Patients and control characteristics. Values are n (%) unless otherwise specified.
| Characteristics | SpA, n = 30 | Athletes, n = 30 | Non-athlete Controls, n = 29 |
|---|---|---|---|
| Age, yrs, mean (SD) | 36.1 (6.8) | 29.3 (8.9) | 30.1 (8.0) |
| Male | 21 (70.0) | 21 (70.0) | 12 (41.4) |
| BMI, mean (SD) | 23.8 (3.5) | 22.2 (2.8) | 22.0 (2.3) |
| Heel pain, ever | 17 (56.3) | 6 (20.0) | 0 |
| CRP, mg/l, mean (SD) | 4.1 (10.8) | 0.7 (2.3) | 1.6 (3.2) |
| HLA-B27+ | 16 (53.3) | 1 (3.3) | 1 (3.4) |
| Radiograph sacroiliitis ≥ 3 unilateral or ≥ 2 bilateral | 26 (86.7) | 0* | 0 |
| Radiograph heel spur | 14 (46.7) | 10 (10.3)* | 7 (24.1) |
↵* 1 missing datum. SpA: spondyloarthritis; BMI: body mass index; CRP: C-reactive protein.