II. Quantitative Measurement of Bone Mineral Content in Normal Adult Bone

Abstract

This paper describes a series of quantitative measurements of bone mineral content in the limbs of normal healthy adults. The object of these measurements was to determine the range of variation in normal people, and the extent to which various factors influence the bone mineral content. Measurements were made at the lower end of the ulna and on the posterior process of the calcaneum. The method used to measure bone mineral content in the lower ulna has been described previously (Keane, Spiegler and Davis, 1959). For the measurement of the mineral content of the posterior process of the calcaneum the method has been modified and is illustrated diagrammatically in Figs. 1 and 2. A Perspex tank, 12 cm wide, 35 cm long and 20 cm deep is used. In the tank are placed two movable Perspex bridges which support the foot 6 cm from the bottom. The foot is placed with its lateral border in contact with the side of the tank; in this way the long axis of the calcaneum lies at 90 deg. to the X-ray beam. The patient is seated with the lower leg vertical to avoid inversion or eversion of the calcaneum. The standard wedge is fixed vertically in a movable block of Perspex of the same height as the foot supports, so that the centre of the wedge can be placed immediately behind the heel.