Automatic Bone Drilling in Orthopedic Surgery - Overcoming of the Drill Bit Bending at the Second Cortex

Abstract

This paper discusses a problem appeared by drill bit bending during bone drilling in the orthopedic surgery, where precision is needed for screws to be implanted. The bone surface has a specific shape and the drill bit may slip a little along the bone before the process start, when a large thrust force is applied by hand-drilling. That could be seen and correct by the surgeon. But he can’t see inside – where the second cortex drilling starts. The drill bit bending leads to the worse screw fixation and even to the bone damage – if the drill bit stays off broken inside. To solve this problem an active force control is made by robot application. Experiments and results are presented.