Analysis of Bone Cutting Mechanics in Orthopedic Surgery

Abstract

Bone cutting has been widely used in orthopedic surgery for repairing bone fractures and attaching implantable prosthetics. Temperature rise in the cutting process can cause necrosis when it is beyond a threshold value, depending on the species and age of the bone. Excessive cutting force may induce bone micro-fractures which lead to breakdown at the repair site. This thesis investigates the effect of cutting parameters on temperature and force in cutting of bovine and equine cannon bones. Vibration assisted drilling which enables intermittent contact between the cutting tool and the bone is conducted, and the effect of vibration assistance on the cutting performance is evaluated. Damages caused at the drill site of the bone are characterized by Micro-CT. Bone milling is used to shave the end of the bone to fit the plane of the artificial joint precisely. In this study, Taguchi method is used to evaluate the influence of the parameters such as spindle speed, feed rate and depth of cut on the milling process. This thesis provides insights in the mechanics of bone cutting process used in orthopedic surgery. The results provide optimum cutting operations to minimize the process induced bone damage.