Radiation-free drill guidance in interlocking of intramedullary nails

Abstract

Intramedullary nailing is a technically demanding procedure which involves an excessive amount of X-ray acquisitions; one study lists as many as 48 to successfully complete the procedure. In this work, a novel low cost radiation-free drilling guide is designed to assist surgeons in completing the distal locking procedure without any X-ray acquisitions. Using an augmented reality fluoroscope that coregisters optical and X-ray images, we exploit solely the optical images to detect the drilling guide in order to estimate the tip position in real-time in X-ray. We tested over 200 random drill guide poses showing a mean tip-estimation error of 1.72 ± 0.7 mm which is significantly robust and accurate for the interlocking. In a preclinical study on dry bone phantom, three expert surgeons successfully completed the interlocking 56 out of 60 trials with no X-ray acquisition for guidance and an average time of 2 min.