Fibrodysplasia ossificans progressiva (FOP): What you need to know.
Fibrodysplasia ossificans progressiva FOP: A rare disease but dramatic genetic disorder that turns muscles, tendons and ligaments into bone. Medical Definition of Fibrodysplasia ossificans progressiva (FOP) Disease Fibrodysplasia ossificans progressiva (FOP) is a condition in which bone grows outside the skeleton. Abnormal bone growth replaces connective tissue, including tendons and ligaments. FOP is caused by …