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Double-Jointed? Nope, There’s No Such Thing

You have hypermobility syndrome.

| 2 min read

You have hypermobility syndrome.

If you’re not one of them, you definitely know some people who claim to be “double-jointed” and can bend their fingers or other body parts in freakishly bizarre ways. However, it turns out that there’s actually no such thing as being double-jointed.

Being double-jointed would imply that people with unusual flexibility have extra joints in those places which allow for these bendy movements. But having twice the average number of joints truly only occurs in extremely rare cases — other than that, it’s anatomically impossible, reports LiveScience.

So what’s the explanation then for these crazily bendy people? They actually have something called hypermobility syndrome, a condition which allows people to move a bone within a joint to its fullest capability. While the average person would likely experience discomfort or pain when trying to extend a joint beyond its normal range, those with hypermobility syndrome will have no problems.

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This unusual flexibility also has a lot to do with the tissue near the joints. In fact, this soft tissue can have more of an effect on an individual’s bendiness than the actual joints themselves. While everyone’s joints have the same range of motions, it’s the flexibility of the ligaments and tendons that can determine whether people will be super bendy or unable to even touch their toes.

The shape of the bones at a joint can also influence a person’s flexibility, and the body has several different types of joints. Some are completely immovable, like the joints of your skull, while the synovial joints are highly movable. The most mobile synovial joint of all is the ball-and-socket joint, which can be found in your shoulders and hips, giving your arms and legs a wide range of motion. Basically, the shallower a socket, the more mobile the joint. So people with hypermobility syndrome often have unusually shallow sockets.

In the most extreme cases of hypermobility, people can painlessly dislocate their shoulders. This is when the “ball” part can be moved partially or completely out of the socket — even though it’s painless, watching it will probably make you cringe.

See for yourself in the video below. A 17-year-old contestant on Britain’s Got Talent, nicknamed Bonetics, contorts his body into unimaginable positions. While most people would say he must be crazily double-jointed, now you can correct the common misconception. But either way, his ultra-flexibility still might give you goosebumps.



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