Implant Deformation on Digital Preoperative Planning of Lower Extremities Fractures

摘要

Preoperative planning is an essential step before performing any surgical procedure. Computer Aided Orthopedic Surgery (CAOS) systems are extensively used for the planning of surgeries for fractures of lower extremities. These systems are input an X-Ray image of the fracture and the planning can be digitally over-laid onto the image. In many cases, when an implant is added to the planning, it does not fit perfectly in the patient's anatomy and therefore it is bended to be adjusted to the bone. This paper presents a new method for the deformation of implants in CAOS systems, based on the Moving Least Squares (MLS) method. Several improvements over the original MLS are introduced to achieve results visually similar to the real procedure and make the deformation process easier and simpler for the surgeon. Over 100 clinical surgeries have been already planned successfully using a CAOS system that employs the proposed technique.