Structural integrity of 3D-printed prosthetic sockets: Experimental study for paediatric applications

Abstract

Due to unique patient characteristics, prosthetic sockets cannot be included in a standardised testing protocol as the rest major parts of the prosthesis. This makes the mechanical assessment of the socket a difficult process, which still remains crucial, especially nowadays, when new manufacturing technologies, such as additive manufacturing, are gaining ground in the field. In this study, a prototype testing rig was developed according to BS EN ISO 10328 standard, able to recreate the loading conditions of the early stance of the amputee gait on a paediatric transfemoral socket. The load requirements suggested in the standard were recalculated for the case of a 14-year-old male user with their weight in the 98th percentile. A variety of above-knee prosthetic sockets were produced with PLA and carbon-fibre reinforced nylon, using a commercial 3D printer. The sockets were tested under compressive load employing a plaster limb manikin. Video image processing was used to accurately capture the load-displacement relation of the sockets.

Keywords

• Mechanical testing
• Prosthetic
• 3D printing
• Failure