Why does it hurt so much to hit your funny bone?

MINNEAPOLIS — The funny bone is anything but funny. So why does it hurt so bad when it gets hit? It turns out there's a "humerus" answer.

WCCO spoke with Dr. L. Pearce McCarty III, who specializes in elbows.

"Well, a lot of people already know the funny bone is not a bone. It's a nerve," McCarty said. "Right between those bony points runs the ulnar nerve, that's the funny bone."

It's a nerve cleverly named for its proximity to the humerus bone.

"So the nerves are super close together in this intersection which is an elbow. It's all right there," he said. "So nerves are like electric cables. If you smash a nerve, it discharges its energy."  

He says there's an activation, like a shock. There are three nerves in the elbow, with the ulnar nerve located directly beneath the skin's surface, making it extra sensitive.

McCarty says if funny bone pain lasts a while or you experience numbness in your fingers, see your doctor.

But 99% of the time, the pain doesn't last much longer than a curse word.