Differences in lower extremity compensatory mechanisms (SFA, KA, AA, PS, GSA) by age group.
| Compensatory Mechanism and Age Group, y | Pre- to Postoperative Change | P |
| TK | ||
| <40 | –1.8 | 0.410 |
| 40–65 | –0.79 | 0.502 |
| ≥65 | –2.0 | 0.676 |
| SFA | ||
| <40 | 5.5 | 0.075 |
| 40–65 | 6.5 | 0.275 |
| ≥65 | –2.3 | 0.088 |
| KA | ||
| <40 | –2.5 | 0.264 |
| 40–65 | 5.4 | 0.275 |
| ≥65 | –0.12 | 0.931 |
| AA | ||
| <40 | –0.44 | 0.757 |
| 40–65 | 1.14 | 0.002a |
| ≥65 | –0.74 | 0.241 |
| PS | ||
| <40 | –6.4 | 0.517 |
| 40–65 | –4.9 | 0.149 |
| ≥65 | 6.5 | 0.521 |
| GSA | ||
| <40 | –0.48 | 0.004a |
| 40–65 | –2.8 | 0.224 |
| ≥65 | 0.37 | 0.629 |
↵a Statistically significant.
AA, ankle angle; CD, cervical deformity; GSA, global sagittal angle; KA, knee angle; PS, pelvic shift; SFA, sacrofemoral angle; TK, thoracic kyphosis.