Background In this study, we have included 29 patients with knee osteoarthritis. We analyzed whether the presence and/or intensity of pain were associated with the presence of US joint effusion.
Objectives The aim of this study was to search eventual association between ultrasonographic (US) knee effusion and pain in patients with knee osteoarthritis (OA).
Methods 29 patients (mean age 59.5 [50-76] ± 8.7 years) with bilateral knee OA according to ACR criteria (median 24 months of evolution (11.48)) were included. Pain was measured by the visual analog scale from 0 to 10 cm. A knee US examination was performed in all patients by a blinded rheumatologist with good experience in ultrasonography. The effusion was searched in three regions: the sub-quadriceps cul-de-sac, the medial and lateral patellar retinacula. We analyzed whether the presence and/or intensity of pain were associated with the presence of US joint effusion.
Results 58 osteoarthritic knees were studied. Pain on clinical examination was found on 44 knees (75.9%). The intensity of pain assessed by VAS of pain was 54.5 [10-80] ± 20.4. The joint effusion was present on ultrasound in 23 knees (39.7%) and was located in the sub-quadriceps cul-de-sac, the medial and lateral patellar retinacula respectively in 27.6%, 25.9% and 8.6% of knees evaluated. We found no association between pain presence and US effusion (p: NS). The pain intensity was also comparable in both groups with and without US joint effusion (49.1% ± 19.5% vs 58±20.5; p: NS).
Conclusions This study suggests that US joint effusion in patients with knee osteoarthritis is not associated neither with presence nor with intensity of pain. It would be interesting to verify these results with larger studies.
Disclosure of Interest None Declared