Scan and 3D Print: Magnetic Resonance Imaging‐Guided, Monolithic Desktop Fabrication of Highly Biomimetic Skeletal System of the Human Hand

3D-printed human-inspired hands, while visually similar to their biological counterparts, often lack key features that enable the unique capabilities of human hands. In this research, a framework for desktop 3D printing patient-specific human hands with a high functional level of biomimicry is presented. Magnetic resonance imaging (MRI) data are used to create computer aided design (CAD) models replicating key features of the skeletal system, including soft joints, ligaments, and volar plates, which are critical for mimicking the motions and functions of natural hands. The entire hand, consisting of rigid and soft segments, is monolithically 3D-printed using a commercial, inexpensive (≈€ 500) desktop multimaterial printer, eliminating the need for assembly and expensive 3D printers. The proposed MRI to Desktop 3D printing approach contrasts with the state of the art, where high biomimicry is achieved through a multistage assembly process and expensive 3D printing setups. The resulting hand shows several unique behaviors of natural hands, including an opposable thumb moving across the palm, improved resistance at bone–joint interfaces, high life cycle, constrained bending, absorption of perpendicular loads, high range of coordinated, bioinspired motion, and grasping capabilities. The proposed approach can be potentially used to 3D print prosthetic hands tailored to individual needs, leveraging patient-specific digitally created MRI data.