The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 17, 2004
Filed:
May. 10, 2002
Felix Liebrecht, München, DE;
Werner Kraus, München, DE;
Heribert Stephan, München, DE;
Abstract
Bone screw ( ) having a hollow, tubular shaft ( ) consisting of metal, such as titanium, the shaft having a head ( ) at one end and a self-tapping external thread ( ) at the other end. The head ( ) has a hexagonal recess ( ) for inserting a turning tool. An electrically insulated metallic end-piece ( ) which tapers in the direction of the end in the form of a cone or pointed arch, is inserted the other end of the shaft ( ). A receiving coil ( ) is located in the hollow shaft ( ), the terminals ( ) of the coil being electrically coupled to the shaft ( ) and to the end-piece ( ). The space between the end-piece ( ) and the end of the shaft ( ) as well as the interior of the shaft ( ) are filled with a biocompatible insulating compound ( ), such as an epoxy resin. A low-frequency electric voltage can be induced in the receiving coil by an external primary coil which is coupled to an oscillation generator. The electric voltage generates a growth-promoting current in the surrounding tissue, the shaft and the end-piece acting as tissue electrodes (stimulation method according to Kraus and Lechner).