Table 1.
Demographic characteristics, coexisting illnesses and measures of health status for both groups (n = 3,245)
| Variable | Adolescents (age <20), n = 97 | Adults (age 20–50), n = 3,148 | p value |
|---|---|---|---|
| Mean age, years ± SD | 17.5 ± 1.6 | 37.6 ± 7.7 | <0.001 |
| Female sex, no. (%) | 48 (49.5) | 1271 (40.4) | 0.072 |
| BMI ± SDa | 24.4 ± 4.1 | 26.5 ± 4.4 | <0.001 |
| Daily tobacco smoking, no. (%) | 13 (13.4) | 955 (30.7) | <0.001 |
| ASA grade >2b | 0 (0) | 47 (1.5) | 0.224 |
| Preoperative ODI ± SDc | 33.9 ± 13.0 | 41.3 ± 16.6 | <0.001 |
| Preoperative EQ-5D ± SD | 0.38 ± 0.34 | 0.34 ± 0.34 | 0.265 |
| Preoperative leg pain (NRS) ± SD | 6.3 ± 2.2 | 6.5 ± 2.2 | 0.525 |
| Preoperative back pain (NRS) ± SD | 5.6 ± 2.5 | 5.8 ± 2.3 | 0.333 |
| Preoperative paresis, no. (%) | 2 (2.1) | 342 (10.9) | 0.006 |
| Duration of leg pain >1 year, no. (%) | 28 (29.5) | 720 (24.0) | 0.221 |
aThe bodymass index (BMI) is the weight in kilograms divided by the square of the height in metres
bThe American Society of Anesthesiologists (ASA) grade ranges from I to V; grade V is the worst, indicating life-threating condition
cOswestry Disability Index (ODI) ranges from 0 to 100; lower scores indicating less severe symptoms