Patient characteristics (categorical variables).
| Variable | n | % |
| Gender | ||
| Men | 209 | 34.3 |
| Women | 401 | 65.7 |
| Comorbidity | ||
| None | 374 | 61.3 |
| HTN | 82 | 13.4 |
| HTN and diabetes | 50 | 8.2 |
| Arthritis | 9 | 1.5 |
| Others | 95 | 15.6 |
| Procedure site | ||
| Left | 228 | 37.4 |
| Right | 294 | 48.2 |
| Central | 75 | 12.3 |
| Bilateral | 13 | 2.1 |
| No. of Levels | ||
| 1 | 536 | 87.8 |
| 2 | 63 | 10.3 |
| 3 and above | 11 | 1.9 |
| Smoking | ||
| Yes | 83 | 10.3 |
| No | 547 | 88.7 |
| Alcohol | ||
| Yes | 104 | 17 |
| No | 506 | 83 |
| Low Back Pain | ||
| Yes | 610 | 100 |
| No | 0 | 0 |
| Leg Pain | ||
| Yes | 536 | 87.9 |
| No | 74 | 12.1 |
| Neurological Symptoms Before Procedure | ||
| In motion | 453 | 74.3 |
| Numbness and tingling | 157 | 25.7 |
| Complications | ||
| None | 602 | 98.7 |
| Yes | 8 | 1.3 |
Abbreviation: HTN, hypertension.