The Effect of Soft Tissue on Measurements of Vibrational Bone Motion by Skin-Mounted Accelerometers

The effect of the soft tissue between bone and a preloaded skin surface accelerometer was studied in vivo by comparing its output with the output of an accelerometer connected directly to the bone by a needle through the soft tissue. A 34-g skin surface accelerometer gave an output with little resemblance to the bone motions, appearing to oscillate at its resonant frequency on the soft tissue. A 1.5-g skin surface accelerometer showed nearly identical output to the bone acceleration.