Research & Development of 3D Printing Orthotic Insole and Preliminary Treatment to Five Leg Length Discrepancy Patients

Background : Leg Length Discrepancy (LLD) can cause abnormal posture, muscle and joint pain and difficulty in walking on human body. The common treatment is to use shoe lift on the side of short leg, but the effects were not satisfactory. Through the research and development of 3D printing orthotic insole initially applied to LLD patients to see if it can effectively improve the above symptoms. Methods: 1. Research and development of 3D printing orthotic insole: (1) foot scan and data acquisition (2) insole software modeling (3) 3D printing insole using TPU materials (4) post-processing of finished product. 2. Clinical observation: for LLD patients who meet the research criteria, to customize insoles and require them to wear it while walking, to conduct general inquiries and functional initial evaluation prior to wearing the insole, including pain assessment, gait analysis, health questionnaire, and final evaluation after 12 weeks’ wearing. Results: In total five patients have completed the research. Before treatment, patients reflected they had various degrees of lower limb joint pain and lower back pain while walking, after 12 weeks’ of wearing the insoles, the pain were alleviated. The stride frequency, stride and pace of five patients were improved, the lower limb support phase and swing phase of three patients became normal apparently; Conclusion: The 3D printing orthotic insoles is made with clear procedures and practical operability. LLD patients have a better therapeutic effect in relieving muscle and joint pain and improving gait by wearing 3D printing insoles.