Palmaris Longus: The Muscle You Might Not Have

Palmaris Longus: The Muscle You Might Not Have | Corporis

Рет қаралды 37,322

6 жыл бұрын

About 15% of humans don't have a muscle in their forearms called the Palmaris Longus. As a muscle, it's pretty useless. But still, why do some people have it while others don't?
What mechanism is behind the whole thing? In this video, I explain why there's still variation among different bodies and why this obsolete muscle exists still.
☠️NONE OF THE INFORMATION IN THIS VIDEO SHOULD BE USED AS MEDICAL ADVICE OR OPINION. IT IS FOR GENERAL EDUCATION AND ENTERTAINMENT☠️
🔗 L I N K S 🔗
📱Instagram: / patkellyteaches
🐦Twitter: / patkellyteaches
💰Patreon: / corporis
📽 O T H E R V I D E O S 📽
⚰️Medical History playlist: • Playlist
🔬Anatomy Basics playlist: • Basics of Anatomy
💪Kinesiology and Biomechanics playlist: • 💪Musculoskeletal, Biom...
📜 S O U R C E S 📜
Grip Strength Unaffected By PL Removal (2005)
journals.sagepub.com/doi/10.10...
Heredity of PL (2013)
jms.org.br/PDF/v30n4a08.pdf
Palmaris Longus comparison (2014)
www.hindawi.com/journals/bmri...
The changing upper extremity (2014)
www.ncbi.nlm.nih.gov/pmc/arti...
Percentages of PL (2016)
www.ncbi.nlm.nih.gov/pmc/arti...
www.flickr.com/photos/interne...
Lemur Hand By Alex Dunkel (Maky) - Own work, CC BY-SA 3.0, commons.wikimedia.org/w/index...
Chimpanzee By © Hans Hillewaert /, CC BY-SA 3.0, commons.wikimedia.org/w/index...
en.wikipedia.org/wiki/Ring-ta...
en.wikipedia.org/wiki/Ring-ta...
• Thompson's Test for Pa...
💊A B O U T 💊
Hi, I’m Patrick. I’m a freelance science writer based in the San Francisco Bay Area. I hold a bachelor’s degree in Athletic Training and a master’s in clinical exercise physiology. I used to work in the clinical setting as a certified athletic trainer, physical therapy aide, and a certified strength and conditioning specialist. After working in the clinical setting, I went back to school and became a teacher. The goal of my content is to help normal people, not just pre-med students, learn about the human body. That might mean explaining a topic from an anatomy class or exploring a topic from medical history.
💻 C O N T A C T 💻
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patkellyteaches [at] gmail.com
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Пікірлер: 181

@lizabine 6 жыл бұрын

You should rename your channel PK Prompt

@alial_hassanal_khashashneh3728 4 жыл бұрын

I can name a bunch of organs that were thought to be useless but then they were proven to be of great importance. As for the tailbone "coccyx" is responsible of binding muscle strings and ligaments of the pelvis and support the body weight when setting. Not knowing the function of an organ doesn't mean it is no necessary

@wylantern 4 жыл бұрын

I think there's also a muscle that has degraded function in the leg preventing a lot of people from planting their feet fully while squatting, but I might be wrong.

@Corporis 4 жыл бұрын

Good question! I mentioned it somewhere in the video, but when I was researching, I heard that a small muscle in the elbow (the anconeus epitrochlearis) once had a greater function in humans. BUT, since we don't weight-bear on our arms, we lost it. As far as some muscle with degraded function in the legs, I'm assuming you're talking about the tibialis posterior, but that'd be the result of wearing shoes if anything, not an evolutionary adaptation.

@joshua7551 3 жыл бұрын

Makes me wonder why there is an apparent link between full plant squatting and northern european peoples. Time to find a new youtube rabbit hole to jump down.

