Prevalence of knee synovitis on ultrasonography in subjects with painful knee OA
Ultrasonographic knee synovitis* | p Value† | |||
---|---|---|---|---|
Absent | Present | |||
*Knee synovitis was defined as “present” if synovial thickness was ⩾4 mm with diffuse or nodular appearance. †p Values refer to comparisons between subgroups with or without synovitis (Student’s t test for quantitative variables and χ2 test for qualitative variables). | ||||
Total number of subjects, No (%) | 500 (83.3) | 100 (16.7) | ||
Synovial thickness (mm) | <0.0001 | |||
Mean (SD) | 1.3 (1.5) | 5.8 (3.0) | ||
Median (range) | 1 (0–19) | 5 (4–29) | ||
Appearance of synovial tissue, No (%) | <0.0001 | |||
Absent | 278 (55.6) | 0 (0) | ||
Nodular | 75 (15.0) | 56 (56.0) | ||
Diffuse | 147 (29.4) | 44 (44.0) | ||
Maximal effusion depth (mm) | <0.0001 | |||
Mean (SD) | 3.4 (4.5) | 6.9 (3.9) | ||
Median (range) | 2.7 (0–20) | 6.1 (0–71) |