The “funny bone” is neither funny (especially when you bang it on a table or wall), nor is it a bone (regardless of whether you bang it or not). So, where’d the name “funny bone” come from, and why is it so painful?
When you talk about your “funny bone”, you’re actually talking about your ulnar nerve. Your ulnar nerve runs from your neck all the way to down to your hand, where it does what’s called “innervates” several different hand & forearm muscles before ending up in two final branches that innervate your pinkie & part of your ring finger.
Much like the rest of the nerves in your body, the majority of your ulnar nerve is protected by bones, muscles, and/or ligaments. But, as the ulnar nerve passes your elbow, it runs through a channel called the cubital tunnel. And, at that point, it’s only protected by skin & fat, and that makes it vulnerable to getting bumped. So, whenever you hit your “funny bone”, you’re actually hitting the ulnar nerve against bone & compressing it, and that results in a weird mixture of numbness, tingling, and pain that shoots through the areas where the nerve does its thing (down your forearm & hand, into your ring & pinky fingers.
But, why is it called the “funny bone”? Well, there are two schools of thought in that debate. Some experts believe it to be an anatomical pun, since the ulnar nerve runs along the humerus bone, which sounds like the word “humorous” (as in funny). Other folks claim this particular nerve got its nickname because of the funny (as in odd) sensations you get when you hit it.
Regardless of how it got its name, no one could blame you for wearing elbow pads all the time in an attempt to try & avoid the totally-not-hilarious pain that comes from hitting your “funny bone”. The only thing funny, at that point, would be the looks you might get from folks.
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