10 Things You Might Not Know About the Elbow

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The human body is an amazing thing. For each one of us, it's the most intimate object we know. And yet most of us don't know enough about it: its features, functions, quirks, and mysteries. Our series The Body explores human anatomy, part by part. Think of it as a mini digital encyclopedia with a dose of wow.

Unless you bang your funny bone or regularly play tennis, it's unlikely you spend a lot of time thinking about your elbow. But without this crucial joint, many daily activities would be impossible, explains Anand Murthi, attending orthopedic surgeon and chief of shoulder and elbow surgery at MedStar Union Memorial Hospital, in Baltimore, Maryland.

1. THE ELBOW IS MORE COMPLEX THAN IT MAY SEEM.

The elbow may seem small, but it requires three bones to make its simple hinging action possible. The humerus is a long bone that runs from the shoulder socket to the radius and ulna. (And yes, there's a school of thought that believes your "funny bone"—actually your ulnar nerve—is named as a play on the word humorous.) The radius is one of the two forearm bones, running down from the elbow to the thumb side of the wrist. Lastly, the ulna stretches away from the pinkie side of the wrist. Thanks to those three bones, your arm can hinge—making it possible to do a bicep curl, lift a bag, or rotate your hand.

2. IT'S ALL HELD TOGETHER BY A KEY LIGAMENT, AS INJURED ATHLETES KNOW WELL …

The bones of the elbow are connected by numerous tendons and ligaments, including the ulnar collateral ligament, a fibrous tissue that connects the humerus to the forearm bones. This tendon is both important and vulnerable. When it ruptures or tears, you feel severe pain and can sometimes even see bruising on the inside of your arm. It's a surprisingly common sports injury, plaguing players of baseball, football, ice hockey, and golf. The other major ligament in the joint is called the radial collateral ligament. Located on the outside of the elbow, it prevents excessive extension of the elbow, and is less prone to injury.

3. … BUT THAT'S NOT THE ONLY VULNERABLE PART OF YOUR ELBOW.

At the lower end of the humerus are two rounded protrusions called epicondyles, which flare out from the bone. This is where muscles attach. The upper end of the ulna also has two protrusions, called the olecranon—which forms the pointy part of the elbow—and the caronoid process, a projection from the front of the ulna. Bone fractures, especially in children, often occur at these epicondyles, and are the most common short-term injuries of the elbow. Certain kinds of arthritis, especially in older patients with osteoarthritis, can also cause such severe degeneration here that an elbow replacement is necessary. (Since bones become more brittle as we age, it's wise to take steps to prevent falling or stumbling, as elbows are among the most likely casualties.)

4. TRAMPOLINES ARE COMMON ELBOW-BREAKERS.

Children love the thrill of a jump on the trampoline, but Barbara Bergin, an orthopedic surgeon in Austin, Texas, tells Mental Floss that she sees numerous fractures around the elbow in kids from doing just that. It's so common to break elbows and wrists this way, the American Board of Pediatrics warns against trampolines.

5. TWENTY-THREE MUSCLES GIVE YOUR ELBOW STABILITY AND FLEXIBILITY.

But the major muscles involved in bending your arm are the triceps—on the back of your arm—and biceps, on the front of your arm. Your many smaller flexor and extensor muscles allow you to move your wrists and fingers and rotate your forearm.

6. YOU DON'T HAVE TO PLAY TENNIS TO GET TENNIS ELBOW.

One of the most common conditions of the elbow is called "tennis elbow"—or lateral epicondylitis. Tennis players are prone to it, but it can be caused by any repetitive bending and flexing of the elbow, says Bergin. It's a painful degeneration of the tendons that attach to the bone on the outside of the elbow. It's so common, she says, "I probably see tennis elbow every day in my office." If the condition should strike you, Bergin says, "It's critical to stop doing whatever hurts. It will not get better if you continue to participate in whatever activity is causing pain." Full and total healing is required before you can return to the activities that gave you the condition in the first place.

7. IF IT GETS BAD ENOUGH, YOU MAY NEED "TOMMY JOHN" SURGERY.

When major league pitcher Tommy John injured his ulnar collateral ligament in 1974, his doctor opted to try a unique surgery to replace the deteriorated ligament with a tendon from somewhere else. Though the surgery can require a full year's recovery time—in Tommy John's case, it was nearly two and a half years and two surgeries—it's since become a time-tested method to repair this damaged ligament. Murthi tells Mental Floss, "New research on repairing the medial collateral ligament (versus reconstructing it) may lead to earlier recovery for Tommy John surgery. Also new treatments for articular cartilage damage, ligament reconstruction, and joint sparing techniques are evolving."

8. BUT IT'S HARD TO OPERATE ON YOUR ELBOW.

The elbow's close proximity to important blood vessels and nerves in your hand and arm make it a challenge to perform surgery on, Murthi says: "Careful, precise surgery is required to provide a good outcome. Often, rehabilitation with a skilled therapist is crucial to a good recovery." Currently, many operations are performed arthroscopically, so that surgeons can see all the various components as they make delicate maneuvers.

9. IF YOU HAVE TO GET AN AMPUTATION, HOPE FOR ONE BELOW THE ELBOW.

Should you have the misfortune of losing part of an arm, it's better to lose the parts below the elbow, Bergin says. This helps you maintain a range of motion and allows you to better manipulate a prosthesis. Fortunately, upper extremity amputations are rare and almost always result from accidents, as compared to lower arm amputations, which are often caused by some form of vascular disease.

10. EVEN JUST READING A BOOK CAN CAUSE AN ELBOW CONDITION.

While you may be tempted to read that latest hefty bestseller late into the night, if you're keeping your elbows bent in a sitting position for too long, you can get a case of ulnar neuritis, inflammation of the ulnar nerve—which can lead to numbness or weakness of the fingers and hand. Bergin warns, "It's much more common now than it used to be because we sit around for hours at a time on our phones." If you experience a "little tingly feeling in the pinky and fourth finger," she says, you've probably got a case. Her recommendation is to take as many breaks with your arms straight out as you can. Switch to a kindle or laptop that you can prop up to read at night. Be conscious of your ergonomics when you drive, type, and use your electronics.

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

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30 Pungent Facts About Farts

This man is clearly not trying to hide the fact he just passed gas.
This man is clearly not trying to hide the fact he just passed gas.
BrilliantEye/iStock via Getty Images

Whether you openly admit it or desperately try to hide it, it’s an undeniable fact that every living and breathing human being farts. And while passing what you thought was going to be silent gas only to be wrong in certain situations can definitely be embarrassing, there’s something undeniably humorous about flatulence—no matter your age.

If you do love a good fart joke, you’re in good company. The very first recorded joke, which was written by the Sumerians and dates all the way back to 1900 BCE, was about—you guessed it—breaking wind. And some of the world's great thinkers, from William Shakespeare to J.D. Salinger, have slipped a fart joke (or 10) into their work.

In this episode of The List Show, we're sniffing out 30 fascinating facts about farts—from why humans expel gas to how often the average adult squeezes the cheese. You can watch the full episode below.

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