Ultrasound of the elbow: lateral aspect
by Dr Aurélien LAMBERT



To identify the various epicondylar tendons, we start with a longitudinal section along the forearm axis and set the probe proximally. Here, we can see the insertion of the extensor carpi radialis longus, which is unique in that it doesn’t have a true tendon, only muscle and bone. If we move down a few millimeters, we can see a relatively thin tendon – depending on the size of the patient – which is the extensor carpi radialis brevis tendon. A very typical feature is seen here: an important Vshaped landmark between the extensor carpi radialis brevis tendon superficially and the extensor digitorum communis tendon deeply, with these two branches being separated by the muscle belly of the extensor digitorum communis.
A little lower and right behind the extensor digitorum communis, you will find the extensor digiti minimi and deeper, the supinator tendon, which covers the humeroradial joint space.
Even deeper, we can play with the anisotropy and reveal the humeroradial ligament.
The next step of the exam is to make axial sections by turning the probe 90°, which will uncover the epicondylar ridge, here. Behind the ridge, we find the fibers of the extensor carpi ulnaris tendon.