Progressive pseudorheumatoid dysplasia

A rare case of progressive pseudoheumatoid dysplasia (PPD) in a 9-year-old girl is presented. Clinically, chronic painless swollen joints, accompanied by progressive motion restriction and progressive walking difficulties, we re found. Radiologically, there was enlargement of the epimetaphyseal porti ons of the large joints, metacarpal heads, and phalanges, and generalized p latyspondyly with irregular delineation of the endplates of the vertebral b odies. The radioclinical features at the peripheral joints were originally misdiagnosed ad juvenile rheumatoid arthritis (JRA), and the structural spi nal abnormalities were neglected and interpreted as Scheuermann's disease. However, the absence of active inflammatory parameters argues against JRA, whereas the low age of onset of the irregularities at the vertebral endplat es is an arhument against the diagnosis of Scheuermann's disease. The combi nation of the dysplastic abnormalities of the spine, with platysponsyly and Scheuermann-like lesions at an unusally low age of onset, and radiological features mimicking JRA of the peripheral joints, is the clue to the diagno sis of this rare autosomal-recessive disease. This case is the first to doc ument the MRI features of PPD of the spine.