It usually happens without notice or warning. You are just moving along, minding your own business when, POW! you hit what everyone crazily refers to as your "funny bone."
At this point, I am confident you are not laughing. I am pretty sure you know the feeling about which I speak. You get that sudden tap on just the right spot behind your elbow, and before you know it, you have a mix of pain and a tingling sensation shooting straight down your forearm.
Interestingly enough, your “funny bone” is not even a bone at all. According to Dr. Jonathan Cluett, practicing orthopedic surgeon in Massachusetts and expert on About.com, what you are experiencing when this part of your elbow is hit is a reaction from the ulnar nerve, which passes around the back of the elbow. This nerve sits atop the hard elbow, and without a lot of fatty tissue surrounding it, you are bound to strike it inadvertently from time to time. (What a place to put a nerve, right? The nerve!)
To be more exact, the ulnar nerve is one of the three main nerves in the arm. It starts at the collarbone and leads down the inside of your upper arm. From there, it extends behind the inside of the elbow. It is at this spot that you can feel the nerve just beneath your skin. From there, the ulnar nerve moves under muscles located on your inner forearm and leads its way to the side of your palm that boasts the little finger. Now you know why a blow to your funny bone can make your pinkie feel a bit weird.
According to the American Academy of Orthopedic Surgeons (AAOS) at www.orthoinfo.aaos.org, sometimes the ulnar nerve can become compressed, causing discomfort or pain. Some contributing factors to this include a prior fracture to the elbow, bone spurs, cysts, or any swelling surrounding the elbow joint. (That is clearly taking that “funny bone” feeling to a whole new level, isn’t it?)
How do you know if your “funny bone” (or ulnar nerve) might be compressed? The experts at the AAOS indicate if you have tingling sensations similar to those when your foot falls asleep in your ring finger or pinkie finger when your elbow is bent, that could signal a possible compressed ulnar nerve.