Pilot Test of a Definitive Prosthetic Socket Made with 3D Printing Technology

ABSTRACT Introduction Additive manufacturing (also known as 3D printing) as a fabrication method is ideally suited to merging the organic shapes of human anatomy with engineered components. Many early adopters are exploring the application of these technologies for the fabrication of 3D-printed sockets, but questions remain regarding the ability to fabricate strong, well-fitting definitive sockets. The goal of the present study was to examine the real-world effect of using 3D-printed sockets with regards to mobility, comfort, balance confidence, and user acceptance. Materials and Methods Nine veterans with transtibial amputations participated in the study, three each using pin, sealing sleeve, or seal-in liner for suspension. Participants had their conventional definitive socket duplicated using 3D printing. When the 3D-printed socket was ready, using their conventional socket, participants performed a 2-minute walk test, followed by socket comfort score and rating of perceived exertion (10-point scale), Prosthetic Limb Users Survey of Mobility, Activities-Specific Balance Confidence, select subscales of the Prosthesis Evaluation Questionnaire, and the Amputee Body Image Scale–Revised. After completing the baseline data, participants were fitted with the 3D-printed socket and, after using it for 2 weeks, we repeated the data collection. Results Three participants were not able to complete the study. No large differences were observed for any of the measures. Participants were generally satisfied with the fit of the 3D-printed sockets, but there were challenges with getting the 3D-printed sockets to support elevated vacuum with the sealing sleeve and seal-in liner suspension methods. Conclusions No differences in performance or user acceptance were identified for pin suspension, but the 3D-printed sockets were not able to reliably support suction or elevated vacuum; further development will be needed before they are ready for clinical application. Clinical Relevance The present study has demonstrated the ability to achieve satisfactory fit and outcomes using 3D printing to fabricate definitive prosthetic sockets, but the printing method was unable to deliver consistent air-tight sealing for suction or elevated vacuum suspension. Other 3D printing methods and some secondary processing steps may be able to correct this deficiency.