A surgical instrument adapted for applying a plurality of surgical fasteners to body tissue includes a frame having a proximal end and a distal end, with a handle positioned at the proximal end. The instrument also includes a cartridge housing and an anvil. The cartridge housing and anvil are 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 adapted for cutting tissue by moving between the cartridge housing and the anvil. A firing mechanism is associated with the cartridge housing for selective actuation. The instrument also includes a tissue retention feature having an upper member and a lower member maintaining tissue between the cartridge housing and the anvil during treatment, wherein the upper and lower members respectively include channels associated with the knife for guiding it between the cartridge housing and the anvil.