Patents Assigned to Health & Research Services Inc.
  • Patent number: 4759769
    Abstract: An artificial disc for a human spine. The disc has upper and lower members hinged together at their rear portions and biased apart at their fronts by stiff coil springs. Rear stop surfaces limit the opening movement of the members. Vertically projecting tabs at the front and side of each member are rigidly screwed to the adjacent vertebrae. Tolerances in the hinge allow limited side to side rocking. The disc and screws are made of titanium alloy or cobalt chrome alloy. In a modified version a hinge pin is replaced by cables tying the members together.
    Type: Grant
    Filed: June 22, 1987
    Date of Patent: July 26, 1988
    Assignee: Health & Research Services Inc.
    Inventors: Thomas P. Hedman, John P. Kostuik, Geoffrey R. Fernie, Brian E. Maki