Patient baseline characteristics.
| Characteristic | % Total (n = 811) |
| Age (mean ± SD) | 44.6 ± 13.6 |
| Gender % (n) | |
| Female | 29.9% (243) |
| Male | 70.1% (568) |
| BMI | |
| <30 kg/m2 | 60.4% (483) |
| ≥30 kg/m2 | 39.6% (317) |
| Smoking Status | |
| Nonsmoker | 83.2% (675) |
| Smoker | 16.8% (136) |
| Diabetes | |
| Diabetic | 5.8% (47) |
| Nondiabetic | 94.2% (764) |
| ASA score | |
| <2 | 34.5% (232) |
| ≥2 | 65.5% (440) |
| Ageless CCI | |
| <1 | 58.8% (440) |
| ≥1 | 41.2% (308) |
| Insurance | |
| Non-WC | 69.4% (563) |
| WC | 30.6% (245) |
| Operative length (min) | 45.7 ± 15.0 |
| EBL (mean ± SD; mL) | 31.4 ± 14.2 |
| LOS (mean ± SD; h) | 5.7 ± 6.6 |
| Operative technique | |
| Laminectomy | 17.9% (144) |
| Discectomy | 11.5% (92) |
| Laminectomy + discectomy | 70.6% (567) |
| Number of operative levels | |
| Single | 81.7% (663) |
| Multilevel | 18.3% (148) |
| Spinal pathology | |
| HNP | 77.1% (625) |
| Central stenosis | 61.2% (496) |
| Foraminal stenosis | 33.9% (275) |
ASA, American Society of Anesthesiologists; BMI, body mass index; CCI, Charlson Comorbidity Index; EBL, estimated blood loss; HNP, herniated nucleus pulposus; LOS, length of stay; WC, workers’ compensation.