Intramedullary Skeletal Distraction Robot: Novel Design and Optimization of Implantable Lengthening Nail

Leg Length Discrepancy (LLD) is a critical problem which not only impacts the quality of life but also causes other physical ailments such as limping and severe back pain. Most people had non-negligible difference in length their two legs, 0.1% population with differences 20 mm or more are diagnosed limb length. The Ilizarov external fixator commonly used treating LLD conventional therapeutic equipment, often serious complications that cannot be prevented. Therefore, intramedullary leg-lengthening treatment has become popular distraction osteogenesis to eliminate extracorporeal surgery. This paper presents study on design optimization novel electromagnetic-driven Intramedullary Skeletal Distraction Robot (ISDR) robust mechanical stiffness surplus electromagnetic driving force. Compared PRECICE, split structure ISDR eases optimal manufacturing difficulties strengthen stiffness, configuration allows improving force by adjusting Permanent Magnet Brushless Direct Current (PMBLDC) motor parameters. ISDR, implanted medullary cavity, Von-Mises stress 952.15 MPa, first mode natural frequency 28.823 Hz indicating it can withstand load during walking gait phases. On hand, encounters resistance from muscle fibers, an average torque 9 Nmm ensures its distraction. Based results, proven secure reliable after treatment, significantly reduce lifestyle disruption medical complications.