ARTHROBOT - A Robotic Hip Surgery System Using an Intra-Medulla Gauge : Experimental Results with Cadaver and Pig Bones

摘要

This paper presents a bone-mountable surgical robot system for Total Hip Arthroplasty (THA) using gauge-based registration, which is simpler than other robotic systems and shows comparable results to them. This gauge-guided robotic system replaces only the broaching procedure at which it is regarded that the most errors of a manual surgery are occurred, This gauge-based registration method drastically reduces the processes in preoperative planning by eliminating the need of CT scanning or other image processing methods, compared to other robotic systems that are used for hip surgery. Also this surgical system reduces damages to the femur because only the metaphyseal region of the femoral canal needs to be machined while leaving the diaphyseal hard bone untouched. Experiments were performed on 18 composite bones, 12 pig bones and 6 human cadaver bones. In the group of model bones and pig femurs, we evaluated the deviation of the orientation of a machined cavity with respect to the intended orientation. From cadaver bone group, we evaluated the differences between the orientation of an inserted stem and the value which is determined from anatomical features of a femur. From these experimental results, we could know that the developed system has sufficient machining accuracy and precision for clinical application.