Bone Quality Assessment Using MEMS Accelerometer

Bone Mineral Density (BMD) is the amount of mineral per square centimeter of bone. Osteoporosis is defined as a systemic skeletal disease characterized by low bone mass and micro architectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture The prime motive of our work is to produce a cost effective medical instrument of the Bone Mineral Density (BMD).The developed instrumentation for assessing bone quality utilizes the principle of impulse response method. Our device consists of an automated hammer which knocks in the medial side of the proximal tibia. The stress wave is propagated through the bone and it is picked up by two triaxial MEMS accelerometers. Using this setup the acceleration magnitude has been measured for various subjects and the corresponding signals were obtained. The acquired signals are fed into the computer. We have collected the data from ten subjects with two different age groups and sex and found that the acceleration value obtained in the y-axis of second MEMS accelerometer of above 35 age is higher compared with the subjects below 35 years old. From the acquired and analyzed data, we found there is a significant change exists among the different age groups.