A group of rare, autosomal recessive inherited disorders characterized by a constricted thoracic cage, short ribs, and a 'trident' appearance of the acetabular roof. Polydactyly may or may not be present. Other abnormalities include cleft lip and palate and abnormalities of the brain, eye, heart, liver, pancreas, intestine, kidney, and genitalia. The disease is Monarch Disease Ontology term MONDO_0009894 (short-rib thoracic dysplasia 6 with or without polydactyly). Also known as: Majewski syndrome, SRPS2A, SRTD6, polydactyly with neonatal chondrodystrophy type II, polydactyly with neonatal chondrodystrophy, type II, short rib-polydactyly syndrome type II, short rib-polydactyly syndrome type IIA.