A cost-effective navigation system for peri-acetabular osteotomy surgery

Abstract

Purpose. To develop and evaluate a low-cost, surgical navigation solution for periacetabular osteotomy (PAO) surgery. Methods. A commercially available low-cost miniature computer is used together with a camera board (Raspberry Pi 2 Model B, Camera Module PiNoir) to track planar markers (Aruco markers). The overall setup of the tracking unit is small enough to be attached directly to the patient’s pelvis. The patient’s pelvis is registered by estimating the pose of a planar marker which is attached to an anterior pelvic plane (APP) digitization device. Next, one marker is attached to the acetabular fragment and the initial orientation of the fragment is recorded. The estimated orientation of the fragment is transmitted to the host computer for visualization. Results. A plastic bone study (eight hip joints) was performed to validate the proposed system. The comparison with a previously developed optical tracking-based system showed no statistical significant difference between measurements obtained from the two systems. In all eight hip joints the mean absolute difference was below 2 ◦ for both anteversion and inclination and a very strong correlation was observed. Conclusions. We show that with our proof-of-principle system, we are able to compute the acetabular orientation accurately.