Table 2 Demographic characteristics and ultrasound pathology findings in each of four pathology groups
|  | Bursitis (limited inflammation) (n = 1280) | Bursitis (extensive inflammation) (n = 595) | RC tear (n = 558) | Limited pathology (n = 567) |
|---|---|---|---|---|
Percentage of sample | 43% | 20% | 18% | 19% |
Age, years, mean (SD) | 47.6 (11.5) | 64.2 (10.5) | 69.1 (11.2) | 46.1 (13.5) |
Female sex, % | 54 | 52 | 51 | 46 |
Pain duration, months,a median (IQR) | 5 (3–10) | 5 (3–9) | 5 (3–9) | 4 (3–8) |
Steroid injection at time of scan, % | 44 | 37 | 13 | 26 |
RC tear, yes/no, % | 2 | 24 | 100 | 6 |
Full-thickness RC tear, % | 1 | 13 | 86 | <1 |
Bursitis, % | 100 | 94 | 30 | 7 |
Impingement, % | 88 | 65 | 91 | 6 |
Calcific tendinitis, % | 14 | 18 | 5 | 9 |
ACJ degeneration, % | 26 | 83 | 54 | 15 |
Glenohumeral OA, % | <1 | 10 | 16 | 2 |
Adhesive capsulitis, % | <1 | 3 | <1 | 12 |
Biceps tenosynovitis, % | <1 | 25 | 10 | 2 |
Rotator cuff tendinopathy, % | 23 | 92 | 24 | 20 |
Probability of membership, mean | 0.88 | 0.80 | 0.89 | 0.93 |