What is Ultrasound:
We know that when an object vibrates it makes a sound. Scientists refer to the number of vibrations per second as the frequency of sound, which is measured in hertz. Our human ears can hear sound waves with a frequency of 20 to 20,000 hertz. We cannot hear sound waves when they vibrate at a frequency greater than 20,000 Hz or less than 20 Hz. Therefore, we call sound waves with a frequency higher than 20,000 Hz "ultrasound". The frequency of ultrasound waves used for medical diagnosis is usually 1 to 5 megahertz.
Using the speed of sound wave conduction and amplitude attenuation can reflect the amount of bone mineral content and bone structure and bone strength of the situation, the instrument used for ultrasound bone densitometer.
The amount of bone is calculated based on the speed of propagation of ultrasound waves within the bone tissue, the degree of attenuation, and may also provide the quality of the bone.