Power Doppler ultrasonography (PDUS) findings at baseline
| PDUS findings | All (n=118) | SpA (n=51) | Non-SpA (n=48) | p Value* | Not classified (n=19) |
|---|---|---|---|---|---|
| Number of abnormal entheses/total enthesis (%) | 436/1652 (26) | 227/714 (32) | 133/672 (20) | <0.01 | 76/266 (29) |
| At least 1 abnormal enthesis, no patients (%) | 88 (75) | 44 (86) | 29 (60) | 0.003 | 15 (79) |
| Abnormal enthesitic sites, % of patients (% of abnormal enthesis/patient) | |||||
| Plantar fascia | 30 (25) | 35 (30) | 19 (18) | NS | 32 (31) |
| Achilles tendon | 38 (33) | 51 (43) | 25 (21) | 0.01 | 37 (26) |
| Patellar ligament | 52 (45) | 61 (51) | 42 (36) | NS | 52 (10) |
| Quadriceps tendon | 32 (28) | 37 (31) | 29 (26) | NS | 32 (28) |
| Gluteus medium tendon | 11 (10) | 14 (12) | 8 (7) | NS | 11 (3) |
| Lateral epicondyle | 32 (28) | 43 (37) | 21 (18) | 0.03 | 31 (28) |
| Medial epicondyle | 17 (16) | 20 (18) | 12 (11) | NS | 21 (18) |
| Global score, median (minimum-maximum)† | 6 (0–42) | 9 (0–42) | 2.5 (0–25) | 0.0005 | 6 (0–28) |
| Number of vascularised entheses/abnormal enthesis (%) | 108/436 (25) | 83/227 (37) | 13/133 (10) | <0.0001 | 12/76 (16) |
| At least one vascularised enthesis, n (%) patients | 56 (47) | 39 (76) | 9 (19) | <0.0001 | 8 (42) |
↵* p Values refer to comparisons between SpA and non-SpA patients. χ2 and Cochrane- Armitage trend test were used, as appropriate.
↵† Global score: this scoring system classifies the severity of each site of enthesitis into six grades (0–5). For each patient the PDUS global score obtained by summing the score of all entheses varied from 0 to 70.
SpA, spondylarthritis.