Table 1:
Demographics of chronic low back pain patients and asymptomatic control subjects.
| Characteristic | Control subjects (n = 18) | Back pain patients (n = 42) | P value |
|---|---|---|---|
| Age (y) | 42.7 ± 12.8 | 48.0 ± 12.4 | 0.15 |
| Male | 10 (55.5) | 21 (50.0) | 0.69 |
| Weight (kg) | 71.3 ± 12.7 | 76.6 ± 17.6 | 0.21 |
| Height (cm) | 173.7 ± 10.0 | 173.3 ± 9.9 | 0.89 |
| BMI (kg/m2) | 23.6 ± 4.2 | 25.5 ± 4.9 | 0.17 |
| Clinical measures | |||
| ODI | 0 ± 0 | 33.3 ± 14.4 | <0.001 |
| VAS | 0 ± 0 | 6.6 ± 1.7 | <0.001 |
| Pfirrmann grade | 2.2 ± 1.0 | 3.0 ± 1.1 | < 0.001 |
| MC 1 | 0 (0) | 26 (5.9) | <0.001 |
| MC 2 | 2 (1.3) | 47 (11.2) | <0.001 |
| MC 3 | 0 (0) | 0 (0) | 0.99 |
For all characteristics except male sex and number of levels with each type of MC, data are shown as mean ± SD. Data in parentheses are percentages. Independent t tests were used to compare the differences between two groups for continuous numerical variables. χ2 tests were used to compare the differences between two groups for sex and for the clinical measures. BMI = body mass index; ODI = Oswestry Disability Index score; VAS = Visual Analog Scale score; MC = Modic changes.