Mondo Description Freeman-Sheldon syndrome (FSS) is a very rare, multiple congenital contractures syndrome characterized by a microstomia with a whistling appearance of the mouth, distinctive facies, club foot and joint contractures. FSS is the most severe form of distal arthrogryposis.

Uniprot Description A form of distal arthrogryposis, a disease characterized by congenital joint contractures that mainly involve two or more distal parts of the limbs, in the absence of a primary neurological or muscle disease. DA2A is characterized by contractures of the hands and feet, oropharyngeal abnormalities, scoliosis, and a distinctive face that includes a very small oral orifice, puckered lips, and an H-shaped dimple of the chin.