saddle joint

your wrists are examples of saddle joints

thumb

1.ball and socket joint

2.hinge joint

3.gliding joint

4.saddle joint

5.ellipsoidal joint

A saddle joint is a joint with saddle-shaped articular surfaces that are convex in one direction and concave in another.
If you are a rider, your body produces the same sort of joint with the saddle that you are riding on.
Saddle joint is also known as a sellar joint as the adjacent surfaces at the ends of each bone are saddle-shaped, with the saddles meeting to form an X shape.