Background: To investigate the prevalence of Baker's cysts (BCs) in patients with gouty arthritis of the knee using high-resolution musculoskeletal ultrasound (MSUS). To the best of our knowledge, this is the first report in the literature.Methods: We retrospectively reviewed clinical and MSUS data of 103 consecutive patients with gouty arthritis of the knee and 150 patients with knee osteoarthritis examined as a control group. They all had crystal confirmation of gout after joint aspiration. The correlation of the presence of BCs with the presence of joint effusion, synovitis, the double-contour sign, tendinopathy, and tophi was analyzed.Results: BCs were demonstrated by MSUS in 28 (27.1%) of the 103 patients. Only 10 (35.7%) of the 28 cysts had been clinically diagnosed. Joint effusion, synovitis, the double-contour sign, tendinopathy, and tophi were respectively detected in 96.1%, 77.6%, 32.0%, 4.9%, and 7.8% of knees. There was a significant correlation between the presence of BCs and synovitis (p<0.05). There was no significant correlation between the presence of BCs with effusion, the double-contour sign, tendinopathy, and tophi (p>0.05). Two ruptured BCs were observed.Conclusions: These results indicated that BCs are common in patients with gouty arthritis, and that they can easily escape clinical detection. Therefore, MSUS should be more widely employed by clinicians for diagnosis and treatment selection for BCs, which may sometimes be accompanied by significant morbidity, and thus help choose an appropriate treatment.
Background: To investigate the prevalence of Baker's cysts (BCs) in patients with gouty arthritis of the knee using high-resolution musculoskeletal ultrasound (MSUS). To the best of our knowledge, this is the first report in the literature.Methods: We retrospectively reviewed clinical and MSUS data of 103 consecutive patients with gouty arthritis of the knee and 150 patients with knee osteoarthritis examined as a control group. They all had crystal confirmation of gout after joint aspiration. The correlation of the presence of BCs with the presence of joint effusion, synovitis, the double-contour sign, tendinopathy, and tophi was analyzed.Results: BCs were demonstrated by MSUS in 28 (27.1%) of the 103 patients. Only 10 (35.7%) of the 28 cysts had been clinically diagnosed. Joint effusion, synovitis, the double-contour sign, tendinopathy, and tophi were respectively detected in 96.1%, 77.6%, 32.0%, 4.9%, and 7.8% of knees. There was a significant correlation between the presence of BCs and synovitis (p<0.05). There was no significant correlation between the presence of BCs with effusion, the double-contour sign, tendinopathy, and tophi (p>0.05). Two ruptured BCs were observed.Conclusions: These results indicated that BCs are common in patients with gouty arthritis, and that they can easily escape clinical detection. Therefore, MSUS should be more widely employed by clinicians for diagnosis and treatment selection for BCs, which may sometimes be accompanied by significant morbidity, and thus help choose an appropriate treatment.