Full Saddle Joint Description
[Continued from above] . . . In this example, the trapezium forms a rounded saddle onto which the first metacarpal sits. The carpometacarpal joint of the thumb makes the human thumb opposable by allowing it to move across the palm to contact the other four fingers of the hand. The opposable thumb is, of course, an extremely important human trait that allows our hand to firmly grip objects and make use of tools.
Prepared by Tim Taylor, Anatomy and Physiology Instructor