Fabricating Sockets With Distance Sensors for Monitoring Prosthesis Use and Socket Fit

Abstract

Introduction In previous research, we developed and implemented novel inductive sensors to detect the motion of a prosthesis user’s residual limb in the prosthetic socket. Materials and Methods In this article, methods for installing the inductive sensors within the wall of a prosthetic socket are described. The sensors are flexible, 32 mm in diameter, and less than 0.2 mm thick. Two sensor placement configurations are described, one to monitor prosthesis use and the other to monitor socket fit. Results The sensors are installed after the inner resin layer of the socket is completed. Installation of the sensors increases the fabrication time over that of a traditional laminated socket by about 6 hours. Conclusions A systematic and repeatable method for manufacturing prosthetic sockets with embedded distance sensors was developed to facilitate adoption of this technique. Clinical Relevance Dissemination of the fabrication technique to install inductive distance sensors in sockets may facilitate clinical research investigation using this new technology, ultimately improving decision making for treatment, diagnosis, and prognosis of health issues faced by people with lower-limb amputation.

Distal weight bearing in transtibial prosthesis users wearing pin suspension

“…Each socket was fabricated with six thin inductive sensor antennae placed within the socket wall. Sensors were positioned at anterior proximal, anterior mid-limb, anterior distal, posterior lateral mid-limb, posterior medial mid-limb, and posterior distal locations as shown in Supplementary Presentation S2 , using methods detailed in prior work ( 9 ). The sensors measured the distance to a trace amount of iron powder placed in the elastomeric liner just under the fabric backing.…”