Table 1.
Baseline characteristics before and after 1:2 matching
| Characteristics | Before PSM (n = 248) |
After PSM (n = 156) |
||||
|---|---|---|---|---|---|---|
| 3D preoperative planning group (n = 196) |
Robotics group (n = 52) |
P value | 3D preoperative planning group (n = 104) |
Robotics group (n = 52) |
P value | |
| Gender (male/female) | 52:144 | 11:41 | 0.428b | 23:81 | 11:41 | 0.891b |
| Side (left/right) | 95:101 | 31:21 | 0.153b | 61:43 | 31:21 | 0.908b |
| Age (years) | 69.3 ± 8.4 | 66.1 ± 7.9 | 0.016a | 66.9 ± 9.4 | 66.1 ± 7.9 | 0.585a |
| BMI (kg/m2) | 25.6 ± 3.2 | 26.0 ± 4.2 | 0.472a | 26.0 ± 3.5 | 26.0 ± 4.2 | 0.988a |
| Pre-HKA (°) | 170.6 ± 8.8 | 172.4 ± 6.4 | 0.110a | 172.1 ± 9.1 | 172.4 ± 6.4 | 0.857a |
PSM, propensity score matching; BMI, body mass index; and HKA, hip–knee–ankle angle
aStands for t test, and bStands for χ2 test. P value in bold indicates statistical significance