Lower-limb Prosthetics in the Age of Advanced Solutions: Understanding People’s Needs and Future Benefits

Abstract

The field of lower limb prosthetics has advanced rapidly in the past two decades with increasingly sophisticated devices becoming available each year. Nevertheless, function has yet to be fully restored for people with lower limb amputation. Active microprocessor-controlled prostheses and neuromuscular interfacing can decrease the gap between intact- and prosthetic limbs, providing active assistance, sensory feedback, and intent control where signals from the neuromuscular system are used to implement intended action. While recent evidence suggests that such solutions may improve peoples’ function when compared to earlier technology, device abandonment rates are still a concern, and the impact of novel functions is relatively unclear. Furthermore, current evaluation strategies in the field may be psychometrically invalid, inappropriate for the population, or may not capture the whole range of constructs they are intended to measure. We conducted semi structured interviews, focus group discussions and a contextual inquiry with multiple stakeholders in the field, coupled with a systematic literature search in order to; 1) Explore unfulfilled lower-limb prosthetic user needs; 2) Identify the current and future benefits of advanced lower-limb prosthetic systems, including ones providing active motion, sensory feedback, and intent control; 3) Understand the challenges associated with developing and evaluating such functions; and 4) Assess the relevance of current evaluation methods in light of new developments within the field of lower limb prosthetics. Our results indicate that numerous unmet user requirements may be addressed with neuromuscular interfacing and active motion provided by advanced prostheses. We further identified several challenges in the development and evaluation of advanced prostheses as well as a need for new or updated evaluation strategies. Finally, we present perspectives on factors important for user satisfaction and the actualization of a usable system that reaches end users.