Ultrasonographic Measurement of Thickness of Extensor Carpai Radialis Brevis Tendons for Lateral Epicondylitis

Purpose: To evaluate the ultrasonographic measurements of the thickness of the extensor carpai radialis brevis tendons in patients with lateral epicondylitis. Materials and Methods: Twenty nine patients diagnosed with lateral epicondylitis were examined prospectively. Eight were male and twenty one were female. The mean age was 48 (34-62) years. The average time from the onset of symptoms until the examination was 9 (1-24) months. Eighteen patients did not show improvement in their symptoms after conservative treatment. Six underwent arthroscopic debridement and 4 underwent electric shock wave therapy. Three patients showed calcification on the simple x-ray. The thickness of the extensor carpai radialis brevis tendons on both the lesion and contralateral sides was measured and compared using ultrasonography. Results: There were no significant differences in age and gender between the thickness of the extensor carpai radialis brevis tendons on the lesion and contralateral sides (p=0.83, 0.25, 0.80, 0.64). The thickness of the extensor carpai radialis brevis tendons on the lesion and contralateral sides were 4.9 mm and 3.2 mm, respectively, and the lesion side was significantly thicker (p<0.001). The best cut off value of the ECRB thickness at its origin was 3.95 mm, which had a sensitivity, specificity and accuracy of 96.6%, 79.3% and 87.9%, respectively. Conclusion: Sonographic measurements of the thickness of the ECRB tendons are valuable for diagnosing lateral epicondylitis.