Table 4 Measurements at all lumbar vertebral levels (n = 96)
From: Cortical screw placement with a spinous process clamp guide: a cadaver study accessing accuracy
Parameter | Groups | Total (n = 96) | L1 (n = 8) | L2 (n = 8) | L3 (n = 8) | L4 (n = 8) | L5 (n = 8) | S1 (n = 8) |
|---|---|---|---|---|---|---|---|---|
LA (°) | Planning screws (n = 48) | 9.2 ± 1.8 | 9.0 ± 0.8 | 9.9 ± 0.8 | 10.3 ± 0.8 | 11.2 ± 0.7 | 8.4 ± 0.8 | 6.2 ± 0.5 |
Inserted screws (n = 48) | 9.1 ± 1.7 | 8.6 ± 1.0 | 9.4 ± 0.8 | 10.1 ± 0.5 | 11.3 ± 0.8 | 8.6 ± 0.8 | 6.4 ± 0.5 | |
p value | 0.662 | 0.744 | 0.709 | 0.085 | 0.830 | 0.901 | 0.735 | |
t/Z/ × 2 | 0.377 | 0.982 | 1.237 | 0.663 | − 0.128 | − 0.445 | − 0.635 | |
CA (°) | Planning screws (n = 48) | 22.8 ± 5.6 | 27.7 ± 1.2 | 27.8 ± 3.5 | 24.1 ± 2.0 | 22.3 ± 3.7 | 20.5 ± 2.0 | 14.4 ± 4.6 |
Inserted screws (n = 48) | 23.0 ± 5.1 | 30.0 ± 1.0 | 27.3 ± 3.0 | 24.3 ± 2.0 | 21.2 ± 2.1 | 20.9 ± 2.5 | 15.3 ± 3.1 | |
p value | 0.760 | 0.388 | 0.393 | 0.766 | 0.155 | 0.734 | 0.146 | |
t/Z/ × 2 | − 0.213 | − 2.765 | 0.328 | − 0.203 | 0.708 | − 0.347 | − 0.478 | |
DBST (mm) | Planning screws (n = 48) | 38.5 ± 3.9 | 34.7 ± 2.9 | 35.4 ± 2.5 | 37.3 ± 1.6 | 38.2 ± 1.1 | 40.8 ± 0.9 | 44.8 ± 1.3 |
Inserted screws (n = 48) | 39.6 ± 4.3 | 35.5 ± 2.2 | 35.8 ± 1.7 | 37.5 ± 1.4 | 39.3 ± 2.2 | 43.7 ± 1.0 | 46.1 ± 1.3 | |
p value | 0.272 | 0.713 | 0.435 | 0.625 | 0.166 | 0.887 | 0.872 | |
t/Z/ × 2 | − 0.929 | − 0.438 | − 0.325 | − 0.211 | − 0.836 | − 4.330 | − 1.382 |