Bridging the Commercialization Gap in 3D-Printed Lower-Limb Prosthetics: A Lab-to-Market Framework

Abstract

Additive manufacturing (AM) has significantly reduced costs and lead times in upper-limb prosthetics; however, load-bearing lower-limb prostheses face ongoing challenges in clinical adoption. The widespread use of 3D-printed transtibial and transfemoral sockets is hindered by two primary factors: the structural limitations of single-material polymers under dynamic ground reaction forces and the reliance on traditional, labor-intensive plaster-casting workflows. This paper systematically reviews the mechanical and operational limitations of current 3D-printed prosthetic interfaces and proposes an integrated digital manufacturing framework. Mechanical evaluations from the literature demonstrate that while standard fused deposition modeling (FDM) polymers frequently fail below the ISO 10328 ultimate load standard of 3840 N [11], structural parity with traditional laminated composites can be achieved through finite element analysis (FEA) guided topology optimization, hybrid multi-material architectures (PA12/TPU) [10], and cement-based post-processing reinforcements [1]. Furthermore, to reduce the subjectivity of manual fabrication, this paper outlines a digital pipeline. By combining artificial intelligence (AI) optical scanning for automated geometric design [13] with dynamic pressure mapping [12] to generate zero Poisson's ratio metamaterial lattices, studies indicate that peak interface pressures can be significantly reduced [3]. Ultimately, scaling advanced prosthetics in low- and middle-income countries (LMICs) [15] requires transitioning from decentralized standalone hardware to a closed-loop digital supply chain.