In vivo determination of the elastic response of bone. II. Ulnar resonant frequency in osteoporotic, diabetic and normal subjects

For pt.I. see ibid. vol.15, 427 (1970) The product of ulnar resonant frequency and length (F a L) was measured for 172 normal men, 265 normal women, and for 28 osteoporotic and 15 diabetic women and was shown to be a function of age; for women after age 55, it decreases rapidly (about 1%/year). The distribution of F a L for randomly selected clinically normal women more than 45 years old is bimodal; this suggests that rapid bone loss is not a universal phenomenon; the so-called senile or postmenopausal osteoporosis appears to be an abnormality and not a normal concomitant of the ageing process. Women with symptomatic osteoporosis exhibit F a L values averaging about 44% less than those of age-matched controls, while diabetic women have values between these two extremes.