How come your funny bone is called your funny bone?
How come your funny bone is called your funny bone? asks Noah Kennedy White.
If you’ve ever hit your funny bone, you know that the only amusement comes from the faces, gestures, and sounds you make as you grab your elbow and dance around the room. The vibrating pain, extending to your fingers, seems to start in the knobby bone on the inner elbow. Actually, the bone is an innocent bystander; it’s a nearby nerve that’s causing all the excruciating commotion.
It should be called the Funny Nerve, but its official name is the ulnar nerve (after the ulna bone in the forearm). Stretching from neck to hand, the ulnar nerve sends impulses back and forth from the spine.
The pain from hitting the ulnar nerve is no laughing matter. Smaller nerves running through the skin allow us to sense heat and cold, or to feel the prick of a thorn before it pierces the skin. These nerves are relatively unprotected, so that we can perceive the world around us. But the ulnar nerve is a big nerve. Its main function is to control muscles in the forearm and hand, as well as enabling our pinky and ring fingers to feel sensations.
Other large nerves are protected by bone and fat. But the ulnar nerve is almost completely exposed. The ulnar nerve runs in a bony groove (the “cubital tunnel”) through the elbow, where all that stands between desktop and nerve is an thin layer of fat and skin.
Bump your inner elbow, and this large, exquisitely sensitive nerve is slammed between your solid bone and, say, the top of your desk. The result is a searing, tingling, electric pain that starts in your elbow, shoots down your arm, and ends in the fourth and fifth fingers of your hand. Youch.
It’s easy to see why people thought the elbow bone was the painful culprit, instead of a nerve no one could see or feel. But hitting your ulnar nerve is about as funny as a toothache. So what’s the amusing part? Some say the spot is called the funny bone because the ulnar nerve runs along the “humerus” bone in the upper arm. (Get it? Humorous?) But the real reason is probably because the feeling is so odd-unlike the pain from a bump anywhere else on the body. “Funny,” in this case, probably just means “peculiar.”
While the pain from hitting your funny bone only lasts a few seconds, the ulnar nerve can become irritated from simple daily activities. The telltale signs: burning pain in the elbow, and tingling and numbness in the pinky and ring fingers, and in the outside of the hand. Known as cubital tunnel syndrome, the symptoms are a result of the nerve being stretched and held against the bony bump of the elbow for long periods. Sleeping with your arm bent, holding a phone to your ear for hours, and leaning on your elbow can all annoy the ulnar nerve.
For more on the ulnar nerve and cubital tunnel syndrome, visit
www.muschealth.com/gs/HealthTopic.aspx?action=showpage&pageid=P00908.
