What is the Funny Bone, and Why Does Hitting It Hurt So Much?

iStock / ljubaphoto
iStock / ljubaphoto

The "funny bone" is neither funny (when you whack it on the edge of a piece of furniture), nor a bone (whether you whack it or not). Where'd the name come from, and why is it so painful?

What it is

The funny bone is actually the ulnar nerve, a nerve that runs from the neck all the way to the hand, where it innervates several muscles in the hand and forearm and ends in two branches that innervate the pinkie and half of the ring finger.

Why it hurts

For most of its length, the ulnar nerve is protected, like rest of the body's nerves, by bones, muscles and/or ligaments. As the nerve passes the elbow, though, it runs through a channel called the cubital tunnel, and here it's protected only by skin and fat, making it vulnerable to bumps. When you hit your funny bone, you're actually hitting the nerve against bone and compressing it. The result is an exhilarating cocktail of numbness, tingling and pain that shoots through the areas where the nerve does its work: down the forearm and hand and into the ring and pinky fingers.

Playing the name game

There are two camps in the debate over how the ulnar nerve got be known as the funny bone. One side says that it's an anatomical pun, because the nerve runs along the humerus, which sounds like "humorous." (Get it?) The other side claims that the nerve got its nickname because of the funny (as in odd) feeling you experience after you hit it.

Things could be worse

When you hit your funny bone, it seems like the worst thing in the world, but imagine experiencing chronic irritation there, like someone banging on your funny bone day and night. It sounds like a method of torture you'd dream up in a revenge fantasy, but it's a very real problem called cubital tunnel syndrome.

Cubital tunnel syndrome occurs when the ulnar nerve is obstructed during its trip along the elbow and gets pinched or squeezed, usually from sleeping with the arm folded up. The result is the same as a quick whack to the funny bone: numbness, pain and a tingling sensation, but it lasts a bit longer. Over time, progressive irritation of the nerve causes the numbness to settle in and stay. Muscle weakness in the forearm and hand can also set in, and the pinkie and ring finger can curl up in a position called the "ulnar claw." The condition can usually be helped with elbow splinting and the correction of aggravating postures, hand therapy or, in extreme cases, surgery that provides more space for the nerve and reduces the amount of pressure on it.

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

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30 Pungent Facts About Farts

This man is clearly not trying to hide the fact he just passed gas.
This man is clearly not trying to hide the fact he just passed gas.
BrilliantEye/iStock via Getty Images

Whether you openly admit it or desperately try to hide it, it’s an undeniable fact that every living and breathing human being farts. And while passing what you thought was going to be silent gas only to be wrong in certain situations can definitely be embarrassing, there’s something undeniably humorous about flatulence—no matter your age.

If you do love a good fart joke, you’re in good company. The very first recorded joke, which was written by the Sumerians and dates all the way back to 1900 BCE, was about—you guessed it—breaking wind. And some of the world's great thinkers, from William Shakespeare to J.D. Salinger, have slipped a fart joke (or 10) into their work.

In this episode of The List Show, we're sniffing out 30 fascinating facts about farts—from why humans expel gas to how often the average adult squeezes the cheese. You can watch the full episode below.

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