[Changes in the epiphysis and epiphyseal plate in systemic and genetically-induced diseases]

Systemic disorders of the skeleton have either a primary or endogenous, mostly heritable cause like osteochondrodysplasias or they are secondarily or exogenously caused by pathologic influence of the metabolic or endocrine system. The functional unit of growth plate and epiphysis is frequently the target organ of these pathologic influences. The pathogenetic effect on the skeleton is manifested as a disturbance of growth and as an epiphyseal deformity and structural change. Here one must take in consideration the fact that these pathological influences affect not only the epi-and apophyses of tubular bones but also those of the skull, the pelvis and the spine. Because of that and because of the unequal quantitative effect of growth at different growth plates and the chronological different developmental state of the epiphyses, very variable disorders are the result. Disturbances of growth lead to proportional or disproportional short or tall stature. Epiphyseal deformations may have the consequence of contractures and early osteoarthritis. Joint replacement at the hips and knees is inescapable and requires, because of the diminutive skeletal proportions, a special custom -made prosthetic device. Slight epiphyseal deformities, like cone shaped epiphyses, result not so much in functional disturbance but may rather be used as a diagnostic clue. By means of the most typical and important systemic skeletal disorders the pathogenetic principles are discussed.