[Effect of fractures on the juvenile epiphysis].

In a clinical and experimental study two factors have been found to be most important for the increase of growth after fractures in childhood: 1. Trauma leads to changes of blood circulation in the epiphysis. Changes in oxygen tension cause morphometric alterations of cellular and intercellular constituents of the plate as well as measurable changes in thickness of the plate and length of the cartilage columns. These changes are relatively uniform and nearly independent of the kind of fracture and its treatment. Growth stimulation by fracture alone is moderate, limited to the time of fracture healing and hardly influenced by implantation of metallic material for osteosynthesis. 2. Angular deformity stimulates the epiphyseal plate to spontaneous correction. This correction is mostly stimulated by the change of pressure caused by the muscular coat and only minimally by static load. Correction of angular deformity can only happen under simultaneous increase in longitudinal growth, as long as pressure in the plate is changed. If angular deformity does not lead to changes in pressure by muscular tension on the concavity of the fracture (e.g. recurvation of tibia, varus in supracondylar fracture of humerus, torsion deformity of long bones) no stimulation of the epiphyseal plate will occur. In these cases the increase of growth is insignificant.