Mechanical hemolytic anemia is a form of hemolytic anemia due to mechanically induced damage to red blood cells. Red blood cells, while flexible, may in some circumstances succumb to physical shear and compression.[1] This may result in hemoglobinuria. Some forms are self-inflicted (march hemoglobinuria),[2] if not intentionally, through repeated mechanical motions. Examples include marathon running, prolonged marching, and bongo drumming.[3] The other common form, called microangiopathic hemolytic anemia, is a chronic condition due to prosthetic heart valves.[1]