Table 1 Demographics and clinical data of the study groups
Total cohort (N = 563) | Mini-open partial laminectomy (N = 326) | Minimally invasive laminotomy (N = 237) | p value* | |
|---|---|---|---|---|
Gender | ||||
Female | 268 (48%) | 147 (45%) | 121 (51%) | 0.16 |
Male | 295 (52%) | 179 (55%) | 116 (49%) | |
Age (years) | 64 ± 12 (45 to 75) | 65 ± 10 (45 to 72) | 62 ± 12 (48 to 75) | 0.002 |
BMI (kg/m2) | 29 ± 5 (21 to 34) | 28 ± 4 (21 to 32) | 30 ± 5 (23 to 34) | 0.01 |
Operated segments | ||||
Single level | 485 (86%) | 287 (88%) | 198 (83%) | 0.12 |
L1–L2 | 4 (1%) | 2 (1%) | 2 (1%) | 0.74 |
L2–L3 | 29 (5%) | 20 (6%) | 9 (4%) | 0.21 |
L3–L4 | 61 (11%) | 39 (12%) | 22 (9%) | 0.31 |
L4–L5 | 293 (52%) | 174 (53%) | 119 (50%) | 0.46 |
L5–S1 | 98 (17%) | 52 (16%) | 46 (19%) | 0.28 |
Multi-level | 78 (14%) | 39 (12%) | 39 (17%) | 0.14 |
Two levels | 62 (11%) | 32 (10%) | 30 (13%) | 0.29 |
Three levels | 12 (2%) | 4 (1%) | 8 (3.5%) | 0.08 |
Four levels | 4 (1%) | 3 (1%) | 1 (0.5%) | 0.48 |