@allahbless2278 Жыл бұрын

@@Corporis He's being sarcastic about the people with bad form mate

@billyjoeness6546 5 жыл бұрын

I dont have it, voila Iam a superior evolved being

@shaneomac5512 5 жыл бұрын

Brother

@phantomx3902 4 жыл бұрын

lmao

@petermikus2363 3 жыл бұрын

I dont too

@simpinatorthedestroyerofsi6056 3 жыл бұрын

Bruh you are missing a muscle, more like genetic inferior😎

@ch0colat_831 3 жыл бұрын

Same here

@vlad5892 3 жыл бұрын

My left hand doesnt have it, but my right one does

@aravindgtr 3 жыл бұрын

Ya it's possible

@dogwater8658 3 жыл бұрын

Same

@josephlyonsjr3886 3 жыл бұрын

Does the usage in your hands feel any different

@juicezzz992 3 жыл бұрын

My left has it, right doesnt

@juicezzz992 3 жыл бұрын

@@josephlyonsjr3886 when I go up to a tree it feels more right to put the left hand on the tree, not even kidding

@miaduplessis4646 4 жыл бұрын

A very well put-together video! We used our video on our physiotherapy Facebook page to educate our patients. They loved it!

@Corporis 4 жыл бұрын

Aww, thanks for the kind words. I hope they got something worthwhile out of my ol' video.

@mikemulryan 2 жыл бұрын

Mother has both, father has none. I have both! Pretty interesting how a whole muscle, albeit not really needed can still appear in a person when about half their genome comes from someone without the muscle.

@anonymoususer477 3 жыл бұрын

You need more hype I can tell you worked hard on this video :)

@KevinLuWX 2 жыл бұрын

Where did you get that 3D view of the arm muscle and tendons?

@libera317 2 жыл бұрын

I have it only in left hand, I've always preferred this hand when it comes to grip strength. Maybe it has some benefits after all?

@judith8161 4 жыл бұрын

I think I don't have it in my left hand, which is kinda funny because I'm left-handed. I'm now gonna use this as an excuse whenever I fail to open a bottle or a jar :D.

@7_y1ar 3 жыл бұрын

its cool that i have it on my left hand and im right handed

@those-who-live-in-death 2 жыл бұрын

Same as u, left handed and only have in right arm

@arou_nation01 Жыл бұрын

Appreciate the info. Just had my palmaris removed n place in my middle finger still won’t be able to ball my fist up, but better days to come 🤝💯

@AvatarPrimus 6 ай бұрын

Interesting video, I don´t have that muscle in any of my forearms. Greetings from Mexico.

@maureenkelly738 6 жыл бұрын

I’ve heard from other YTbers that VidCon was a bit disorganized. Hope you had a good Rhine nonetheless.

@offendersatv3566 4 жыл бұрын

It's been patched

@Snippiii 4 жыл бұрын

😆

@Nateda_ 4 жыл бұрын

wtf i want one and i dont have it edit: i found it thankgod

@eduardocruz3474 2 жыл бұрын

Hey is it normal to have on one hand and not have it on another ?

@7_y1ar 3 жыл бұрын

I have it on my left arm but none on my right and im right handed

@MartiGTR 2 жыл бұрын

Is it normal to have 1 in my right arm and 2 in my left?

@okestperson6016 4 жыл бұрын

I wonder if having that unilateral muscle in the elbow affects hand/arm dominance at all

@Corporis 3 жыл бұрын

I don't think it would. My research didn't say anything about that and I feel like that's one of those Fun Facts that science writers would love to sprinkle in

@rikobellic3567 Жыл бұрын

Have they even done a study comparing people with And without a palmaris longus? Maybe the grip strenght stays the same, but what about other functions? Its a muscle missing so it must have an effect if its missing

@Thicbladi 3 жыл бұрын

I just found out that I can move my elbow in all directings and I’m not twisting it or anything I’m holding my bicep to make sure my arm doesn’t twist and I can move my arm up down and left and right easily it’s kinda cool although only on my right arm

@LupeSunglass 3 жыл бұрын

May I see a video?

