Table 2.
Comparison of postoperative alignment
| 3D preoperative planning group (n = 104) |
Robotics group (n = 52) |
P value | |
|---|---|---|---|
| HKA | 179.3° ± 2.5° | 181.1° ± 1.6° | < 0.001a |
| FFC | 90.3° ± 1.9° | 89.5° ± 1.5° | 0.007a |
| FTC | 89.5° ± 2.1° | 90.0° ± 1.3° | 0.077a |
| LFC | 88.2° ± 2.5° | 88.5° ± 2.3° | 0.577a |
| LTC | 86.0° ± 2.7° | 86.7° ± 2.3° | 0.100a |
| HKA absolute deviation | 2.0° ± 1.7° | 1.7° ± 1.0° | 0.150a |
| FFC absolute deviation | 1.6° ± 1.0° | 1.3° ± 0.9° | 0.039a |
| FTC absolute deviation | 1.7° ± 1.3° | 1.0° ± 0.7° | < 0.001a |
| LFC absolute deviation | 2.6° ± 1.7° | 2.3° ± 1.6° | 0.332a |
| LTC absolute deviation | 2.2° ± 1.8° | 1.9° ± 1.3° | 0.163a |
| HKA outlier (n, %) | 16, 15.4% | 1, 1.9% | 0.011b |
| FFC outlier (n, %) | 13, 12.5% | 1, 1.9% | 0.060b |
| FTC outlier (n, %) | 14, 13.5% | 0, 0% | 0.013b |
| LFC outlier (n, %) | 30, 28.8% | 7, 13.5% | 0.033b |
| LTC outlier (n, %) | 28, 26.9% | 2, 3.8% | 0.001b |
HKA, hip–knee–ankle angle; FFC, frontal femoral component angle; FTC, frontal tibial component angle; LFC, lateral femoral component angle; and LTC, lateral tibial component angle. Values exceeding the target value by 3 degrees were recorded as outliers
aStands for t test, and bStands for χ2 test. P value in bold indicates statistical significance