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What is the name of the of joint at the base of the thumb?
The base of the thumb, the first phalanx, makes a joint with a carpal bone called the trapezium, and the two articulate in a special joint called a saddle joint. You only have tow of these in your body, one at the base of each thumb.
The joint at the base of your thumb is the metacarpal phalangeal joint. It is an ellipsoidal joint. And if you follow it to the base of the First metacarpal, you will find the only saddle joint in...