A pulsed Doppler ultrasonic system for making noninvasive measurements of the mechanical properties of soft tissue.

In response to the need for a more precise means of predicting the interaction of a prosthetic socket with an amputee's residual limb, a gated Doppler ultrasonic motion sensing system was devised for making noninvasive measurements of the elastic modulus of soft tissue in vivo. Ultrasound was chosen for its ability to indicate the viscoelastic behavior of biological materials without damaging tissue. The system consists of a holding jig to support the limb being tested, a tissue vibrator, and an ultrasonic transducer to monitor the motion of the tissue. The ultrasonic transducer is controlled by an external computer to control the depth at which the sensor is measuring tissue displacement. This ultrasonic measuring technique provides as much information as more conventional techniques, but with more convenience and fewer restrictions.