the first end. In use the plug can be inserted either first end first, with the expansion member drawn into the plug by a manipulator, or second end first, with the expansion member driven along the insertion axis.
A cement restrictor is provided for creating a fixed obstruction within a bone. An exemplary cement restrictor includes a member or body that is expandable or transitionable from a first diameter to a second diameter.
