Table 1.
Baseline features of all LBP patients in relation to the presence of BME lesions on MRI-spine and on MRI-SIJ.
| Baseline features of all patients with inflammatory LBP | Total patients n = 75 | MRI-SIJ + / MRI-SPINE ±, n = 48 | vs. | MRI-SIJ – / MRI-SPINE ±, n = 27 | p§ | MRI-SPINE + / MRI-SIJ ±, n = 44 | vs. | MRI-SPINE – / MRI-SIJ ±, n = 31 | p§ |
|---|---|---|---|---|---|---|---|---|---|
| Age of onset LBP, mean (± SD) | 28.51 (± 8.05) | 28.44 (± 7.24) | 28.63 (± 9.48) | ns | 28.11 (± 7.92) | 29.06 (± 8.33) | ns | ||
| Male, n (%) | 34 (45.3%) | 27 (56.25%) | 7 (25.93%) | <0.05 | 20 (45.45%) | 14 (45.16%) | ns | ||
| Duration (months) di LBP, mean (± SD) | 13.37 (± 6.14) | 14.25 (± 6.38) | 11.81 (± 5.47) | ns | 13.77 (±.67) | 12.81 (± 5.39) | ns | ||
| Only axial involvement, n (%) | 39 (52%) | 25 (52.08%) | 14 (51.85%) | ns | 25 (56.82%) | 14 (45.16%) | ns | ||
| Axial and peripheral involvment, n (%) | 36 (48%) | 23 (47.92%) | 13 (48.15%) | ns | 19 (43.18%) | 17 (54.84%) | ns | ||
| HLA-B27 positive, n (%) | 29 (38.7%) | 26 (54.17%) | 3 (11.11%) | <0.05 | 19 (43.18%) | 10 (32.26%) | <0.05 | ||
| Positive family history of SpA, n (%) | 35 (46.7%) | 24 (50%) | 11 (40.74%) | ns | 20 (45.45%) | 15 (48.39%) | ns | ||
| Peripheral arthritis, n (%) | 34 (45.3%) | 23 (47.92%) | 11 (40.74%) | ns | 19 (43.18%) | 15 (48.39%) | ns | ||
| Psoriasis, n (%) | 25 (33.3%) | 17 (35.42%) | 8 (29.63%) | ns | 13 (29.55%) | 12 (38.71%) | ns | ||
| Dactylitis, n (%) | 15 (20%) | 8 (16.67%) | 7 (25.93%) | ns | 5 (11.36%) | 10 (32.26%) | ns | ||
| Heel enthesitis, n (%) | 54 (72%) | 33 (68.75%) | 21 (77.78%) | ns | 29 (65.91%) | 25 (80.65%) | ns | ||
| Uveitis, n (%) | 7 (9.3%) | 7 (14.58%) | 0 (%) | <0.05 | 4 (9.09%) | 3 (9.68%) | <0.05 | ||
| IBD, n (%) | 9 (12%) | 4 (8.33%) | 5 (18.52%) | <0.05 | 7 (15.91%) | 2 (6.45%) | <0.05 | ||
| Preceding infections, n (%)† | 4 (5.3%) | 3 (6.25%) | 1 (3.70%) | ns | 2 (4.55%) | 2 (6.45%) | ns | ||
| Good response to NSAIDs, n (%) | 73 (97.3%) | 47 (97.92%) | 26 (96.30%) | ns | 43 (97.73%) | 30 (96.77%) | ns | ||
| Elevated CRP/ESR, n (%) | 42 (56%) | 29 (60.42%) | 13 (48.15%) | <0.05 | 24 (54.55%) | 18 (58.06%) | ns | ||
| Cervical pain, n (%) | 28 (37.3%) | 16 (33.33%) | 12 (44.44%) | ns | 18 (40.91%) | 10 (32.26%) | ns | ||
| Thoracic pain, n(%) | 42 (56%) | 31 (64.58%) | 11 (40.74%) | ns | 25 (56.82%) | 17 (54.84%) | ns | ||
| Buttock pain, n (%) | 48 (64%) | 35 (72.92%) | 13 (48.15%) | <0.05 | 31 (70.45%) | 17 (54.84%) | ns | ||
| Alternating buttock pain, n (%) | 37 (49.3%) | 29 (60.42%) | 8 (29.63%) | <0.05 | 26 (59.10%) | 11 (35.48%) | <0.05 | ||
| Morning stiffness, n (%) | 57 (76%) | 37 (77.08%) | 20 (74.07%) | ns | 36 (81.82%) | 21 (67.74%) | ns | ||
| Night pain, n(%) | 71 (94.7%) | 46 (95.83%) | 25 (92.60%) | ns | 43 (97.73%) | 28 (90.32%) | ns | ||
| Sacroiliitis MRI *, n (%) | 48 (64%) | 48 (100%) | 0 (0%) | <0.05 | 29 (65.91%) | 19 (61.29%) | <0.05 | ||
| Sacroiliitis x-ray **, n (%) | 25 (33.3%) | 19 (39.58%) | 6 (22.22%) | <0.05 | 17 (38.64%) | 8 (25.81%) | <0.05 | ||
| Weight (kg), mean (± SD) | 70.22 (± 16.15) | 71.25 (± 15.87) | 68.05 (± 16.98) | ns | 66.60 (± 11.12) | 75.5 (± 20.65) | ns | ||
| Height (cm), mean (± SD) | 170.6 (± 8.67) | 172.23 (± 8.73) | 167.71 (± 7.91) | ns | 170.41 (± 8.42) | 170.88 (± 9.15) | ns |
HLA-B27, human leukocyte antigen; LBP, low back pain; IBD, inflammatory bowel disease; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; MRI, magnetic resonance imaging; SpA, spondyloarthritis; SIJ, sacroiliac joints; NSAID, non-steroidal antiinflammatory drugs; MRI+, presence of inflammatory lesions; MRI–r, absence of inflammatory lesions; ±, presence or absence of inflammatory lesions.
*
sacroiliitis on MRI according ASAS/EULAR criteria.
**
sacroiliitis on X-Rays according modified New York criteria (0–4).
†
balanitis, urethritis, or cervicitis. p§, anova (Kruskal Wallis) a t0: p < 0.05; SD = deviation standard.