Customizable Cutting Template for Computer Assisted Osteotomies

Surgical interventions which require osteotomies are often performed with patient specific cutting templates based on CT images and modelled to fit patient's bones. Designing, manufacturing and shipping of these ad-hoc devices can require up to few weeks and high costs. In this work, we report a new idea for a customizable cutting template (CCT), adjustable to fit the patient's anatomy by means of registers. The length of these registers is calculated in a surgical planning software and, using at least three registers, it is possible to lean them on the bone blocking three DOF (degrees of freedom) of the pose of the template. Since the customizable template rests but does not interlock the bone, a verification system of the position is required, such as the AR (augmented reality) solution selected in this application. The proposed template was tested on a patient specific phantom of a pelvis surgical case, to compare its accuracy with the one obtained with a traditional patient specific guide. The positive results suggested this new method should be further investigated to apprehend if it is a valid alternative and its best applications.