Abstract
BACKGROUND: Manual workers are at risk of developing lateral elbow tendinopathy (LET). We aimed to validate the hypothesis that asymptomatic elbows of manual workers with LET are more likely to have positive physical examination results and morpho-mechanical changes on elbow ultrasonography compared to healthy individuals. METHODS: This cross-sectional case-control study included 30 manual workers with unilateral LET (LET group) and 30 age- and sex-matched healthy volunteers (control group). Demographic data collection and functional evaluation were performed using the Disabilities of the Arm, Shoulder, and Hand; Patient-Rated Tennis Elbow Evaluation; and European Quality of Life Five-Dimensions questionnaires. Physical examination of the elbows and evaluation of the common extensor tendon (CET) with B-mode morphology ultrasonography and Young's modulus elastography were performed. The LET-unaffected and LET-affected elbows in the LET group were compared with the elbows in the control group. RESULTS: The LET-unaffected elbows in the LET group had a higher prevalence of positive chair test results and focal hypoechoic change and microcalcification on ultrasonography than those in the control group (P < 0.05, 0.005, and 0.05, respectively). In addition, LET-affected elbows showed higher focal hypoechoic change, microcalcification, erosive cortex, and neovascularity than elbows in the control group (P < 0.001, 0.001, 0.005, and 0.001, respectively). The unaffected and affected elbows showed greater CET thickness than those in the control group (P < 0.05 and 0.005). CONCLUSION: The unaffected elbows of manual workers with unilateral LET should be considered at risk of LET. We proposed a risk assessment and surveillance protocol based on chair test results and abnormal ultrasonographic findings.