Int Orthop. 2026 Jun 22. doi: 10.1007/s00264-026-06921-0. Online ahead of print.
ABSTRACT
PURPOSE: Accurate acetabular cup placement is essential in total hip arthroplasty (THA). We hypothesized that the newly introduced Computed Tomography (CT)-based portable navigation system would demonstrate accuracy comparable to that of the imageless portable navigation system. The aim of this study was to compare cup placement accuracy between the CT-based and imageless portable navigation systems of the same platform in THA performed in the lateral decubitus position.
METHODS: This retrospective cross-sectional study included 36 patients who underwent primary THA via a direct lateral approach in the lateral decubitus position. In all cases, both imageless and CT-based portable navigation systems were used concurrently. Postoperative cup alignment was evaluated using three-dimensional CT (3D-CT). The primary outcome was the absolute error in cup inclination and anteversion, defined as the difference between intraoperative navigation values and postoperative 3D-CT measurements in the functional. Secondary outcomes included outlier rates and registration success rates.
RESULTS: No statistically significant differences were observed between the imageless and CT-based portable navigation systems in the mean absolute error for inclination (2.2 ± 1.8° vs. 2.3 ± 1.8°, p = 0.93) or anteversion (2.3 ± 2.3° vs. 2.6 ± 2.5°, p = 0.41). There were no significant differences in outlier proportions. The registration success rate was 92% (36/39) due to three technical failures.
CONCLUSION: In this preliminary study, the CT-based portable navigation system demonstrated cup placement accuracy comparable to that of the imageless portable navigation system. Although the CT-based system may provide additional spatial information intraoperatively, its impact on clinical outcomes remains unclear and requires further longitudinal investigation.
PMID:42332259 | DOI:10.1007/s00264-026-06921-0
