3D printing technology applied to orthosis manufacturing: narrative review

Recently, three-dimensional (3D) printing technology has gradually been applied to the field of orthoses. This narrative review aimed to investigate the effect of 3D printed orthoses compared to conventional orthoses (non-3D printed orthoses). We searched MEDLINE for articles published up to July 27, 2020, and the main search phrases for identifying related articles were "3D printed orthosis", "3D printed orthoses", "3D printed braces", "3D printed splints", "3D printing orthosis", "3D printed orthoses", "3D printing braces" and "3D printing splints". We included articles that applied 3D printed orthoses to patients or healthy participants and excluded those not written in English, conference abstracts or presentations, and reviews. A total of 237 papers were identified, and qualifications were evaluated based on the title, abstract, and full text. A total of 22 articles were finally included in the analysis. The 3D printed orthoses showed similar or superior effects on biomechanical parameters and kinematic parameters such as wrist-hand function, wrist spasticity, arch height index, foot plantar pressure, and joint range of motion (ROM). In addition, 3D printed orthoses had high satisfaction and comfort compared to conventional orthoses. We believe that 3D printed orthoses can replace conventional ones, and they are expected to gain more popularity in the future.