Objective. To describe the sonographic findings of distal biceps tendon rup
tures and to assess the accuracy of the technique. Methods. Twenty-five pat
ients with clinically indicated distal biceps tendon ruptures were prospect
ively studied by sonography. Five patients also underwent magnetic resonanc
e imaging. Surgical confirmation was obtained in 14 patients. Results. Seve
nteen complete tendon ruptures and 3 partial tears were correctly shown by
sonography; 1 complete rupture was incorrectly shown as a partial tear by s
onography. Sonographic features of complete rupture were absence of tendon
in the expected location, fluid collection in a typical tendon gap, and a m
ass in the antecubital fossa. Sonographic features of incomplete rupture we
re intratendinous hypoechogenicity and tendon thinning. Peritendinous fluid
was found in complete and incomplete ruptures. Conclusions. In distal bice
ps tendon ruptures, sonography is a cost-effective method that can confirm
the clinical indications with good accuracy and can show tendon lesions whe
n the clinical indications are low.