So the ulnar, median, and radial nerves are three of the many branches of the Brachial Plexus. They start from the arm, then extend all the way to the hands and innervate the areas I have indicated.
The ulnar nerve is otherwise known as the “funny bone.” It feels funny because when the ulnar nerve comes around the elbow, it is not protected by any layer of muscle. So when you hit your elbow, you hit your ulnar nerve easily. But don’t hit too hard, or else an injury to your ulnar nerve will make your hand look like this, also known as “claw hand”! Cubital Tunnel Syndrome occurs at old age with wear and tear of the Ulnar nerve, and your hand will look like that too!
If you injure your median nerve, your hand will look like this, and people might think you are the pope and you are going to bless them! It is called the Hand of Benediction. Carpal Tunnel syndrome occurs when you wear and tear your median nerve, by prolonged activities that compress your wrist where the nerve runs through.
If you fracture the middle part of your arm (where the radial nerve runs through the radial groove of the humerus), you can injure your radial nerve. Your wrist will drop and look like this, because the radial nerve, of course, innervates the wrist!
So in conclusion, three lessons to learn in life:
- don’t hit your funny bone too hard
- don’t break your arm, and surely,
- give your wrist a rest!