A patient walked in to clinic today and said: “I get the strangest tingling in my hand when I reach into the back seat of my car. It is just in my palm, my thumb, and my pointer finger…it feels SOOO strange!”
Hmmm, ok. Want to give that a try at home? Stretch both your arms straight out:
Then extend them back as far as you can behind you, even stretch your fingers waaaay baaaaack and then turn your palms up.
Feel a stretchy tingling feeling?
If not, you’ve got some nice flexibility in your nerves. If so, don’t panic…you’ve just stretched your Median N. a little bit.
I instantly geek out when I get to draw fun anatomy pictures for my patients, indeed some of my regular patients are getting used to the excited look that comes over my face when they ask an anatomy question! The sensory innervation of the wrist and hand is pretty cool because of the interesting way it breaks up the hand. There are three nerves that block out the hand in the loveliest way, Piet Mondrian couldn’t have done better. Check it out:
Look at that ring finger! Three flipping nerves innervate that sucker, which makes it a great tool for detecting specific nerve damage. Sometimes people present with loss of sensation on just one side of their ring finger. If you know your hand anatomy, you’ll look like Sherlock Holmes!
In other awesome, hand nerve news…. When you “bump your funny bone” you are hitting your Ulnar N. that runs very superficially by your elbow. Next time you bump it, instead of inventing some new four letter words, take a breath and see if the pain / tingling is on the outside (yellow in the painting) bit of your hand. Cool eh?