ULTRASOUND VELOCITY OF THE TIBIA IN NORMAL GERMAN WOMEN AND HIP FRACTURE PATIENTS

One of the latest developments in quantitative ultrasound (QUS) is the measurement of the speed of sound (SOS) of cortical bone of the midti bia. To determine the diagnostic validity of this method we measured 1 50 healthy women aged 22-94 years. Additionally, we report on first re sults of patients with hip fracture. Precision in vivo of the tibial Q US expressed as the percentage coefficient of variation (CV) was 0.39% for the first day and 0.45% after repositioning the second day (mean CV = 0.42%). No significant dependency of tibial SOS was found with we ight, height, and body mass index in pre- and postmenopausal women. Th ere was a significant decline of SOS with age in postmenopausal women (SOS = 4225 - 5.3 age, r = -0.46, P < 0.001), whereas premenopausal wo men showed no decline (SOS = 3906 + 1.3 age, r = 0.13, ns) Mean SOS va lues of premenopausal women were significantly higher than those of po stmenopausal women (3960 +/- 78.7 m/second and 3898 +/- 120 m/second, respectively, P < 0.001). Postmenopausal women on estrogen substitutio n had significantly higher mean tibial SOS values than age-comparable postmenopausal women without estrogen substitution (3980 +/- 99 m/seco nd and 3869 +/- 100 m/second, respectively, P < 0.001). Significant di fference between age-matched healthy women, n = 11, and hip fracture p atients, n = 13, expressed as z-score of -1.4 SD was found. In conclus ion, tibial QUS declines with age and detects higher values in premeno pausal women and postmenopausal. women on estrogen substitution and lo wer values in hip fracture patients. Further prospective studies are n eeded to clarify its role in fracture risk assessment.