Does Cracking Your Knuckles Really Give You Arthritis?

Jaysin Trevino, Flickr // CC BY 2.0
Jaysin Trevino, Flickr // CC BY 2.0

You’ve heard it before. You’re in a quiet room in among a gathering of people, and then—POP!—a little cracking noise rings out, followed by another, and another, and another. For some, cracking knuckles is a habit, while for others that little pop brings relief. And it's not just reserved for tough guys before they beat people up: Between 25 and 54 percent of all people crack their knuckles multiple times a day. But is the old wives’ tale true? Are these knuckle-crackers more likely to hurt their hands and gradually develop arthritis as they get older? 

In short, nope! Despite the rumor that kids constantly hear, it turns out there is no scientific correlation between cracking your knuckles and developing arthritis in your joints, which is when one or more of the points where your bones meet develop inflammation. 

When you crack your knuckles, you're actually doing more bursting than cracking. The popping noise you hear is caused by small bubbles bursting in your synovial fluid, a yolk-like substance that lubricates the areas between bones and reduces friction for ease of movement.

Here's how it works: When you make the motion to crack your knuckles—either by stretching your fingers or bending them backwards—you expand the joint. This causes the pressure between the joint  to decrease, as well as the ligaments that connect the bones and the joint capsule that holds all of it together. That depressurization causes gasses like carbon dioxide, nitrogen, and oxygen that are dissolved in the synovial fluid to form into little bubbles that rush into the empty space. As the joints settle back into place, the fluid also returns to its rightful place and pops those little bubbles, causing that recognizable cracking sound. 

The sensation of cracking your fingers feels good because the stretching of the joint also stimulates nerve endings found along the fingers; joints can’t be cracked more than once within 15 minutes to a half hour, which is about how long it takes for those gasses to dissolve back into your synovial fluid.

Among the scientific studies conducted to prove that there is no correlation between cracking your knuckles and osteoarthritis, one published in the Journal of the American Board of Family Medicine in 2010 found that, among a group of 215 participants between the ages of 50 and 89, arthritis was prevalent in about 18 percent of the people who crack their knuckles and in 21.5 percent who don't, making any correlation inconclusive. Probably the most entertaining study on the subject is by a Dr. Donald Unger who, inspired by his mother’s warnings as a child about getting arthritis by constantly cracking his knuckles, spent more than 60 years cracking only the knuckles on his left hand at least twice a day (in this case, the right hand served as his control). His finding, published in 1998 in a journal called Arthritis & Rheumatism, found there was no discernible sign of arthritis in his left hand as opposed to his right.

So don’t listen to what mom says, everybody—feel free to crack away!

12 Perfectly Spooky Halloween Decorations Under $25

Amazon/shopDisney
Amazon/shopDisney

Halloween is right around the corner—which means it’s officially time to bring out the jack-o'-lanterns, watch scary movies, buy your costume(s), and hang up your festive decorations. Although there are thousands of decorations to choose from, you don’t have to blow your budget while decking out your house or apartment in honor of the spooky season this year. With a little guidance, you'll find plenty of ways to create the perfect ambiance at home without going for broke. (And best of all, you can put the money you saved toward extra Halloween candy to stash away.)

From giant spiders to hanging ghosts and lawn decorations, here are a few of our favorite props under $25.

1. Halloween Pillow Covers (4-Pack); $17

ZJHAI/Amazon

These adorable Halloween-themed pillowcases make the perfect accessory for any couch, sofa, or mattress. Made with thick linen fabric, these are durable, sturdy, and designed to last for seasons to come. (Tip: To prevent the zipper from breaking, fold the pillow in half before inserting.)

Buy it: Amazon

2. Black Lace Spiderweb Fireplace Mantle; $12

Aerwo/Amazon

This versatile spiderweb prop is made with 100-percent polyester, and its knit lace spiderweb pattern adds a spooky touch to any home. Display it on your doorway, across your fireplace mantel, or atop your table. (It also makes a great backdrop for Halloween photo ops.)

Buy it: Amazon

3. Statement Halloween Signs; $16

Dazonge/Amazon

These festive, statement-making banners come pre-assembled, making them incredibly easy to install. They’re also weather-resistant and washable for both outdoor and indoor use. Use tape, push-pins, or weights to prevent the signs from blowing away.

Buy it: Amazon

4. Jack Skellington and Sally Plush Dolls; $23 (Each)

Disney

Celebrate your favorite holiday with a pair of adorable Jack Skellington and Sally plush dolls from Tim Burton’s The Nightmare Before Christmas. Jack stands at 28 inches tall, while Sally is a bit shorter at 21 inches. Set them up on your sofa or against the window sill for all to see.

Buy them: Disney Shop (Jack and Sally)

5. Halloween Zombie Groundbreaker; $22

Joyin/Amazon

This spooktacular zombie lawn decoration is sure to scare all of your friends, family, and neighbors alike. Made with a combination of latex, plastic, and fabric, this durable Halloween prop is sure to last for years to come.

Buy it: Amazon

6. Hanging Ghost Decoration; $14

Moon Boat/Amazon

Drape this handmade, 14-foot-long hanging ghost decoration over your porch, doorway, or window. You can also hang it outdoors over a tree or a (very tall) bush. And, since it comes pre-assembled, you won’t have to waste time constructing it yourself.

