Do Double-Jointed People Have Extra Joints?

Saying someone is 'double-jointed' is misleading. Double-jointed implies that people have more joints. Or, you could interpret 'double-jointed' as having twice normal the motion of one's joints. In fact, neither is true. Double-jointed is simply a way of saying someone has more motion than normal, but it does not mean these people are put together any differently. While there are some medical conditions that can lead to increased joint flexibility, most people who are double jointed simply have more motion in their joints.