Torque Control during Bone Insertion of Cortical Screws

A critical factor in the biomechan cal stability of orthopaedic surgery is tightening of cortical screws which currently are surgeon's skills based. This paper provides recommendation for better control and optimal insertion of cortical screws. Experiments on animal bones allowed determination of clamping torque limits for an efficient tight. Employment of digital torque screwdrivers allows direct determination of threshold torque. Than for any bone density and any type of screw the peak clamping torque is 1.75 threshold torque. The clamping torque limits are between 1.5 .... 2 threshold torque. This is calculated analytically and validated by experimental measurements. (C) 2020 The Authors. Published by Elsevier B.V.