Buy it: Amazon

7. Two-Piece Hanging Ghost Set; $17

GeeFuun/Amazon

This pair of ghosts adds a whimsical touch to any home. While they’re not “scary,” per se, they certainly are adorable. Display them in your front yard, on your porch, on a lamppost, or a tree. To hang, simply tie the ribbons and bend the wires, arms, and tails.

Buy it: Amazon

8. Pumpkin String Lights; $19

Eurus Home/Amazon

Not only are these solar-powered, 33-foot-long LED string lights good for the environment, they’re also incredibly easy to install (no long, tangly power cable chords necessary). Since they’re waterproof, you can use them both indoors and outdoors. Choose from eight different light settings, including twinkling, flashing, fading, and more.

Buy it: Amazon

9. Inflatable Ghost; $22

Joiedomi/Amazon

This adorable inflatable ghost (which dons a cute-as-can-be wizard hat!) features built-in LED lights and sandbags to help it stay sturdy. It also comes complete with a plug, extended cords, ground stakes, and fastened ropes. Simply plug it in and watch it magically inflate within just a few minutes.

Buy it: Amazon

10. Graveyard Tombstones; $17

meiguisha/Amazon

Turn your front lawn into a graveyard with this six-piece set. Each tombstone is made with foam and designed to add a touch of spookiness to your space. To install, insert one holder into the bottom of the tombstone, and one into the soil. You can use these indoors, as well.

Buy it: Amazon

11. 10-Piece Skeleton Set; $24

Fun Little Toys/Amazon

This skeleton set includes a skull, hands and arms, and legs and feet—plus five stakes to hold everything in place. Each “bone” and “joint” is flexible, allowing you to prop the skeleton into different frighteningly fun poses. Simply place the stakes into the bone socket and turn clockwise.

Buy it: Amazon

12. Outdoor Spider Web; $18

amenon/Amazon

This giant, ultra-stretchy spider web spans a whopping 23 feet. It also includes a 30-inch black spider, 20 pieces of fake spiders, one hook, and one nail. Its thick polyester rope—combined with the sturdy stakes—allows the spider web to stay in place all season long. Place the hook on a wall or tree, and expand the web using the stakes.

Buy it: Amazon

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Why Do We Say 'Trick or Treat' on Halloween?

"Give us candy, or else!"
"Give us candy, or else!"
kali9/iStock via Getty Images

Each Halloween, hordes of costumed kids trudge from door to door exclaiming the same phrase at each stop: “Trick or treat!” It’s really a treat-only affair, since adults always shell out candy and children rarely have tricks up their sleeves (except perhaps for those dressed as magicians). In other words, they may as well save half a breath and simply shout “Treat!”

So, where did the term come from?

Halloween Hijinks

Halloween wasn’t always about cosplay and chocolate bars. During the 19th century, Irish and Scottish children celebrated the holiday by wreaking (mostly harmless) havoc on their neighbors—jamming hot cabbage into a keyhole to stink up someone’s house, frightening passersby with turnips carved to look ghoulish, etc.

According to History.com, kids didn’t give up that annual mischief when they immigrated to the U.S., and Americans happily co-opted the tradition. Toppled outhouses and trampled vegetable gardens soon gave way to more violent hijinks—like the time a Kansas woman almost died in a car crash after kids rubbed candle wax on streetcar tracks, for example—and these pranks escalated during the Great Depression.

Almost as terrifying as a turnip.London Stereoscopic Company/Hulton Archive/Getty Images

In short, tricks were a huge part of Halloween throughout the early 20th century. So, too, were treats. For All Souls’ Day in the Middle Ages, people went door-to-door offering prayers for the dead in exchange for food or money, a tradition known as souling. A similar custom from 19th-century Scotland, called guising, entailed exchanging jokes or songs for goodies. While it’s not proven that modern treat-begging is directly derived from either souling or guising, the practice of visiting your neighbors for an edible handout around Halloween has existed in some form or another for centuries.

Canada Coins a Catchphrase

With tricks and treats on everyone’s minds come October, it was only a matter of time before someone combined them into a single catchphrase. Based on the earliest known written references to trick or treat, this may have happened in Canada during the 1920s. As Merriam-Webster reports, a Saskatchewan newspaper first mentioned the words together in an article from 1923. “Hallowe’en passed off very quietly here,” it read. "'Treats' not 'tricks' were the order of the evening." By 1927, young trick-or-treaters had adopted the phrase themselves.

"Hallowe’en provided an opportunity for real strenuous fun," Alberta’s Lethbridge Herald reported in 1927. "No real damage was done except to the temper of some who had to hunt for wagon wheels, gates, wagons, barrels, etc., much of which decorated the front street. The youthful tormentors were at back door and front demanding edible plunder by the word 'trick or treat,' to which the inmates gladly responded and sent the robbers away rejoicing."

The phrase appeared in Michigan’s Bay City Times the following year, describing how children uttered "the fatal ultimatum 'Tricks or treats!'" to blackmail their neighbors into handing out sweets.

Donald Duck's Endorsement

Sugar rationing brought trick-or-treating to a temporary halt during World War II, but the tradition (and the phrase itself) had gained popularity once again by the early 1950s—with some help from candy companies and a few beloved pop culture characters. Charles Schulz depicted the Peanuts gang cavorting around town in costume for a Halloween comic strip in 1951; and Huey, Dewey, and Louie got to go trick-or-treating in a 1952 Donald Duck cartoon titled Trick or Treat.

Fortunately, the treat part of the phrase has thoroughly overtaken the trick part. But if you stuff rank cabbage in your neighbor’s keyhole this Halloween, we won’t tell.

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