Angulation difference based on distance from reference frame.
| Level from reference frame | No. of screws | Axial | Sagittal | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean virtual angle (°) | Mean actual angle (°) | Mean angle difference (°) | Percent error | Mean virtual angle (°) | Mean actual angle (°) | Mean angle difference (°) | Percent error | ||
| 0 | 45 | 14.1 | 14.3 | 1.83 | 0.9% | 3.0 | 3.6 | 2.02 | 1.1% |
| 1 | 64 | 16.5 | 16.6 | 1.50 | 0.8% | 3.8 | 3.2 | 1.50 | 1.4% |
| 2 | 37 | 15.5 | 14.6 | 2.22 | 1.1% | 3.4 | 3.6 | 2.22 | 0.9% |
| 3 | 34 | 19.2 | 18.1 | 2.44 | 1.2% | 4.5 | 4.0 | 2.44 | 0.9% |
| 4 | 23 | 14.1 | 13.3 | 2.13 | 1.1% | 3.7 | 3.1 | 2.13 | 1.3% |
| 5 | 19 | 18.4 | 17.3 | 2.68 | 1.3% | 2.2 | 1.4 | 2.68 | 1.3% |
| 6 | 9 | 36.2 | 35.4 | 2.56 | 1.3% | 5.4 | 5.7 | 2.56 | 1.2% |
| 7-10 | 9 | 19.0 | 15.0 | 6.00 | 3.0% | 5.4 | 5.6 | 6.00 | 1.1% |