AbstractsChemistry

Rickets is a condition made manifest by defects in the calcification of growing bones. The changes in the bones result in outward symptoms which may be recognized clinically, such as, enlargement of the wrists, knees and ankles, bowed legs, and the rachitic rosary. In normal growth of bone, there appears, on the diaphysial side of the narrow cartilage, a continuous layer of empty cartilage cells forming an almost straight line. Growth of the bone is obtained by the degeneration of a new row of cartilage cells and ossification of the former row. In rickets, the degeneration of the cartilage cells ceases and consequently there is no ingrowth of capillaries and ossification cannot occur. Since this cessation of degeneration does not affect all cells at the same time, the epiphysial cartilage, on the diaphysial side, becomes irregular. The prevention and cure of rickets may be brought about by the inclusion of vitamin D in the diet provided calcium and phosphorus are also present in adequate amounts. When vitamin D is fed to rachitic animals, ossification begins again in the empty cartilage cells. A new row of empty cartilage cells will generally appear within twenty-four hours of ingestion of the vitamin. [...]