The biceps brachii muscle is a multi-joint muscle that spans both the shoulder and the elbow, meaning it has a role in movement at both of these joints. Its main action is elbow flexion (bending the elbow), but it also has many secondary actions such as forearm supination (turning the palm up), and shoulder flexion (raising the arm overhead).

A biceps tendon rupture denotes an injury where the biceps muscle is subjected to excessive loads and detaches from one or more of its proximal attachment sites.

The most common locations for a biceps tendon rupture are at the proximal attachment of the long head (where it connects to the glenoid labrum), and distally where the tendon inserts into the radius.