Skeletal dysplasia is a general term that refers to abnormal bone and cartilage development. There are over 200 different kinds of skeletal dysplasias, which can manifest in ways ranging from a barely noticeable abnormality to being a severe and lethal condition. The cause for many of the disorders that are defined as dysplasias are not known. Skeletal dysplasias can be observed during fetus development, but are usually not identified until after a child is born.

One baby out of every 4,000 in the US is born with a skeletal dysplasia. The four most common skeletal dysplasias are: Achondrogenesis, Achondroplasia (aka dwarfism – one of the most common forms of non-lethal skeletal dysplasia), Osteogenesis imperfecta, and Thanatophoric dysplasia.