Mean demographic values by surgical cohort.
| Demographics | Open Laminectomy and Fusion (n = 55) | Lateral Lumbar Interbody Fusion (n = 26) | Microdiscectomy (n = 9) | Endoscopic Decompression (n = 17) | P |
| Follow-up, mo, mean | 20.7 | 25.6 | 22.5 | 19.7 | 0.8 |
| Age, y, mean | 66.2 | 66.9 | 73.1 | 72.0 | 0.09 |
| Body mass index, mean | 28.4 | 27.8 | 28.9 | 26.0 | 0.229 |
| Smoker, n | 17 | 12 | 4 | 6 | 0.726 |
| Gender, % woman | 54.7 | 53.8 | 33.3 | 35.3 | 0.378 |
| ASA score, mean | 2.8 | 3 | 2.8 | 2.8 | 0.49 |
| Previous levels fused | |||||
| 1 | 21 | 3 | 2 | 3 | |
| 2+ | 21 | 20 | 6 | 12 | |
| Levels operated, n | |||||
| T11–T12 | 2 | 1 | 0 | 0 | |
| T12–L1 | 4 | 2 | 0 | 0 | |
| L1–L2 | 13 | 5 | 1 | 1 | |
| L2–L3 | 27 | 11 | 4 | 6 | |
| L4–L5 | 35 | 0 | 1 | 3 | |
| L5–S1 | 32 | 0 | 2 | 2 |
Abbreviations: ASA, American Society of Anesthesiologists;