Table 2.
Bilateral S2AI screw trajectory parameters on CT imaging
| Parameters | Left | Right | ||||
|---|---|---|---|---|---|---|
| AS deformity | AS non-deformity | non-AS deformity | AS deformity | AS non-deformity | non-AS deformity | |
| Sag angle (°) | 8.2 ± 11.7 | 26.6 ± 6.2* | 26.9 ± 10.2* | 8.0 ± 13.3 | 27.6 ± 6.9* | 27.0 ± 10.5* |
| Tsv angle (°) | 42.6 ± 6.7 | 43.1 ± 6.1 | 36.8 ± 7.3* | 43.1 ± 7.7 | 42.5 ± 6.3 | 36.9 ± 7.5* |
| Max-length (mm) | 111.6 ± 13.8 | 111.8 ± 11.3 | 114.4 ± 7.5 | 112.3 ± 14.7 | 112.9 ± 9.7 | 114.1 ± 7.8 |
| Sacral distance (mm) | 36.4 ± 6.1 | 34.9 ± 7.6 | 30.6 ± 6.6* | 38.7 ± 5.8 | 38.2 ± 4.8 | 30.6 ± 5.8* |
| Iliac width (mm) | 14.4 ± 4.0 | 12.3 ± 4.0 | 13.4 ± 2.0 | 14.3 ± 4.2 | 12.0 ± 1.9 | 13.6 ± 1.7 |
| S2 midline (mm) | 26.3 ± 3.6 | 25.4 ± 4.1 | 25.8 ± 6.4 | 26.4 ± 4.1 | 25.4 ± 2.6 | 25.7 ± 6.3 |
| Skin distance (mm) | 41.4 ± 14.8 | 36.8 ± 8.1 | 37.6 ± 9.9 | 41.0 ± 14.1 | 37.8 ± 5.7 | 37.2 ± 9.4 |
| Iliac wing (mm) | 12.7 ± 3.8 | 13.4 ± 4.1 | 12.5 ± 2.4 | 13.0 ± 4.5 | 13.2 ± 2.6 | 12.9 ± 2.0 |
| PSIS distance (mm) | 20.6 ± 12.3 | 20.1 ± 6.4 | 21.9 ± 9.1 | 20.1 ± 12.6 | 21.0 ± 6.3 | 21.3 ± 8.5 |
PSIS Posterior superior iliac spine
* data was statistically different from that of AS deformity (P < 0.05)