Patents by Inventor Kathryn J. Hoffman

Kathryn J. Hoffman has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5190551
    Abstract: A cement plug received within a bone recess is extracted by forming a bore within the plug, tapping the bore to form internal screw threads therein, engaging the threads with a pulling tool, and applying tension to the tool to extract the plug. The bore is formed through means of a rod inserted into the plug while in a fluid state and/or a drill bit having a tubular guide received therearound to maintain the bit in generally aligned condition with the bone recess and limit the depth to which the bit penetrates the plug. The degree to which the bore is tapped and engaged by the pulling tool is controlled to avoid exceeding the extent of the bore and the screw threads formed therein. One embodiment employs a self-tapping extraction rod which serves both as a tap to form the screw threads and as the pulling tool to apply tension to extract the plug. Another embodiment employs a tap which is separate from the pulling tool.
    Type: Grant
    Filed: December 14, 1990
    Date of Patent: March 2, 1993
    Assignee: Zimmer, Inc.
    Inventors: ALbert K. Chin, Milton B. McColl, Kathryn J. Hoffman, Diane E. Caramore