Open AccessCT-Based Navigation THA Using CT-Fluoro Matching Registration
Author(s) -
Kunihiko Tokunaga
Publication year - 2019
Publication title -
epic series in health sciences
Language(s) - English
Resource type - Conference proceedings
ISSN - 2398-5305
DOI - 10.29007/9vh1
Subject(s) - confidence interval , standard deviation , nuclear medicine , image registration , absolute deviation , medicine , computed tomography , orthodontics , mathematics , artificial intelligence , computer science , surgery , statistics , image (mathematics)
CT-fluoro matching (CFM) registration is one of the registrations for CT-based navigation developed by Brainlab company, in which the contours of the intraoperative fluoroscopic 2D X-ray images were matched to the contours of 3D pelvic and femoral models created based on the preoperative CT images. Brainlab company stopped to provide CT-based navigation and shifted to imageless navigation for THA. Therefore, clinical efficacy of this CFM registration is not well known. We analyzed the accuracy of implant position and postoperative complications after CT-based navigation assisted THA of 45 cases (43 females, 2 males, average age: 72.7 y.o.) using CFM registration and cementless implants (SQRUM cups and J-Taper high offset stems [Kyocera, Japan]). The differences (average ± standard deviation of absolute values, [95% confidence interval]) between the pre- and post- operative angles of cup inclination, anteversion, and stem antetorsion were 2.2 ± 1.50, [1.8~2.60], 3.7 ± 3.10, [2.9~4.60], 5.9 ± 4.50, [4.6~7.10], respectively. The differences (average ± standard deviation of absolute values, [95% confidence interval]) between the intra- and post-operative angles of cup inclination, anteversion, and stem antetorsion were 2.2 ± 1.70, [1.7~2.60], 2.3 ± 2.10, [1.7~2.80],4.6 ± 3.00, [3.7~5.40], respectively. These values were clinically acceptable when we compared with the previous accuracy studies of CT-based navigation using surface matching registration. There was no dislocation after THA in this study. From these results, CFM registration is useful for THA. However, this CT-based navigation with CFM registration will be discontinued in near future. Novel CT-based navigation systems should be developed based on this CFM registration procedure.