Realistic 3D-Printed Lumbar Spine Model for Non-cadaveric Surgical Training: A Proof of Concept Study

Surgical simulation plays a crucial role in modern neurosurgical training, allowing surgeons to develop and refine their skills in a controlled and risk-free environment. Traditional methods, such as cadaveric dissections, and virtual reality (VR) simulations more recently have their advantages and limitations. While cadaveric models offer high anatomical accuracy, they are expensive, difficult to access, and non-reusable. VR simulations provide customizable training experiences but lack the realistic haptic feedback necessary for hands-on procedures. With advancements in 3D printing technology, anatomically accurate and cost-effective physical models have emerged as a viable alternative for surgical training. This study aims to develop and validate a realistic 3D-printed lumbar spine model for non-cadaveric surgical education. The proposed model replicates the anatomical and biomechanical properties of the L1-S1 segment and is produced using fused deposition modeling (FDM) 3D printing technology with polylactic acid (PLA) vertebrae, PolyFlex TPU95 intervertebral discs, and an elastic TPU (thermoplastic polyurethane) rod to mimic physiological movement. The model is based on DICOM imaging data from a CT scan of a patient's spine, optimized for biomechanical resistance and realistic pedicle screw placement training. It was tested in hands-on neurosurgical workshops at St. Ivan Rilski University Hospital in Sofia. Post-training X-ray analysis confirmed the accuracy of screw positioning and the anatomical fidelity of the model. The results demonstrate that this 3D-printed lumbar spine model provides an accessible, customizable, and reliable training tool for spine surgery. Future improvements may include multi-material printing, augmented reality (AR) integration, and adaptations for pathological conditions.