Knife retraction arm for a curved cutter stapler

A surgical instrument (20) adapted for applying a plurality of surgical fasteners to body tissue, the surgical instrument comprising:a frame having a proximal end and a distal end, with a handle (21) positioned at the proximal end and an end effector (80) positioned at the distal end;the end effector being shaped and dimensioned for supporting a cartridge housing (121) and an anvil (122), the cartridge housing and anvil being relatively movable between a first spaced apart position and a second position in close approximation with one another, and the cartridge housing includes a knife structure adapted for cutting tissue by moving between the cartridge housing and the anvil;a firing mechanism is associated with the end effector and the cartridge housing for selective actuation;the knife structure includes a knife (126) and a knife holder (130), and the knife holder is located on a proximal end of the knife opposite to a cutting edge of the knife, and the firing mechanism includes a knife retraction hook (45), the end of the knife retraction hook including a hook that faces upward to receive the knife holder as the cartridge housing is loaded into the end effector of the linear surgical stapler.