Segment

RA patients

Controls

Comparison (χ²-test)

L1-L2 Left

1 (3.0%)

1 (1.8%)

χ² = 0.157, d.f. = 1, p = 0.692

L1-L2 Right

0 (0.0%)

0 (0.0%)

-

L2-L3 Left

0 (0.0%)

1 (1.7%)

χ² = 0.575, d.f. = 1, p = 0.448

L2-L3 Right

1 (3.0%)

1 (1.8%)

χ² = 0.157, d.f. = 1, p = 0.692

L3-L4 Left

2 (6.1%)

2 (3.4%)

χ² = 0.363, d.f. = 1, p = 0.547

L3-L4 Right

1 (3.0%)

4 (6.9%)

χ² = 0.605, d.f. = 1, p = 0.436

L4-L5 Left

2 (6.1%)

2 (3.4%)

χ² = 0.342, d.f. = 1, p = 0.559

L4-L5 Right

4 (12.1%)

3 (5.3%)

χ² = 1.370, d.f. = 1, p = 0.242

L5-S1 Left

4 (12.1%)

5 (8.9%)

χ² = 0.233, d.f. = 1, p = 0.629

L5-S1 Right

0 (0.0%)

5 (8.8%)

χ² = 3.065, d.f. = 1, p = 0.080

Total L1-S1 score

9 (27.3%)

11 (19.0%)

χ² = 0.846, d.f. = 1, p = 0.358