Impact of Prosthetic Liner Materials on Thermal Comfort and Bacterial Growth at the Residual Limb–Socket Interface: A Systematic Review

As the main point of contact between the residual limb and the prosthetic socket, prosthetic liners are essential for the comfort, suspension, and tissue protection of the residual limb. Lower-limb prosthesis users typically encounter liner-related issues like excessive sweat, thermal discomfort, bacterial growth, unpleasant odor, and skin irritation despite the device's broad clinical use. The enclosed, damp liner-socket environment and the repeated mechanical loading that occurs during daily operations are the main causes of these issues. This systematic review evaluates the effects of prosthetic liner designs and materials on residual limb–socket interface bacterial growth and thermal comfort. A systematic literature search was conducted in PubMed, Scopus, and Google Scholar following PRISMA guidelines. Following screening and eligibility evaluation, 20 studies published between 2005 and 2025 were included from the original pool of 121 records. Laboratory research, clinical trials, and review papers analysing liner material qualities, thermal behaviour, hygiene concerns, and design advances, such as customizable and affordable liners, made up the chosen studies. The results show that the thickness, surface properties, and composition of the liner material have a major impact on heat transfer, bacterial adhesion, and contact biomechanics. While antimicrobial surface changes indicate a temporary decrease in bacterial growth, the majority of prosthetic liners exhibit low thermal conductivity that contributes to heat accumulation. Overall, the strength of the evidence is low to moderate, as the majority of the available data comes from laboratory and small clinical investigations. This review highlights the potential importance of integrated prosthetic liner solutions that address biological safety, thermal control, and mechanical performance to improve residual limb health and long-term prosthesis use.