ABSTRACT
Osteoporosis, osteomalacia, and hyperparathyroidism are the several major disorders that are usually discussed under the heading of metabolic bone disease. During metabolic adult life bone formation keeps up with bone resorption, and thus the skeleton is stable. However, in older people and in certain other metabolic situations, bone formation becomes less, whereas bone resorption remains normal. Osteoporosis is a major health problem affecting over 20 million patients in the United States alone. Various attempts to measure the bone mineral density using physical methods have come and gone, although single-photon absorptiometry devices remain in widespread use in renal dialysis centers. These machines are inexpensive and easy to use; however, they really only measure the cortical bone mineral in the peripheral arm bones, so are of no use in the diagnosis and follow-up of patients with early osteoporosis. In congenital hypoparathyroidism, short metacarpals and metatarsals can be seen, and in fact premature closure of the epiphyses can occur.
