A mechanically expandable retractor for use in arthroscopic surgery. The retractor has an expanding portion at its distal end for expanding against sub-surface tissues when the retractor is in use. The expanding portion includes a plurality of radially expanding The radially outermost surface of each...http://www.google.es/patents/US5454365?utm_source=gb-gplus-sharePatente US5454365 - Mechanically expandable arthroscopic retractors
