Radius (bone) Radius (bone) The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The radius is shorter and smaller than the ulna. It is a long bone, prism-shaped and slightly curved longitudinally. The radius is part of two joints: the elbow and the wrist. At the elbow, it joins with the capitulum of the humerus, and in a separate region, with the ulna at the radial notch. At the
Forearm (comics) "the boy". Forearm was also featured in a "What If" issue that asks "What If Magneto Took Over the USA." He is shown as a member of the MLF. In this storyline, Magneto killed Stryfe and coerced the remaining members of MLF to follow him. Forearm was also killed during this reality in an explosion. Forearm (comics) Forearm (Michael McCain) is a fictional mutant villain appearing in American comic books published by Marvel Comics. As a member of the Mutant Liberation Front, Forearm has always been a mainstay on the terrorist group's roster, even staying through leader changes and incarceration.