Table 3: Comparison of radiographic measurements in patients with S1 involvement.

Characteristic Screw loosening value
YesNo

Number of patients10 (28.8%)36 (71.2%)
PI40.8 ± 12.141.6 ± 9.90.84
LL
 Pre-op29.9 ± 12.226.6 ± 9.90.45
 Post-op30.3 ± 11.935.9 ± 11.30.20
 Delta (post-op minus pre-op)0.4 ± 12.59.3 ± 12.80.07
PI − LL10.9 ± 13.215.0 ± 12.10.39

Values are presented by mean ± SD.
PI = pelvic incidence; LL = lumbar lordosis.