The Application Study of Specific Ankle-Foot Orthoses for Stroke Patients by 3D Printing Somos NeXt

Objective: To investigate the effects of specific ankle-foot orthoses (AFOs) fabricated by 3D printing Somos NeXt on patients with stroke. Method : The ankle and foot were scanned by Artec 3D scanner. The model was performed with finite element analysis (FEA) using the software Abaqus to optimize the structure. Based on the structural optimization, AFOs were fabricated by 3D printing technique of Somos NeXt. Gait parameters were measured using the Gait Watch system. Seven sensors were bound to the sacrum, anterior side in the middle segment of the bilateral femoral femur, the median side at the proximal end of the bilateral tibia, and dorsal part of the bilateral foot. Results: The AFOs fabricated by 3D printing Somos NeXt significantly improved the temporal-spatial parameters including velocity (20.75 vs. 17.38 cm/s) and stride length (47.88 vs. 43.63 cm), as well as increased cadence (52.5 vs. 48.75 times/min), while slightly decreased gait cycle (2.57 vs. 2.80 cm) and double limb support phase (34.00 vs. 37.13%). The AFOs also improved symmetry parameters such as the step length difference (9.75 vs. 15.25 cm), step length ratio (1.87 vs. 3.98), and swing phase ratio (0.99 vs. 0.75). Conclusion: The AFOs fabricated by 3D printing Somos NeXt have a significant effect on the improvement of velocity and stride length in patients with stroke.