A cartridge assembly (710) is disclosed. The cartridge assembly comprises a cartridge housing (720) and a cartridge (740). The cartridge housing has a plurality of biasing members (722) thereon. The cartridge is configured for reception at least partially within the cartridge housing. The cartridge includes a plurality of fasteners at least partially therein. The cartridge has a plurality of pockets (742). Each fastener is ejectable from a corresponding pocket. The cartridge has a plurality of chambers (744), and each chamber is adjacent a pocket and configured to store at least one fastener at least partially therein. At least one fastener is movable from the chamber to the pocket. The cartridge includes a plurality of pushers (800) having a first cam surface (806) and a secod cam surface (808), where each pusher is configured to engage at least one corresponding fastener. The instrument further comprises a driver (820) having a lower portion (826) and an upper portion (824), the upper portion contacting the ssecond cam surfaces sequentially when the driver is moved in the proximal direction and the lower portion contacting the first cam surface when the dirver is moved in distal direction.
