Designing and Analyzing a Wrist Splint for Rheumatoid Arthritis Rehabilitation

A wrist splint serves as a device that is designed to immobilize the arm, aiding in the recovery from arm injuries. However, traditional ways of creating splints often overlook the biomechanical sides of arm joint interaction, leading to mechanical fails in splints or potential harm to patients. There is a clinical requirement for an inventive approach to design and optimize custom functional arm splints. This study showcases a technique for splint design that combines topology optimization and additive manufacturing, using biomechanical analysis to achieve advanced customization in terms of comfort, function, and ventilation. Prototypes were made using fused filament fabrication (FFF) in vertical and horizontal orientations, along with powder bed fusion (PBF). Finite element analyses were used to mimic splint movements under maximum patient loads, with validation through physical testing. The function and stiffness of splints made through different ways were assessed and compared. Results show that the created splint meets patients’ biomechanical and functional needs, limiting sagittal movements by 95.7%, coronal movements by 89.8%, and decreasing maximum grip strength by 18.7%. Among the production methods looked at, FFF vertical printing is suggested for general clinical use because of its surface quality, safety, function, and cost-effectiveness.