LONGITUDINAL GROWTH OF LONG BONES

Abstract

Knowledge of the growth of long bones had its beginning with the observations of Stephen Hales¹ in 1747. He drilled two holes in the shaft of the tibia of a growing chicken, and when he examined the bone two months later he found that although the shaft had increased 1 inch in length, the distance between the two holes had remained the same. He also observed that most of this length had been gained at the proximal end. He concluded that growth in the length of long bones is accomplished entirely by deposition of new bone at the extremities and that the amount of growth from the two ends is unequal. These observations have been confirmed by similar experiments of many investigators, among them Hunter,² Duhamel,³ Ollier,⁴ Wegner,⁵ Humphry,⁶ Payton,⁷ Kölliker,⁸ Haas⁹ and Gatewood and Mullen.¹⁰ Clinical evidence of unequal