[Assessment of sacroiliacal joint mobility in patients with low back pain].

Introduction: Sagittal alignment of the pelvis is typically characterized using three fundamental parameters. Among these, pelvic incidence is traditionally considered to be anatomically 'constant'.

Aim: We aimed to analyze the pelvic parameters of low back pain patients with suspected sacroiliac joint laxity.

Method: Pelvic parameters were assessed in standing and seated EOS 2D/3D radiographs of 48 cases of persistent low back pain, and compared to upper body position using cluster analysis and t-test.

Results: Median pelvic incidence did not differ statistically between standing and sitting (47.8°-47.7°). However, in individual analysis 7 cases (15%) exhibited a forward tilt in their upper body with an increased pelvic incidence, and 7 cases (15%) showed a backward upper body tilt. No change was found in 34 cases.

Conclusion: Our results indicate the pelvis should not be regarded as a rigid unit, as in some cases significant appreciable sacroiliac joint laxity can occur. Orv Hetil. 2017; 158(52): 2079-2085.