Surgical retractor having low-friction actuating means and contoured blade arms

Abstract

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.

1 . A surgical retractor for retracting generally opposed body tissue edges away from each other so as to form a tissue opening therebetween, said tissue opening extending generally in an opening geometrical plane, each of said tissue edges intercepting a tissue outer surface and a tissue inner surface, said surgical retractor allowing the insertion of a surgical implement into said tissue opening, said surgical retractor comprising: 
 a generally elongated guide member, said guide member defining a guide member first end and a generally opposed guide member second end;    a first spreader arm and a second spreader arm, said first spreader arm defining a first arm first end and a generally opposed first arm second end, said second spreader arm defining a second arm first end and a generally opposed second arm second end; said first and second spreader arms being mechanically coupled to said guide member adjacent said first and second arm first ends so that said first and second arm second ends are unattached to one another and positioned generally away from said guide member; said first and second spreader arms being movable relative to each other along said guide member between a first position wherein said first and second spreader arms are in a generally adjacent relationship relative to each other and a second position wherein said first and second spreader arms are in a generally spaced apart relationship relative to each other;    a first retractor blade and a second retractor blade respectively extending from said first and second spreader arms, said first and second retractor blades respectively defining a first and a second blade contacting surface for respectively engaging said opposed body tissue edges during retraction thereof away from each other;    an actuator, said actuator effecting relative movement of said first and second spreader arms along said guide member;    an interfacing member, said interfacing member being mechanically coupled to either one of said first or second spreader arms and providing a friction-reducing mechanical interface between said actuator and either one of said first or second spreader arm.