Stapedotomy and stapedectomy are operations done to improve hearing. You may have learned the 3 bones behind the ear drum as the hammer, anvil, and stirrup. Their real names are malleus, incus, and stapes. The stapes is supposed to move like a piston in a motor, but if bone grows between it and the surrounding bone it can't move well. This causes hearing loss. These operations either bypass the stuck part of the stapes(stapedotomy) or remove it (stapedectomy) to improve hearing.