Correlation between cervical spine levels surgically treated, cervical alignment, and clinical/radiological outcome.
| Single Level, Mean (SD) | Multilevel, Mean (SD) | P a | |
| Postoperative Clinical Status | |||
| NDI | 25.4 (13.9) | 29.7 (19.2) | 0.25 |
| Cervical VAS | 4.1 (2.3) | 4.4 (2.7) | 0.5 |
| Radicular VAS | 3.9 (2.2) | 3.9 (2.6) | 0.9 |
| JOA | 16.9 (1.2) | 17 (1.5) | 0.8 |
| Last Evaluation Clinical Status | |||
| NDI | 27.5 (15) | 31.4 (19.8) | 0.3 |
| Cervical VAS | 4.3 (2.4) | 4.8 (2.9) | 0.4 |
| Radicular VAS | 4.2 (2.7) | 4.4 (2.8) | 0.7 |
| JOA | 17 (1.2) | 16.8 (1.5) | 0.6 |
| Postoperative Cervical Angles | |||
| C2-C7 Cobb’s angle | −13 (15.5) | −16 (10.8) | 0.2 |
| T1 slope | 27.7 (13.3) | 27.8 (9.5) | 0.9 |
| C0-C2 angle | 18.8 (12.6) | 18.7 (10.8) | 0.9 |
| Cervical segmental Cobb angle | −5.1 (7.1) | −9.2 (9.4) | 0.02 |
| Harrison cervical angle | 17.6 (11.4) | 17.8 (9.7) | 0.9 |
| Cervical sagittal vertical axis | 25.4 (9.9) | 23 (9.9) | 0.2 |
Abbreviations: JOA, Japanese Orthopedic Association; NDI, Neck Disability Index; VAS, visual analog scale.
↵a t test for independent samples.