University of Washington

Daniel C Abrahamson

Kirk Watson Beach

Joan E Sanders

Katheryn J Allyn

Timothy Myers

Ellen L Lee

Daniel S Harrison

Santosh Zachariah

Changes in the volume of residual limbs on which prosthetic sockets are worn can be measured based on bioimpedance measurements along one or more segments of the limb. A current at an appropriate frequency (e.g., in the range from 1 kHz to 1 MHz) is injected at two current electrodes that contact the skin of the residual limb. The voltage at the voltage electrodes disposed between the current electrodes is measured and using an appropriate model, the change in the segmented volume of the limb can be determined during periods of different activity and at different times during the day. This information can be used for assessing the fit of the socket and can also provide a feedback signal for automatically controlling volume management devices, to ensure a more comfortable fit when the volume of the limb is changing.

Measurement and use of in-socket residual limb volume change data for prosthetic fitting

Growing community of inventors

Seattle, WA, United States of America

Daniel C Abrahamson