The human elbow is a hinge-joint system made up of three bones: The humerus, the radius and the ulna. The humerus starts at the shoulder socket, while the radius comes from the thumb-area of the wrist and the ulna from the little finger side. Those three bones—connected by numerous tendons and ligaments—create the pivotal hinge that allows you to lift weights, hold books and put together laborious flatpack furniture. Yay!
No Laughing Matter
The weird, painful sensation you get when you say you “hit your funny bone” is actually the result of your ulnar nerve—which is connected to your fourth and fifth fingers—hitting your humerus (and “humerus” sounds like “humourous,” hence, “funny bone”).
You can get “tennis elbow”—otherwise known as lateral epicondylitis—without playing tennis: It’s caused by repetitive bending and flexing of the elbow, causing the tendons that connect the bone to the elbow itself to degenerate. Unfortunately, if you do contract it doing your sport of choice, the only way to heal it is to stop doing said sport until it feels 100 percent again. In the U.S., so many children were getting elbow and wrist injuries via trampolines that the American Board of Pediatrics felt the need to issue an official warning against recreational trampoline use.
Read It and Weep
It’s not just strenuous activity that can damage your elbow—even hoisting the latest celebrity bestseller into the correct position in the early hours can take its toll. Ulnar neuritis, or inflammation of the ulnar nerve, can lead to continued numbness in the fingers and parts of the hand. If you’re totally engrossed in the narrative and don’t want to put your book down, experts recommend frequently changing position to avoid these complications