For people with lower-limb amputations, socket fit management can be a never-ending process of monitoring. Many users find that adjustments are burdensome, as it draws their attention away from other responsibilities and adversely affects their quality-of-life.
Adaptive sockets are intended to sense changes in socket fit and make proper adjustments before the prosthesis user senses an issue. An open access study published in Scientific Reports presented results from take-home testing of a motor-driven adaptive socket that automatically adjusted socket size during walking.
A socket fit metric was calculated from inductive sensor measurements of the distance between the elastomeric liner surrounding the residual limb and the socket’s inner surface. A proportional-integral controller was implemented to adjust socket size. When tested on 12 participants with transtibial amputations, the controller was active a mean of 68 percent of the walking time.
In general, participants who walked more than 20 minutes per day demonstrated greater activity, less doff time, and fewer manual socket size adjustments for the adaptive socket compared with a locked nonadjustable socket and a motor-driven socket that participants adjusted with a smartphone application, the study found.
Nine of 12 participants reported that they would use a motor-driven adjustable socket if it were available as it would limit their socket fit issues. The size and weight of the adaptive socket were considered the most important variables to improve, according to the study.
