Blue Box Stuff from Moore - University of California, Los ...

The two bones in the forearm are the radius and the ulna. The radius is on the thumb-side of the forearm. The upper end of the radius is called the radial head. The radial head is kept in place by a ligament called the annular ligament. When the annular ligament is torn, a part of it slides upward and gets trapped in the elbow joint. ................
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