Progressive pseudorheumatoid arthropathy (dysplasia) of childhood (PPAC; PPD) presents as spondyloepiphyseal dysplasia (SED) tarda with progressive arthropathy and is described as a specific autosomal recessive subtype of SED. The disease is Monarch Disease Ontology identifier MONDO_0008827 (progressive pseudorheumatoid arthropathy of childhood). Also known as: spondyloepiphyseal dysplasia tarda-progressive arthropathy syndrome.