Patient demographics
| Group 1 | Group 2 | Group 3 | |
|---|---|---|---|
| No. of patients (female %) | 328 (70%) | 226 (64%) | 101 (66%) |
| Mean age by year (SD) | 75 (11) | 74 (12) | 73 (11) |
| Median % of available patients in different follow-up time points (range) | 68% (22%–93%) | 70% (32%–92%) | 70% (26%–93%) |
| No. of levels | 328 | 539 | 328 |
| Upper thoracic (T1–T4) | 1 (0.5%) | 8 (1%) | 7 (2%) |
| Mid thoracic (T5–T8) | 64 (19.5%) | 85 (16%) | 55 (17%) |
| Lower thoracic (T9–T12) | 100 (30.5%) | 171 (32%) | 112 (34%) |
| Upper lumbar (L1–L3) | 125 (38%) | 199 (37%) | 115 (35%) |
| Lower lumbar (L4–L5) | 35 (10.5%) | 76 (14%) | 38 (11.5%) |
| Sacrolplasty | 3 (1%) | 0 | 1 (0.5%) |