II. The prevention of the development of rickets in rats by sunlight

Abstract

In June, 1919, Huldschinsky 1 reported that the ultraviolet ray exerted a curative action in rickets. The criterion on which he relied was the evidences furnished by the X-ray of calcium deposition at the ends of the long bones. He found that there were definite signs of calcium deposition after four weeks of treatment and that at the end of eight weeks healing was almost complete. In May, 1920, Huldschinsky 2 again reported the curative effects of treatment with the ultraviolet ray in rickets in a series of thirty children, aged between one and one half and six and one half years, who exhibited all clinical manifestations of the disease. In all, healing was accomplished after twenty-two to twenty-six treatments covering a period of two months. In April, 1920, Putzig 3 corroborated the findings of Huldschinsky. He obtained cures by means of the quartz lamp in premature infants suffering from rickets. In July, 1920, Riedel 1 further confirmed Huldschinsky's findings in a series of one hundred children suffering from rickets. In June, 1921, Hess 2 confirmed Huldschinsky's findings in a series of six cases.

The favorable influence of sunlight in rickets has been recognized by some students of the disease for a long time, notably by Palm 3 (1890), and experimental evidence of its beneficial effect on mineral metabolism in the puppy has been furnished by Raczynsky 4 in 1912. Huldschinsky made use of sunlight together with the ultraviolet ray in two cases of his series and Riedel relied on treatment with sunlight in some of his cases, supplementing with the quartz lamp ray only on sunless days. Hess 5 was the first, so far as we are aware, to demonstrate, by means of the radiograph, that sunlight alone exerts the same curative action as the ultraviolet ray.