Patent ID: 7641659

Claim:
A surgical instrument for providing an access opening to spinal column area, the surgical instrument comprising: a) a first wire and a second wire for locating an access opening site; b) an incremental opening arrangement having a plurality of nested members, the plurality of nested members including at least: i) a dissector member slidably positionable over the first and second wires with the first and second wires being received within at least a portion of the dissector member, the first dissector member configured to provide an access opening at the access opening site; ii) a sleeve member slidably positionable over the dissector member, the sleeve member being sized and configured to expand the opening area of the access opening at the access opening site; wherein the sleeve member is a second sleeve member and the plurality of nested members further includes a third sleeve member and a fourth sleeve member, each of the nested members being configured to incrementally expand the opening area of the access opening at the access opening site.