Bony landmark · Elbow

Radial tuberosity

Tuberositas radii

The radial tuberosity is an oval bump on the inner side of the radius, an inch or so below its head. The biceps brachii inserts here, and because the radius is the bone that rotates, that one attachment gives the biceps two jobs at once: it bends the elbow and it rolls the palm face-up. This is why a right-handed person turns a corkscrew clockwise — it is the direction the strongest arm muscle pulls.