A retractor for performing surgery, for instance cardiac surgery on the coronary organs of a patient, which has a driving member to which the surgeon input is applied in the form of a mechanical force or torque, a thoracic structure engaging member which interfaces and retracts the patient's thoracic structure when surgeon input is applied to the movable driving member, and a surgeon input load-reducing and load-normalizing mechanism provided in at least one mechanical interface between retractor components where relative motion therebetween occurs. The load-reducing and load-normalizing mechanisms are preferably non-lubricated, thereby tending to ensure an inert and sterile environment during surgery. The retractor is comprised of a locking arrangement allowing a retractor spreader arm to be secured at any longitudinal position along the rack bar, independently of the pinion's position. The thoracic retractor according to this invention tends to improve the efficiency and safety of surgery by reducing the surgeon input required to achieve retraction, and by allowing said input to be applied more uniformly and in a controlled manner free from sudden movements through the normalization of retractor variables.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. patent application Ser. No. 09/740,001, filed on Dec. 20, 2000, now U.S. Pat. No. 6,416,470.
U.S. patent application Ser. No. 09/740,001 is a continuation of international PCT/CA99/00593 filed on Jun. 25, 1999 and designating the United States.
Priority Data
Jun 26, 1998 [CA] 2,237,887 Jun 25, 1999 [WO] PCT/CA99/00593
