Table 2.
Association between synovial fluid white cell count and clinical and imaging parameters at baseline
| Synovial fluid white cell count (cells/mm3) | ||||
|---|---|---|---|---|
| Variable | ≤100 | 101–250 | 251–1000 | |
| Mean (SD) | Mean (SD) | Mean (SD) | p | |
| Age | 61.1 (10.7) | 62.2 (10.8) | 58.7 (8.9) | 0.635 |
| Gender | N (%) | N (%) | N (%) | |
| Male | 15 (71.4) | 15 (68.2) | 6 (50.0) | |
| Female | 6 (28.6) | 7 (31.8) | 6 (50.0) | 0.434 |
|
Maximal Kellgren-Lawerence score in either patellofemoral or tibiofemoral compartment |
||||
| 2 | 8 (38.1) | 7 (33.3) | 4 (44.4) | |
| 3 | 12 (57.1) | 12 (57.1) | 5 (55.6) | |
| 4 | 1 (4.8) | 2 (9.5) | 0 (0) | 0.867 |
| Baseline Pain | ||||
| KOOS pain | 46.3 (16.4) | 49.5 (17.0) | 41.9 (11.0) | 0.405 |
| Nominated VAS | 7.0 (1.7) | 6.6 (2.2) | 7.6 (1.1) | 0.346 |
| MRI Volumetric Assessment | Median (IQR) | Median (IQR) | Median (IQR) | |
| Synovial tissue volume (mm3) | 7771 (6082–9667) | 10670 (6036–13154) | 13934 (7441–20333) | 0.028 |
| Whole knee semi-quantitative assessment | ||||
| Synovitis † | 10.5 (8–13) | 13 (11–14) | 15 (13 – 15.5) | 0.016 |
| Bone marrow lesion‡ | 3 (1.5–6.5) | 5 (4–7) | 8 (7–10.5) | 0.013 |
| Cartilage‡ | 5 (2–10.5) | 11.5 (9–16) | 18 (13.75–19.5) | 0.003 |
| Osteophytes‡ | 20.5 (17–43.5) | 43 (31–53) | 38.5 (29–49.5) | 0.170 |
KOOS scored from 100 (no pain) to 0 (extreme pain), Nominated activity VAS scored from 0 (no pain) - 10 (extreme pain),. Abbreviations: KOOS - Knee Injury and Osteoarthritis Outcome score.
†
Sum of 7 regions (each scored 0–3)
‡
Assessed using the Whole Organ Magnetic Imaging Score. Whole knee scores calculated as the sum of individual compartment scores