Patients’ demographics and surgery level.
| Category | N = 39 |
| Age, y, mean ± SD | 49.49 ± 9.36 |
| Sex, n | |
| Male | 33 |
| Female | 6 |
| Body mass index, kg/m2, mean ± SD | 26.80 ± 3.00 |
| Smoke, n | 20 |
| Diabetes mellitus, n | 5 |
| No. of segments artificial disc replacement operated, n (%) | |
| C3-C4 | 3 (7.7%) |
| C4-C5 | 13 (33.3%) |
| C5-C6 | 19 (48.7%) |
| C4-C5-C6 | 3 (7.7%) |
| C5-C6-C7 | 1 (2.6%) |
| No. of segments laminoplasty operated, n (%) | |
| C3-C4-C5-C6 | 26 (66.7%) |
| C4-C5-C6 | 12 (30.8%) |
| C3-C4-C5 | 1 (2.6%) |