In vivo assessment of osteoporosis in women by impulse response technique

Osteoporosis in women is increasingly being recognized as an important health issue. The dynamic characteristics of bone which provides quantitative information concerning the mechanical properties of the bone along with measurement of bone mineral density (BMD) can help in the early detection and better diagnosis of osteoporosis. In the present study quantitative assessment of osteoporosis is carried out by impulse response test on the tibial bone of 42 women subjects (age = 44.5±11.6 years). The stress waves are generated in the tibial bone by the impact of impulse force hammer are monitored by accelerometers, and are analyzed in the frequency domain. The natural frequency of stress wave signal is significantly decreased in osteopenia and osteoporosis subjects indicating decrease in mechanical strength of the bone and bone mineral mass. Regression analysis shows a moderately significant negative correlation between natural frequency and age. The natural frequency of stress wave signal shows a good correlation with calcaneus stiffness index (SI) and T-score measured by quantitative ultrasound technique.