Table 2. Baseline Characteristics of the Study Population by Lumbar Segmental Instability Status.
| Variable | Total (n = 151) | LSI unstable (n = 72) | LSI stable (n = 79) | P value |
|---|---|---|---|---|
| Age, years | 64.52 ± 9.76 | 63.81 ± 8.47 | 65.16 ± 10.81 | 0.372 |
| Sex, male, n (%) | 33/151 (21.85%) | 13/72 (18.06%) | 20/79 (25.32%) | 0.330 |
| BMI, kg/m2, mean ± SD | 26.33 ± 4.20 | 27.42 ± 4.19 | 25.35 ± 4.00 | 0.002 |
| Hypertension, n (%) | 61/151 (40.40%) | 36/72 (50%) | 25/79 (31.65%) | 0.030 |
| Diabetes, n (%) | 57/151 (37.75%) | 32/72 (44.44%) | 25/79 (31.65%) | 0.077 |
| Smoking, n (%) | 17/151 (11.26%) | 6/72 (8.33%) | 11/79 (13.92%) | 0.409 |
| Alcohol, n (%) | 13/151 (8.61%) | 5/72 (6.94%) | 8/79 (10.13%) | 0.567 |
| max FJE, mm, median (IQR) | 1.16 (2.78) | 2.81 (0.963) | 0.00 (0.500) | < 0.001 |
| FJE present, n (%) | 88/151 (58.28%) | 67/72 (93.06%) | 21/79 (26.59%) | < 0.001 |
| VAS, median (IQR) | 3 (2) | 5 (1) | 3 (1) | < 0.001 |
Values are presented as mean ± standard deviation (SD) or median (interquartile range, IQR) for continuous variables, and n (%) for categorical variables. Tests used: independent t-test for normally distributed continuous variables; Mann–Whitney U test (MW) for non-normal continuous variables; Pearson’s χ2 test or Fisher’s exact test for categorical variables as appropriate. P values two-sided. max FJE: maximum facet joint effusion (mm); LSI: lumbar segmental instability (LSI = 1: unstable; 0: stable). For reproducibility: dataset variable names are max_FJE and instability_bin. BMI: body mass index; FJE: facet joint effusion; LSI: lumbar spine instability; VAS: Visual Analog Scale.