An adapter assembly for operably connecting an end effector to an electromechanical surgical instrument includes a drive transfer assembly, a drive member, and a first pusher assembly. The drive transfer assembly includes first and second rotatable shafts. The drive member is operably connected to the first rotatable shaft for transferring rotational motion from the first rotatable shaft to effect a first function and the first pusher assembly is operably connected to the second rotatable shaft for converting rotational motion from the second rotatable shaft to longitudinal movement to effect a second function. The first pusher assembly includes a brake member for rotationally locking the drive member relative to the first pusher assembly.