Table 3.
Pedicle screw diameter and length
| Variable | RAF | FGF | Statistic (χ2) | P value |
|---|---|---|---|---|
| No. of screws | ||||
| Total | 136 | 144 | 5.309 | 0.379 |
| T10 | 2 | 6 | ||
| T11 | 22 | 20 | ||
| T12 | 36 | 34 | ||
| L1 | 32 | 38 | ||
| L2 | 34 | 28 | ||
| L3 | 10 | 18 | ||
| Mean screw diameter (range), mm | ||||
| Total | 6.04 (5.0–7.0) | 5.78 (5.0–6.5) | − 3.067 | 0.000** |
| T10 | 5.5 (5.5) | 5.17 (5.0–5.5) | – | – |
| T11 | 6.09 (5.5–7.0) | 5.90 (5.5–6.5) | -0.975 | 0.330 |
| T12 | 6.11 (5.5–7.0) | 6.04 (5.5–6.5) | -0.332 | 0.740 |
| L1 | 5.81 (5.0–6.5) | 5.29 (5.0–6.0) | -4.281 | 0.000** |
| L2 | 6.12 (5.5–7.0) | 6.07 (5.5–6.5) | -0.238 | 0.812 |
| L3 | 6.20 (6.0–6.5) | 5.94 (5.5–6.5) | -2.143 | 0.032* |
| Mean screw length (range), mm | ||||
| Total | 50.45 (40–55) | 48.63 (40–55) | -3.561 | 0.000** |
| T10 | 50 (50) | 48.54 (45–50) | – | – |
| T11 | 50.00 (40–55) | 49.50 (40–55) | − 0.320 | 0.749 |
| T12 | 49.19 (45–55) | 47.35 (45–55) | 2.064 | 0.039* |
| L1 | 50.65 (40–55) | 48.96 (40–55) | − 1.966 | 0.049* |
| L2 | 51.18 (45–55) | 49.34 (45–55) | − 1.391 | 0.164 |
| L3 | 53.00 (50–55) | 48.33 (45–55) | − 3.144 | 0.020* |
RAF robot-assisted percutaneous pedicle screw fixation, FGF fluoroscopy-guided percutaneous pedicle screw fixation
*P < 0.05; **P < 0.01, statistically significant