Yup. As horrific as it is to imagine, caulking has been used on several occasions. One recent case (Apryl Brown) led to a staph infection and the woman having to have her lower arms and legs amputated.
Horrible stuff.
It seems as if the compulsion to have an unnaturally large rear end is in the same general class of mental illness as the urge to mutilate oneself so as to look like the opposite sex.