Surgical fastener cartridge with improved body tissue cutting knife assembly

Claim 1

In a surgical fastener cartridge which is adapted for use with an actuator apparatus having a rigid frame and a generally U-shaped protion for receiving the fastener cartridge, the actuator apparatus actuating the fastener cartridge to apply substantially parallel rows of fasteners to the tissue on both sides of a line of incision formed by a body tissue cutting knife assembly included within the fastener cartridge, said fastener cartridge possessing: (a) a fastener holder containing a quantity of fasteners, the fasteners being driven, upon actuation of the fastener cartridge, through substantially parallel rows of apertures defined upon a fastener ejecting surface of the fastener holder; (b) an anvil having a surface opposed to the fastener ejecting surface of the fastener holder and, upon actuation of the fastener cartridge, cooperating therewith to apply substantially parallel rows of fasteners to body tissue positioned between thef astener holder and anvil; (c) means for driving the fasteners through the apertures upon actuation of the fastener cartridge; (d) a tissue cutting knife assembly including (i) a knife element having an upper non-cutting edge and a lower cutting edge, (ii) a knife holder engaging the upper edge of the knife element and (iii) a knife pusher enclosing the knife holder, the cutting edge of the knife element being recessed within the fastener holder in the non-actuated condition of the fastener cartridge and, upon actuation of the fastener cartridge, extending beyond a slot formed between the rows of apertures; and, (e) means for driving the cutting edge of the knife assembly through the slot upon actuation of the fastener cartridge, the improvement which comprises a knife holder having two opposed sides defining at their lower sections a groove therebetween, the knife element being received into, and held in permanent and irreversible locking engagement with, the groove.