[Consistency comparison of the parameters of the lumbar spine-pelvic sagittal plane between the whole-spine EOS images system and traditional X-ray].

OBJECTIVE

To explore the consistency of the parameters of the lumbar spine pelvic sagittal plane between the whole spine EOS images (EOS) and traditional X-ray imaging.

METHODS

A total of 50 patients (26 males and 24 females) hospitalized in the Spine Surgery Department of Beijing Jishuitan Hospital from May to July 2019 were selected for standard standing EOS full-length spine anterolateral and traditional X-ray lumbar pelvic anterior and lateral X-rays. Two attending physicians used Surgimap software to measure the pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL) of the two types of images and repeated these process after two weeks. The consistency test (reliability analysis) was performed on the results measured by two physicians, and the results measured at the two time points were tested for intra-observer consistency (repeatability analysis).The data were combined to perform consistency and difference tests for the parameters between two types of images finally.

RESULTS

The mean values of PI measured by EOS imaging and traditional X-ray imaging were(50.5±12.6)° and (51.4±12.2)°, mean difference 0.9, 95% credible interval (0.2-1.6), P=0.020; the mean values of PT were (16.2±8.9)° and (16.9±8.6)°, mean difference 0.7, 95% credible interval (-0.6-2.0), P=0.283; the mean values of SS were (34.3±9.9)° and (34.5±10.4)°, mean difference 0.2, 95% credible interval (-1.2-1.5), P=0.800;the mean values of LL were (42.7±14.9)° and (43.3±15.3)°, mean difference 0.6, 95% confidence interval (-0.8-2.0), P=0.149. The difference in PI between the two imaging methods was statistically significant (P =0.020, P <0.05), but the average difference was small (0.9°), there was no clinical difference. There were no significant differences in PT, SS and LL between the two imaging methods (P>0.05). Inter-group reliability analysis showed excellent agreement between the two physicians in measuring lateral PI, PT, SS and LL using Surgimap software (correlation coefficients within EOS imaging were 0.984, 0.993, 0.980, 0.989;correlation coefficients within X-ray imaging were 0.975, 0.985, 0.976, 0.988). Repeatability analysis showed that PI, PT, SS and LL measured by the two attending physicians at two time points had excellent consistency(ICC within the group was 0.963-0.996).

CONCLUSION

In the local lumbar pelvis segment, the PI, PT SS and LL measured by EOS imaging and traditional X-ray imaging had good agreement, and there was no difference in guiding clinical application.