Baseline characteristics.
| Characteristic | Maintained (n = 177) | Restored (n = 101) | Kyphotic (n = 30) | P Valuea,b |
| Age | 57.0 (59.5, 65.0) | 57.0 (49.0, 63.0) | 52.5 (45.5, 68.7) | 0.18 |
| Sex | 0.02 | |||
| Female | 86 (48.6%) | 39 (38.6%) | 20 (66.7%) | |
| Male | 91 (51.4%) | 62 (61.4%) | 10 (33.3%) | |
| Body mass index | 28.7 (25.6, 32.6) | 29.5 (27.1, 34.7) | 27.7 (24.9, 31.4) | 0.07 |
| Smoking status | 0.59 | |||
| Never smoker | 117 (66.1%) | 64 (63.4%) | 23 (76.7%) | |
| Former smoker | 39 (22.0%) | 27 (26.7%) | 6 (20.0%) | |
| Current smoker | 21 (11.9%) | 10 (9.9%) | 1 (3.3%) | |
| Charlson Comorbidity Index | 2.0 (1.0, 3.0) | 2.0 (1.0, 3.0) | 1.0 (0.7, 2.0) | 0.17 |
| Preoperative diagnosis | 0.52 | |||
| Radiculopathy | 90 (50.8%) | 49 (48.5%) | 19 (63.4%) | |
| Myelopathy | 73 (41.2%) | 46 (45.5%) | 10 (33.3%) | |
| Myeloradiculopathy | 14 (7.9%) | 6 (5.9%) | 1 (3.3%) | |
| Levels fused | 0.28 | |||
| 1 | 58 (32.8%) | 35 (34.7%) | 8 (26.7%) | |
| 2 | 58 (32.8%) | 42 (41.6%) | 10 (33.3%) | |
| 3 | 61 (34.5%) | 24 (23.8%) | 12 (40.0%) | |
| Preoperative C2-C7 Cobb angle | 8.9 (7.5, 9.7) | −5.6 (−6.5, −4.8) | −7.2 (−9.0, −5.4) | <0.001 |
| Postoperative C2-C7 Cobb angle | 12.3 (13.3, 11.2) | 8.2 (4.6, 13.8) | −6.2 (−8.5, −5.2) | <0.001 |
| Follow-up | 14.6 (12.1, 18.3) | 14.8 (12.6, 19.5) | 16.2 (12.0, 21.1) | 0.28 |