Osteochondrodysplasia is a form of osteoarthritis) affecting skeletal development, growth and maintenance of cartilage and bone. The disease is thought to be inherited as an autosomal dominant disorder. There are more than 100 known genetic skeletal osteochondrodysplasias, many of which are congenital. The cartilage and bone abnormalities have been reported in both humans and animals with dwarfism and degenerative joint disease. In achondroplasia, ossification that occurs in and replaces cartilage (enchondral ossification) of all long bones is retarded, resulting in shortened and deformed limbs. Hypochondroplasia is similar to achondroplasia; however, the condition is less severe.