Hook Test | Distal Biceps Tendon Rupture Assessment | Biceps Tear

You are probably familiar with the popeye sign that’s characteristic of proximal ruptures of the long head of the biceps tendon. But what may be a clinical sign of injury to the distal biceps tendon? O’Driscoll et al. (2007) proposed the Hook Test and report a sensitivity and specificity of both 100% in their diagnostic cohort study. Devereaux et al. (2013) could replicate the specificity of 100% but report a slightly lower sensitivity of 81%. While the sample sizes were rather small in both studies at 45 patients each, the sound reference standard and setup plus the findings give it a high clinical value in our opinion.

To conduct the test, the patient is either standing or sitting. Then the patient is asked to actively flex the elbow to 90° and to fully supinate the forearm. In the case of the left elbow, use your right index finger and try to hook it under the biceps tendon by bringing it in laterally of the antecubital fossa.
In a normal tendon, you should be able to insert the finger approximately 1cm beneath the tendon or even until the distal interphalangeal joint and be able to pull the tendon forward vigorously.

If the distal biceps tendon is avulsed, you won’t be able to hook your index finger under the tendon, which indicates a positive test.
In a second scenario, pain may be elicited when pulling the intact tendon forward which may suggest a partial tear or other injuries of the tendon or sheath.

Other common orthopedic tests to assess for distal biceps tendon ruptures are:

• Ludington’s Test
• Tilt Sign
• Supination Pronation Test
• Biceps Squeeze Test
• Biceps Crease Interval

Devereaux MW, ElMaraghy AW. Improving the rapid and reliable diagnosis of complete distal biceps tendon rupture: a nuanced approach to the clinical examination. The American journal of sports medicine. 2013 Sep;41(9):1998-2004.

O’Driscoll SW, Goncalves LB, Dietz P. The hook test for distal biceps tendon avulsion. The American journal of sports medicine. 2007 Nov;35(11):1865-9.