An implant (10) for use in fixing one segment of a spinal column to another segment thereof by means of at least one rod member, comprises a screw member (11) for insertion in the pedicle of a segment of a spinal column and having an enlarged diameter head (13) with an open ended transverse slot (16)...http://www.google.es/patents/US5217497?utm_source=gb-gplus-sharePatente US5217497 - Apparatus for use in the treatment of spinal disorders
Apparatus for use in the treatment of spinal disorders
