Development of Screwdriver for Maxillofacial Miniplate Implant with Torque-limiting Capability

摘要

Screwdriver was used extensively in medical field especially during surgery activities. The use of screwdriver is to plant or remove implant plate by tightening or loosening screw on implant plate. The process of tightening screw on implant plate plays an important role due to risk of bone and screw fracture. Optimum torque is a crucial parameter in order to reduce the risk of loosening screw. On the other hand, excessive generated torque may cause bone or screw fracture. Therefore limiting the torque generated by clinicians is important to reduce risk of implantation. The hand screwdriver with torque limiter is one of the solutions for this problem. The work mechanism of this tool is when the screw is already tight the torque generated would not force the screw to rotate further, but would be transferred to the spring and gear and make the ball moves up and down repeatedly. Work/motion simulation is conducted to ensure the screwdriver is able to work as its function. To get the most ergonomics design of this screwdriver, five designs of screwdriver handler and grip were assessed by clinicians. Screwdriver with design A is subjectively the most ergonomics design among the clinicians.