POLYEPIPHYSEAL DYSPLASIAS AND CHONDRODYSPLASTIC RHEUMATISM

The hip is the commonest site of polyepiphyseal dysplasia. These genot ypic diseases are characterised by the presence of a moderate dysmorph ic syndrome associated with developmental anomalies of the epiphyses. Metaphyseal and spinal alterations are absent or minor. The joint symp toms associated with these diseases have a polymorphic clinical and ra diological expression . Osteoarthritis, the commonest manifestation, h as several specific signs which distinguish it from << common >> osteo arthritis : early onset, severity, dissemination and involvement of no n-weight-bearing joints. Osteochondromatous formations, related to fra gmentation of the epiphyses, are present in approximately one third of patients and may sometimes be responsible for joint locking. Progress ive tendon retraction of the extremities has been exceptionally report ed. Recurrent acute arthritis is more frequent, affecting joints with a radiological appearance often similar to that of metabolic joint dis ease with subchondral bone changes and occasionally calcified margins.