Fiducial-Free 2D/3D Registration for Robot-Assisted Femoroplasty

Gao C, Farvardin A, Grupp R, Bakhtiarinejad M, Ma L, Thies M, Unberath M, Taylor R, Armand M (2020)

Publication Language: English

Publication Type: Journal article

Publication year: 2020


Book Volume: 2

Pages Range: 437-446

Journal Issue: 3

DOI: 10.1109/TMRB.2020.3012460


Femoroplasty is a proposed alternative therapeutic method for preventing osteoporotic hip fractures in the elderly. Previously developed navigation system for femoroplasty required the attachment of an external X-ray fiducial to the femur. We propose a fiducial-free 2D/3D registration pipeline using fluoroscopic images for robot-assisted femoroplasty. Intraoperative fluoroscopic images are taken from multiple views to perform registration of the femur and drilling/injection device. The proposed method was tested through comprehensive simulation and cadaveric studies. Performance was evaluated on the registration error of the femur and the drilling/injection device. In simulations, the proposed approach achieved a mean accuracy of 1.26±0.74 mm for the relative planned injection entry point; 0.63 ± 0.21◦ and 0.17 ± 0.19◦ for the femur injection path direction and device guide direction, respectively. In the cadaver studies, a mean error of 2.64±1.10 mm was achieved between the planned entry point and the device guide tip. The biomechanical analysis showed that even with a 4 mm translational deviation from the optimal injection path, the yield load prior to fracture increased by 40.7%. This result suggests that the fiducial-less 2D/3D registration is sufficiently accurate to guide robot assisted femoroplasty.

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Gao, C., Farvardin, A., Grupp, R., Bakhtiarinejad, M., Ma, L., Thies, M.,... Armand, M. (2020). Fiducial-Free 2D/3D Registration for Robot-Assisted Femoroplasty. IEEE Transactions on Medical Robotics and Bionics, 2(3), 437-446.


Gao, Cong, et al. "Fiducial-Free 2D/3D Registration for Robot-Assisted Femoroplasty." IEEE Transactions on Medical Robotics and Bionics 2.3 (2020): 437-446.

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