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Updated: Jun 17, 2026
Augmented Reality Navigation-Guided Core Decompression for Osteonecrosis of Femoral Head
Published on: April 12, 2022
Comparison of augmented reality computed tomography-based and portable computed tomography-based navigation systems
Gai Kobayashi1, Yohei Naito1, Shine Tone1
1Department of Orthopaedic Surgery, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie, 514-8507, Japan.
Background:
This study aimed to compare the accuracy of acetabular cup placement in total hip arthroplasty (THA) using a computed tomography (CT)-based augmented reality (AR) navigation system and a CT-based portable navigation system, both employed simultaneously during surgery.
Methods:
Ninety hips in 88 patients who underwent primary cementless THA in the supine position between August 2023 and October 2024 were included. Both an AR CT-based navigation system and a portable CT-based navigation system were used concurrently. The cohort included 16 men and 72 women, with a mean age of 69 years and body mass index of 25 kg/m2. Target cup angles were 40° for radiographic inclination (RI) and 15° for radiographic anteversion (RA). Navigation error was defined as the absolute difference between intraoperative navigation values and postoperative CT measurements. These errors were compared between groups, and in the portable CT-based navigation system, between successful and failed registration cases.
Results:
RI navigation errors were similar between groups (2.4° ± 1.9° in the AR group vs. 2.7° ± 2.3° in the portable group). However, RA navigation error was significantly greater in the portable group (4.7° ± 3.7°) compared with the AR group (2.3° ± 2.1°). In the portable CT-based navigation system, successful registration was achieved in 35 of 77 hips (45.5%), whereas 42 hips (54.5%) showed failed registration. RA navigation error was significantly smaller in successful cases (3.7° ± 3.7°) than in failed cases (5.5° ± 3.8°). In an additional analysis, RA navigation error did not differ significantly between the corresponding AR group and the registration-success subgroup of the portable CT-based navigation system (2.7° ± 2.2° vs. 3.7° ± 3.7°).
Conclusion:
In supine THA, both navigation systems demonstrated good accuracy in RI. RA accuracy was worse in the portable CT-based system largely due to frequent registration failure but acceptable when registration succeeds.
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