| Without alterations | 452 (35.2) | 6 (0.5) | 3 (0.2) |
| Degenerative changes of the SIJ | 152 (11.8) | 37 (2.9) | 5 (0.4) |
| Sacroiliitis with erosions | 147 (11.5) | | |
| Sacroiliitis BME + erosions | 157 (12.2) | 11 (0.9) | |
| Degenerative disc disease L5-S1 | 103 (8) | 141 (11) | 12 (0.9) |
| BME (without ASAS criteria) | 82 (6.4) | 32 (2.5) | 4 (0.3) |
| Sacroilitis with BME | 73 (5.7) | | |
| Other | 40 (3.1) | 29 (2.3) | 7 (0.5) |
| Lumbosacral transition abnormality | 18 (1.4) | 27 (2.1) | 10 (0.8) |
| Osteitis condensans ilii | 17 (1.3) | 7 (0.5) | 2 (0.2) |
| Fracture | 12 (0.9) | 2 (0.2) | |
| Tumor | 16 (1.2) | 4 (0.3) | |
| Diffuse idiopathic skeletal hyperostosi (DISH) | 6 (0.5) | 1 (0.1) | 1 (0.1) |
| Anatomical variants of SIJ | 6 (0.5) | 11 (0.9) | 1 (0.1) |
| Septic Arthritis | 2 (0.2) | | |
| Gout | | 1 (0.1) | |