@valeriavagapova 5 жыл бұрын

This is so interesting! However, I'm not sure I'm understanding very well why this evolutionary process is still ongoing. From what I understand evolution is based purely on natural selection, meaning that offsprings with certain traits are more likely to survive and reproduce than others. I understand how the presence or absense of such a muscle affected survival in the past, but how does it affect us over the last few thousands of years and especially nowadays? I'm really curious to understand how this works!

@davidonfim2381 5 жыл бұрын

Evolution is just change (specificay, the change of allele frequencies in a population over time). It CAN be due to natural selection, which is what drives a lot of the more famous and visible changes throughout evolution, but it can also be due to other factors (such as genetic drift). When there is a LACK of selection for/against something, you can still therefore get change in the population. For example, complex things like muscles require that a lot of different processes occur properly. If the proper development of something (Palmaris longus muscle, for example) is not important, then you will get lots of different mutations in the population that alter it. Over time, you'll eventually get so many mutations building up that the development of the structure just doesn't happen... so the structure can go away completely. That, of course, assumes that the mutations don't affect other processes.

@fabioooh Жыл бұрын

Use it or lose it

@demoworks Жыл бұрын

I would like to know if people that are good drawing or using chopsticks have it but if those that don't are bad at those things

@UnoDickles2.0 Жыл бұрын

"Passively aggressively asking it to leave" Rolled me

@AleksPlaysMc 3 жыл бұрын

There was a study that I found showing more fatigue with those with a palmaris longus after playing piano for 15 minutes, than those who don’t. Any thoughts on this? Kinda making me wonder if I should get surgery to remove it since I play saxophone, and some studies claim it can be linked to carpal tunnel as well.

@TheRagingSound Жыл бұрын

How does our bodies decide what to keep and what not to keep?

@joeldoxtator9804 8 ай бұрын

I have two of these tendons on each side and can grip well over 500Lb. My upper back gives out before my grip does.

@inkflux. 4 жыл бұрын

Well I was born in 2004 mine is semi unilateral and the one that is prominent is just only slightly seen the other one is like a bump

@TheMitchellverse 6 жыл бұрын

Yeah babyyyyy :)

@perseusofmacedon6918 3 жыл бұрын

I have it in both arms

@stumpfightskills571 4 ай бұрын

If we use the muscle when we’re crawling, why don’t we use it when we’re doing dips or handstands? How about when we’re punching or pushing something?

@marcoloko 2 жыл бұрын

Is it possible to have only one? it seems like the tendon pops out in my left arm, but it doesn't on my right arm lol. Obs. i'm right handed if it matters

@Corporis 2 жыл бұрын

It is totally possible to only have one, none, or both!

@marcoloko 2 жыл бұрын

@@Corporis hey, thanks for responding, yeah i only saw that in the middle of the video lmao, shouldve commented later after finishing the video

@GoetzimRegen 3 жыл бұрын

So we should ask, are there pro climbers without it?

@kane00000 2 жыл бұрын

Wouldn't you rather want to know how many pro climbers have it verses the amount who do not? I think that would conclude more.

@justincameron9123 2 жыл бұрын

@@kane00000 those are literally the same exact thing. Thats like saying "I don't care what percent of the population is right handed, I want to know what percent is left handed"

@daskawicz 4 ай бұрын

Genetics in our family: I (f) don't have the muscle in either arm. My husband (m) has it in both arms. One of our children (m) lacks it in both arms. Another (m) lacks it in one arm and has it in the other. Our other two kids haven't gotten back with me yet on if they have it. We are all of almost 100% pure Caucasian ancestry.

@alexv3548 4 жыл бұрын

I just found out that I’m part of that 15%

@Corporis 4 жыл бұрын

Alex V proud of you son

@yahitajam7944 3 жыл бұрын

U have evolved and Evolutionary ahead of us remaining 85%.

@xboxisbetterthanplaystatio7082 3 жыл бұрын

i have it so does that mean im og

@ZH0NGLl 3 жыл бұрын

ayyee

@PresidentJeanAuguste 2 жыл бұрын

Same to me, 15% This made me curious since I was a child.

