FIELD: medical equipment.SUBSTANCE: group of inventions relates generally to circular staplers and, more particularly, to an alignment configuration for aligning an anvil assembly and a staple driver of a circular stapler. Stapling reload assembly for a circular stapling instrument includes a casing, staple holder attached to the casing, staple driver, and an anvil assembly. Staple driver includes a driver alignment surface, at the same time staple driver is receivable within the casing and is configured to move within the casing from a pre-fired position to a fired position. Anvil assembly includes an anvil base surface, an anvil alignment surface, and a staple forming surface, anvil shaft and metal shaft detachably connected to anvil shaft. Anvil alignment surface is configured only on anvil shaft and extends from the top of the anvil shaft to the bottom part of the anvil shaft, anvil base surface is configured to move from an open position away from the casing to a closed position adjacent the casing. anvil alignment surface is configured to mate with the driver alignment surface to rotationally align the staple forming surface with the staple holder, when the anvil base surface is in the closed position. Circular stapling instrument comprising: handle, firing trigger, anvil control member, staple holder attached to the casing. Staple driver disposed within the casing and moveable, when the firing trigger is fired, within the casing from a pre-fired position to a fired position. Anvil base is moveable, using the anvil control member, from an open position away from the casing to a closed position adjacent the casing wherein when the anvil base surface is in the closed position the anvil alignment surface mates with the driver alignment surface and rotationally aligns the staple forming surface with the staple holder.EFFECT: inventions provide reliable alignment between anvil plate and driver to reduce possible variability.12 cl, 47 dwgГруппа изобретений относится