Ultrasonographic evaluation of the posterolateral radiohumeral plica in asymptomatic subjects and in patients with osteoarthritis.

AIMS The aim of this study was to describe the morphological features of posterolateral radiohumeral (RH) plica in asymptomatic subjects and in patients with elbow osteoarthritis using ultrasonography (US). MATERIAL AND METHODS The control group included a total of 100 healthy elbows (51 subjects) and the study group consisted of 22 elbows (22 patients) with osteoarthritis confirmed clinically and by imaging methods. The presence, length, height, thickness, cross sectional area, shape, and echogenicity of the posterolateral RH plica were evaluated in both groups. In addition, humeral and radial cartilage thicknesses were also measured. The clinical characteristics and radiographic findings of the study group were evaluated. RESULTS The posterolateral RH plica was present in all elbows of the control group (100%) and in 15 (68%) of elbows in the study group (p<0.05). All sizes and cross sectional areas of the plica were statistically significantly lower in the elbows of the study group compared to the elbows of the control group (p<0.05 and p<0.001, respectively). The detected posterolateral RH plicae were triangularly shaped in both groups. The plica was hyperechoic in 95 elbows (95%) in the control group and 7 osteoarthritis elbows (46.7%) (p<0.001). The thicknesses of radial and humeral cartilage were also significantly higher in the control group (p<0.001). There were no statistically significant relationships between the radiographic scoring of the elbow osteoarthritis and US findings of the RH plica (all p>0.05). CONCLUSIONS The posterolateral RH plica can be successfully evaluated using US. Based on these findings, it appears that osteoarthritis can result in a reduction of the RH plica and affect its morphological appearance.