Specific design elements of motorcycles that have been under scrutiny include the shape of the top gas tank or items placed on it which can contribute to urogenital or pelvic injuries in a crash. In cases of a single-rear brake-light, its failure leaves other drivers without notification that the motorcycle is stopping. Despite the focus on the head and helmet protection, it is possible for handlebars to castrate males in accident and damage done to the lower spine can leave men alive but paralyzed. Motorcycle accidents are risk factor for injuries to testicles, delicate reproductive organs that are contained in thin skinned sac outside the body in males. In collisions between testicles and gas tanks, testicle dislocation can occur where they are pushed into the lower abdomen. Motorcycle accidents can cause genitourinary trauma which may result in pelvic pain and various other symptoms depending on the nature of the damage.