Rickets. Drawing of three pairs of legs (labelled 'a', 'b', 'c'). Pair 'a' and 'b' show the effect of rickets. Pair 'c' show the legs of a rickets sufferer after undergoing an osteotomy. This was a technique pioneered by William Macewen (1848-1924), a Scottish surgeon. He first described the technique in 1880. Rickets or osteomalacia is a deficiency of vitamin D which results in malformation of the skeleton. Vitamin D is necessary for the uptake of calcium from food; without it not enough calcium salts are deposited in the bones to make them rigid. Vitamin D is obtained from certain foods and is also made in the skin when exposed to sunlight.