The current state of 3D-printed orthoses clinical outcomes: a systematic review

Introduction: 3D-printing is an emerging technology that is used in the manufacturing of orthotic devices. 3D-printing has many advantages such as improved fit, comfort, effectiveness, and patient satisfaction. While some challenges like durability and material selection remain, the aim of this systematic review is to provide a comprehensive evaluation of the clinical outcomes of 3D-printed orthoses. Methods: A search was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines across six databases (PubMed, Web of Science, EBSCO, Scopus, Cochrane Library, and Sage). Studies on 3D-printed orthoses in human rehabilitation that focused on the clinical outcomes of the device were included. While studies lacking clinical data, 3D-printing details, or focusing on traditional manufacturing methods were excluded. Finally, the risk of bias was assessed using the modified Downs & Black Checklist. Results: A total of 1279 studies were identified, with 62 meeting the inclusion criteria. The included studies assessed different 3D-printed orthotic types, including insoles, ankle foot orthoses (AFOs), spinal orthoses, upper-limb orthoses, and helmets. The main clinical outcomes that were analyzed are gait parameters, functional performance, radiographic measurements, comfort, fit, and effectiveness. Studies on 3D-printed insoles demonstrated effective plantar pressure redistribution, and increased comfort. While studies on 3D-printed AFOs showed improvements in gait symmetry and mobility. 3D-printed spinal orthotics showed reductions in Cobb angles and enhanced postural stability in scoliotic patients. While 3D-printed upper-limb orthoses found improved grip strength, spasticity management, and user satisfaction. Finally, studies on 3D-printed helmets for cranial deformities demonstrated improved fit and reduced treatment duration. Conclusion: 3D-printed orthoses can enhance gait parameters, functional performance, comfort, fit, and effectiveness, compared to conventional methods. However, limitations such as small sample sizes, lack of standardized assessment methods, and durability concerns must be addressed through further research.