Fabrication of a 3D-Printed Fixation Device and Quantitative Analysis of Reproducibility in Hip Joint Axiolateral Radiography

This study aimed to evaluate the utility of a 3D-printed, weight-bearing auxiliary device designed to improve reproducibility and facilitate detector fixation during axiolateral radiography of hip joints known to be affected by inter-operator variability. The experiment was conducted using a radiolucent human phantom. Multiple radiographs were taken under identical conditions. Reproducibility and utility were assessed by measuring the α angle and off-set ratio from acquired images. Results showed that the mean α angle was 51.58° (±5.14°) with the auxiliary device and 50.45° (±4.90°) without it, with no statistically significant difference between conditions (Wilcoxon signed-rank test, p = 0.2024), indicating no measurable improvement in reproducibility. The off-set ratio likewise did not differ significantly between conditions (p = 0.1704). However, using the device did not significantly affect the off-set ratio. In conclusion, the auxiliary device developed in this study allows for consistent detector angle maintenance and fixation during hip joint axiolateral projection, thereby improving reproducibility and ease of examination. This suggests its potential usefulness for achieving more accurate imaging in clinical settings.