A surgical instrument includes a handle portion, a shaft housing a firing bar, an end effector comprising an anvil, a lower jaw, and a stapling and severing assembly responsive to a longitudinal closing motion produced by the handle portion and the shaft. The lower jaw is configured to receive a removable cartridge when in an open position. The cartridge includes a housing, a plurality of staples disposed in the housing, and a deck disposed over the plurality of staples. The deck defines apertures, with each aperture being substantially disposed over each staple. The instrument includes a movable buttress that is integral with the housing of the cartridge or integral with the lower jaw of the end effector. The buttress may attach to the anvil and include a portion to receive tissue. The receipt of tissue urges and moves the buttress proximally inwards to further encompass the tissue.