Design of Medium Contact 3D Printed Guides in Robot-Assisted Laminectomy: Finite Element Analysis and Animal Experiment

The accuracy of 3D-printed guides alignment during robot-assisted spinal surgery is significantly influenced by the size of the contact area for registration. An undersized contact area may result in unstable registration, whereas an oversized contact area can increase the dissection area of soft tissues. This paper introduces a novel medium contact (MC) guide design procedure based on a four-point alignment method, which is specifically tailored for posterior laminectomy procedures. A comparative finite element analysis against the widely utilized full contact (FC) guides demonstrated that the MC guide, which occupies only 36.28% of the area of the FC guide, shows lower stress concentration and displacement when subjected to external forces according to the ABAQUS simulation environment. To verify the clinical efficacy of the MC guide, an in vivo animal experiment was conducted. The MC guide, post-printing, was employed for alignment, and successfully complete the registration of a robot-assisted spinal decompression surgery. The MC guide proposed herein not only ensures registration stability but also minimizes patient injury and surgeon's workload, and offers considerable reference value in clinical applications.