Effectiveness Evaluation of Penetration-Detection Scheme for Surgical Drill Using Thrust Force and Positional Information

The risk of spinal cord injury when cutting into the spine is a particular concern in orthopedic surgery. Surgeons must rely entirely on their haptic senses to determine bone penetration. Therefore, surgeons incur heavy burdens. Some studies have introduced penetration-detection systems using torque information. However, these method requires obtaining the characteristics of the bone before the actual cutting. Our previous study introduced an orthopedic haptic drill equipped with a penetration-detection system. This drill detects penetration by monitoring changes in the force of a linear motor. In this study, the advantage of using force over torque for penetration detection was verified through theoretical modeling and experiments. The theoretical model indicates that the thrust force reacts more sensitively than the torque at penetration. The detection methods using the force-based and torque-based methods were compared through experiments. The experimental results verified that the force-based detection method has advantages in terms of detection accuracy and detection time. The results demonstrated the efficacy of the proposed method, highlighting its potential utility in improving the accuracy and safety of orthopedic procedures.