Why Is Hitting Your “Funny Bone” So Painful?

The only thing funny about your funny bone is that it's not a bone. That tender spot right by your elbow, which puts a grimace – not a grin – on your face when you hit it just right, is actually the location of easy exposure to your ulnar nerve, a bundle of fibers that runs from your spine to your ring and pinky fingers.

While the ulnar nerve is mostly protected by bone and muscle, there's that one spot on your arm where it's not. For that reason, if you strike it just right, you basically squish the nerve fibers against your medial epicondyle, resulting in that unnerving (no pun intended) feeling, which is somewhere between pain and numbness.

Luckily for most of us, the annoyance goes away pretty quickly, unless you happen to suffer from cubital tunnel syndrome. For those unfortunate souls, the feeling is much more common, occurring because they have kept their elbow in a bent position for too long or simply because they are more susceptible to the condition. In those cases, if some minor changes don't work – like putting on a splint to keep the arm straight during sleep – surgery might be necessary.

How well do you know your body?