Detailed data on the prevalence of lesions as assessed by PDUS or MRI
| Imaging | Site | Heel | pSpA (n=37) | Non-SpA (n=34) | P value |
| PDUS | Plantar fascia | Tendon rupture (total or partial) | 0 | 0 | – |
| Accompanying bone erosion | 2 (5.4%) | 1 (2.9%) | 0.609 | ||
| Calcification/enthesophyte | 5 (13.5%) | 1 (2.9%) | 0.112 | ||
| Inflammatory signal (intratendinous) | 1 (2.7%) | 2 (5.9%) | 0.509 | ||
| Achilles’ tendon | Tendon rupture (total or partial) | 1 (2.7%) | 2 (5.9%) | 0.509 | |
| Accompanying bone erosion | 22 (59.5%) | 9 (26.5%) | 0.008 | ||
| Calcification/enthesophyte | 5 (13.5%) | 3 (8.8%) | 0.535 | ||
| Inflammatory signal (intratendinous) | 12 (32.4%) | 10 (29.4%) | 0.785 | ||
| MRI | Plantar fascia | Tendon rupture (total or partial) | 1 (2.7%) | 2 (5.9%) | 0.509 |
| Accompanying bone erosion | 5 (13.5%) | 2 (5.9%) | 0.285 | ||
| Calcification/enthesophyte | 3 (8.1%) | 1 (2.9%) | 0.349 | ||
| Inflammatory signal (peritendinous) | 9 (24.3%) | 11 (32.4%) | 0.456 | ||
| Inflammatory signal (intratendinous) | 3 (8.1%) | 4 (11.8%) | 0.608 | ||
| Inflammatory signal (bone marrow oedema) | 3 (8.1%) | 2 (5.9%) | 0.716 | ||
| Achilles’ tendon | Tendon rupture (total or partial) | 0 | 0 | – | |
| Accompanying bone erosion | 12 (32.4%) | 10 (29.4%) | 0.785 | ||
| Calcification/enthesophyte | 0 | 0 | – | ||
| Inflammatory signal (peritendinous) | 16 (43.2%) | 18 (52.9%) | 0.417 | ||
| Inflammatory signal (intratendinous) | 7 (18.9%) | 5 (14.7%) | 0.638 | ||
| Inflammatory signal (bone marrow oedema) | 7 (18.9%) | 6 (17.6%) | 0.891 |