Abstract: The cranial cover can form a contoured surface to conform to a patient's cranium. The cover is an array of generally evenly spaced screw-receiving openings. Arms extend between the screw-receiving openings from one screw-receiving opening to the adjacent screw-receiving openings. The centerline of each arm is angled to the center of the screw-receiving openings between which the arm extends. The four arms of four adjacent screw-receiving openings create a rhombus shaped central opening.

Abstract: The burr hole cover includes a thin plate having radial arms in an exemplary embodiment. Each arm has a distal end opening for receiving a fastener for attaching the plate to the cranium. An enlarged access passageway through the plate, preferably at the plate's center provides a passageway for an intracranial monitoring tube. The passageway is elongated to allow the tube to pass through the burr hole cover at a gentle angle.

Abstract: The metal shell of an acetabular cup has holes that allow a surgeon to screw the shell to pelvic bone. To prevent the debris of ultra-high molecular weight polyethylene ("UHMWPE") or other plastic liner in the shell from migrating through the holes, the present invention seals each screw-receiving hole with a thin UHMWPE disc. The disc snaps into an annular groove in the hole. With the disc in place, debris from the liner does not pass through the screw holes.

Abstract: The tool of the present invention comprises a stem. Cutting teeth extend outward from the stem. The stem has a central, longitudinal passage, connects to a suction or evacuation line. An outlet of the passage is at or near the cutting site. As material is cut, the suction carries the material to the central passage where it is evacuated. In one embodiment, each tooth has a cutting edge and a back side. One or more tubes connect the central passage to the back side of the cutting teeth. Suction from the central passage acts on the tubes to create suction at the cutting site. In another embodiment, the central passage is open at the distal end of the tool. Suction at the distal end cut material toward the distal end of the tool and into the central passage where it is evacuated from the tool.