Proportions of patients with lesions seen on MRI of the spine, stratified by age
| Patients with age at onset chronic back pain <35 years | |||||
|---|---|---|---|---|---|
| ASAS classification 2/3 readers | No SpA | Possible axSpA | Clinical arm only | MRI+mNY− | mNY+ |
| No. of patients | 41 | 55 | 41 | 36 | 20 |
| Inflammatory lesions ≥1 | 12 | 11 | 13 | 18 | 11 |
| % | 29.3 | 20.0 | 31.7 | 50.0 | 55.0 |
| Inflammatory lesions ≥2 | 3 | 7 | 7 | 12 | 10 |
| % | 7.3 | 12.7 | 2.1 | 33.3 | 50.0 |
| Inflammatory lesions ≥3 | 2 | 1 | 2 | 10 | 8 |
| % | 4.8 | 1.8 | 4.8 | 27.8 | 40.0 |
| Fatty lesions ≥1 | 8 | 8 | 6 | 15 | 9 |
| % | 19.5 | 14.5 | 14.6 | 41.7 | 45.0 |
| Fatty lesions ≥2 | 4 | 5 | 5 | 9 | 7 |
| % | 9.8 | 9.1 | 12.2 | 25.0 | 35.0 |
| Fatty lesions ≥3 | 3 | 3 | 3 | 6 | 5 |
| % | 7.3 | 5.5 | 7.3 | 16.7 | 25.0 |
| Fatty lesions ≥3 | 2 | 2 | 2 | 5 | 4 |
| % | 4.8 | 3.6 | 4.8 | 13.9 | 20.0 |
| Erosions ≥1 | 9 | 12 | 14 | 9 | 4 |
| % | 22.0 | 21.8 | 34.1 | 25.0 | 20.0 |
| Erosions ≥2 | 3 | 3 | 4 | 4 | 3 |
| % | 7.3 | 5.5 | 9.8 | 11.1 | 15.0 |
| Erosions ≥3 | 3 | 1 | 4 | 1 | 2 |
| % | 7.3 | 1.8 | 9.8 | 2.8 | 10.0 |
| Erosions ≥4 | 1 | 1 | 1 | 1 | 1 |
| % | 2.4 | 1.8 | 2.4 | 2.8 | 5.0 |
| Syndesmophytes ≥1 | 8 | 12 | 6 | 12 | 1 |
| % | 19.5 | 21.8 | 14.6 | 33.3 | 5.0 |
| Syndesmophytes ≥2 | 3 | 5 | 4 | 4 | 0 |
| % | 7.3 | 9.1 | 9.8 | 11.1 | – |
| Syndesmophytes ≥3 | 2 | 3 | 3 | 1 | 0 |
| % | 4.8 | 5.5 | 7.3 | 2.8 | – |
| Patients with age at onset chronic back pain between 35 and 45 years | |||||
|---|---|---|---|---|---|
| ASAS classification 2/3 readers | No SpA | Possible axSpA | Clinical arm only | MRI+mNY− | mNY+ |
| No. of patients | 28 | 34 | 12 | 15 | 2 |
| Inflammatory lesions ≥1 | 13 | 18 | 6 | 9 | 1 |
| % | 46.4 | 52.9 | 50.0 | 60.0 | 50.0 |
| Inflammatory lesions ≥2 | 12 | 12 | 4 | 6 | 1 |
| % | 42.9 | 35.3 | 33.3 | 40.0 | 50.0 |
| Inflammatory lesions ≥3 | 9 | 9 | 4 | 2 | 1 |
| % | 32.1 | 26.5 | 33.3 | 13.3 | 50.0 |
| Inflammatory lesions ≥4 | 5 | 7 | 3 | 2 | 1 |
| % | 17.9 | 20.6 | 25.0 | 13.3 | 50.0 |
| Inflammatory lesions ≥5 | 2 | 4 | 1 | 2 | 1 |
| % | 7.1 | 11.8 | 8.3 | 13.3 | 50.0 |
| Inflammatory lesions ≥6 | 1 | 2 | 1 | 2 | 0 |
| % | 3.6 | 5.9 | 8.3 | 13.3 | – |
| Fatty lesions ≥1 | 10 | 16 | 7 | 9 | 2 |
| % | 35.7 | 47.1 | 58.3 | 60.0 | 100.0 |
| Fatty lesions ≥2 | 7 | 11 | 3 | 8 | 2 |
| % | 25.0 | 32.4 | 25.0 | 53.3 | 100.0 |
| Fatty lesions ≥3 | 6 | 6 | 0 | 7 | 1 |
| % | 21.4 | 17.6 | – | 46.7 | 50.0 |
| Fatty lesions ≥4 | 4 | 5 | 0 | 6 | 0 |
| % | 14.3 | 14.7 | – | 40.0 | – |
| Fatty lesions ≥5 | 3 | 4 | 0 | 6 | 0 |
| % | 10.7 | 11.8 | – | 40.0 | – |
| Fatty lesions ≥6 | 2 | 4 | 0 | 5 | 0 |
| % | 7.1 | 11.8 | – | 33.3 | – |
| Fatty lesions ≥7 | 1 | 4 | 0 | 2 | 0 |
| % | 3.6 | 11.8 | – | 13.3 | – |
| Erosions ≥1 | 14 | 12 | 2 | 6 | 1 |
| % | 50.0 | 35.3 | 16.7 | 40.0 | 50.0 |
| Erosions ≥2 | 7 | 7 | 1 | 4 | 1 |
| % | 25.0 | 20.6 | 8.3 | 26.7 | 50.0 |
| Erosions ≥3 | 2 | 3 | 0 | 3 | 1 |
| % | 7.1 | 8.8 | – | 20.0 | 50.0 |
| Erosions ≥4 | 1 | 3 | 0 | 1 | 0 |
| % | 3.6 | 8.8 | – | 6.7 | – |
| Syndesmophytes ≥1 | 9 | 9 | 2 | 7 | 1 |
| % | 32.1 | 26.5 | 16.7 | 46.7 | 50.0 |
| Syndesmophytes ≥2 | 3 | 6 | 1 | 2 | 0 |
| % | 10.7 | 17.6 | 8.3 | 13.3 | – |
| Syndesmophytes ≥3 | 3 | 4 | 0 | 2 | 0 |
| % | 10.7 | 11.8 | – | 13.3 | – |
| Syndesmophytes ≥4 | 0 | 2 | 0 | 1 | 0 |
| % | – | 5.9 | – | 6.7 | – |
False positives ≤10% in italic; false positives ≤5% in italic and bold.
ASAS, Assessment of Spondyloarthritis international Society; axSpA, axial spondyloarthritis; mNY, modified New York criteria; SpA, spondyloarthritis.