Table 1.
Deviations from preoperative mechanical leg axis in subtrochanteric osteotomies
| Angulation Error of the Osteotomy Plane | Plane | Error in the Mechanical Leg Axis Alignment per Rotation | ||||
|---|---|---|---|---|---|---|
| 5° | 10° | 15° | 20° | 30° | ||
| +/− 5° | Sagittal | 0.2° ± 0.2° | 0.3° ± 0.3° | 0.4° ± 0.3° | 0.5° ± 0.4° | 0.7° ± 0.5° |
| Frontal | 0.1° ± 0.1° | 0.2° ± 0.1° | 0.2° ± 0.1° | 0.3° ± 0.2° | 0.4° ± 0.2° | |
| +/− 10° | Sagittal | 0.2° ± 0.1° | 0.5° ± 0.2° | 0.7° ± 0.3° | 0.9° ± 0.3° | 1.4° ± 0.4° |
| Frontal | 0.1° ± 0.0° | 0.2° ± 0.1° | 0.3° ± 0.1° | 0.3° ± 0.1° | 0.4° ± 0.3° | |
| +/− 15° | Sagittal | 0.3° ± 0.1° | 0.7° ± 0.2° | 1.0° ± 0.3° | 1.4° ± 0.3° | 2.1° ± 0.4° |
| Frontal | 0.1° ± 0.0° | 0.2° ± 0.1° | 0.3° ± 0.1° | 0.4° ± 0.1° | 0.5° ± 0.3° | |
| +/− 20° | Sagittal | 0.5° ± 0.1° | 0.9° ± 0.2° | 1.4° ± 0.3° | 1.8° ± 0.3° | 2.8° ± 0.4° |
| Frontal | 0.2° ± 0.0° | 0.3° ± 0.1° | 0.4° ± 0.0° | 0.5° ± 0.0° | 0.5° ± 0.2° | |
| +/− 30° | Sagittal | 0.7° ± 0.1° | 1.3° ± 0.2° | 2.0° ± 0.2° | 2.7° ± 0.3° | 4.0° ± 0.4° |
| Frontal | 0.2° ± 0.1° | 0.3° ± 0.1° | 0.5° ± 0.1° | 0.6° ± 0.1° | 0.6° ± 0.2° | |
Errors in mechanical leg axis greater than 2° (mean value plus standard deviation) have been marked bold