Sonographic findings for the common extensor tendon of the elbow in the general population.

OBJECTIVE

To describe structural characteristics and sonographic alterations of the common extensor tendon (CET).

METHODS

In 240 patients, we determined the body mass index; sonographic CET thickness, morphologic characteristics, and alterations; and color Doppler measurements of the epicondylar artery width and peak systolic velocity. Age, sex, epicondylalgia history, activities (work, sports, and hobbies), and dominant and nondominant elbows were noted.

RESULTS

The CET was thicker in the dominant elbow (4.77 versus 4.61 mm [P = .023]), male patients (dominant, 5.09 versus 4.46 mm [P < .001]; nondominant, 5.00 versus 4.21 mm [P < .001]), patients involved in risk activities (dominant, 5.21 versus 4.70 mm [P < .001]; nondominant, 5.12 versus 4.53 mm [P < .001]), and those with a history of epicondylalgia (right, 5.27 versus 4.70 mm [P < .001]; left, 4.86 versus 4.60 mm [P = .316]). Thickness correlated weakly with age (dominant, r = 0.284; nondominant, r = 0.215) and moderately with weight (dominant, r = 0.492; nondominant, r = 0.502). The mean epicondylar artery diameter was 1.35 mm (SD, 0.96 mm); mean peak velocity, 13.01 cm/s (SD, 4.90 cm/s). Morphologic abnormalities were found in 79.5% of patients with a history of epicondylalgia; 7.7% with no history had abnormalities; and 55.9% with abnormalities but no history were older than 55 years. Bone spurs (49.2% versus 16.4% [P < .001]), tendon calcifications (21.5% versus 3.9% [P < .001]), and bone cortex abnormalities (12.3% versus 1.7% [P < .001]) were found more often in non-normal elbows; 79.4% of bone spurs in normal elbows occurred in patients older than 55 years.

CONCLUSIONS

Mild sonographic alterations in the CET and bone spurs should be considered with caution when assessing epicondylar pain, especially in patients older than 55 years and those with a history of epicondylalgia.