A bone plate is provided for fixation of spaced vertebra. The bone plate has at least one through passage for securing the plate to bone with a bone fixation screw. The threaded shaft of a bone fixation screw is inserted through a bushing located in the through passage of the bone plate and the screw...http://www.google.com.au/patents/US6979334?utm_source=gb-gplus-sharePatent US6979334 - Bone fixation assembly and method of securement
