3D printed transtibial prosthetic sockets: A systematic review

Abstract

The prosthetic socket, which transfers load from the residual limb to the prosthesis, is an integral part of the prosthesis. 3D printing has emerged as a potentially viable alternative to traditional fabrication for producing sockets that effectively transfer loads. We conducted a systematic review to better understand the current state of this newer fabrication method, with a focus on the structural integrity of 3D printed sockets and factors that can affect the strength of 3D printed sockets when tested using ISO 10328 standards. Literature searches were carried out in five databases (PubMed, Scopus, CINAHL, Web of Science and Google Scholar). Two reviewers independently performed the literature selection, quality assessment, and data extraction. A total of 1023 unique studies were screened in accordance with inclusion and exclusion criteria. Of 1023 studies, 12 studies met all inclusion criteria, with failure data for 15 3D-printed sockets and 26 standard laminated sockets. Within 3D printed sockets, the addition of composite materials such as carbon fiber particles and distal reinforcement using a compositing infill technique appears to improve socket strength. In light of the considerable amount of heterogeneity between studies in terms of materials and alignment used, the absolute values for failure could not be established for 3DS nor directly compared between 3DS and LCS. However, there is some evidence that the probability of a failure at a given load may be comparable between 3DS and LCS up to the P8 level. For all sockets, whether a laminated composite socket or a 3D printed socket, failure mainly occurred at the distal end of the socket or the pyramid attachment, which is consistent with the ISO testing protocol. Improving the strength of the 3D printed sockets through design modifications at the distal end and implementing emerging printing technologies could help to promote 3D printed sockets as a viable option, particularly when cost or access to care is limited.

Exploring the Future of Prosthetics and Orthotics: Harnessing the Potential of 3d Printing

“…Regardless, our systematic review results did show that 3D printed sockets were trending towards producing similar failure forces as those observed in laminated sockets. 5 We complemented this review with empirical data collected by our group in which we performed ultimate failure testing of 3D printed composite sockets using some of the latest filaments available. For 3D printed sockets, three different material filaments were used: PETG (Filament Innovations, Pennsylvania, USA); polycarbonate or PC (Polymax-PC, Polymaker, Changshu, China); and co-polymer polypropylene or CPX (Filament innovations, Pennsylvania, USA).…”

Assessment of 3D printed mechanical metamaterials for prosthetic liners

“…3D printing has been exploited as a promising means of producing prosthetic sockets 13 and moulds 14 for custom silicone liners, as it can accommodate complex residuum shapes in design and manufacturing to an appropriate level of accuracy. 15 Advancements in additive manufacturing technology means that a more comprehensive range of elastomeric materials exhibiting a wider range of stiffness, as compared with that of silicone, can now be exploited.…”