@simonruszczak5563 2 жыл бұрын

By race the absence of the palmaris longus is, 26.6 % in Turkish, 22.4% in Caucasian, 7.1 % in Native American, 4.8 % in Asian (17.2 % in Indian population), 3 % in Black.

@jellyandthecrewman1834 3 жыл бұрын

I have it on one side only what does that make me

@shwantheman1173 2 жыл бұрын

Help. what does it mean If I only have ONE

@xboxisbetterthanplaystatio7082 3 жыл бұрын

i didnt evolve

@MI-zt1wv 3 жыл бұрын

I'm still monkee 😢

@TheDonegan1 3 жыл бұрын

I have it on my left wrist but not my right

@christhehuman387 3 жыл бұрын

I have on both hands and now i wanna climb a tree-

@riichobamin7612 3 жыл бұрын

Whenever I clench my fist, I see two tendons pop up. Is that normal ?

@ArjanTigchelaar 3 жыл бұрын

Me too. I was confused as well.

@riichobamin7612 3 жыл бұрын

@@ArjanTigchelaar I am still confused 😂

@aleksanderosiowski3128 2 жыл бұрын

Yep the one despite palmaris longus is flexor carpi radialis, very strong and definitely not dissapearing muscle, main functiin is to flex the wrist and slightly pronate it

@riichobamin7612 2 жыл бұрын

@@aleksanderosiowski3128 thank you !

@justincameron9123 2 жыл бұрын

@@aleksanderosiowski3128 I have both muscles protruding 34/7 without flexing because I'm skinny

@asude1 3 жыл бұрын

I wish I had that muscle lol I don't have it on both arms and so does my mother

@chehystpewpur4754 2 жыл бұрын

your looking at the muscle/tendon wrong. thats why you dont get it. imagine holding your grip for aslong as you want without expending force. do we still ride in our mothers hair over long distances? or climb for safety? and need to stay up there for long periods? no but we still use our grip so its still useful. we still climb sometimes or ride bikes. drive cars. hold tools. its a good advantage if used properly. but we forget alot over the years.

@jasonpiper609 4 жыл бұрын

Um, I hate to break this to ya but the palmerus longus is NOT a spare tendon. Yes it's a sign of evolution, but it absolutely has many purposes. As someone who had a butchered tendon transfer surgery, this ruined my life and gave me the most painful disease known to man. This video is wrong on so many levels....

@Corporis 4 жыл бұрын

So sorry to hear you feel that way dude. Maybe I missed something, but what were the PL's other purposes?

@jasonpiper609 4 жыл бұрын

@@Corporis It's ok man. I had my life ruined by this so I get really animated because all I've heard are people who have never experienced this. Experience the best teacher. Here's the facts; it doesn't seem to serve a purpose but that's only for people who never had it, hence, never needed it and/or depended on it. For people who do have it, the other tendons, ligaments, etc, never knew anything other than having it. Once it's removed it over works every single piece of anatomy in the entire arm. As a drummer of 4 decades I am very aware of my hands/arms/digits, etc, and my drumming is ruined. Next I was WRACKED w/agonizing, bone crushing pain that became intolerable w/any movement. Then there's the 'pullies' that the surgeons manufacture and commonly fail (just like mine are doing now) which causes the most mind warping pain you could imagine as your fingers come off track and twist & contort. I lost any and all forearm strength and went from having ripped arms to not being able to open a bottle of pop/water. On too of all that I developed RSD, which turned into CRPS, which spread through my entire body and is currently killing me. Since my brother committed suicide & my dad just died I'll leavin' behind my disabled mom and our 4 pugs. I cant even open a ziplock bag, a bag of dog treats, etc. Its embarrassing and pathetic. Then of course all the poor pugs I would've saved who'll probably die since I was ABOUT to open my pug rescue. CRPS is the most painful disease known to man & has no cure & no treatments are covered by insurance. So my point is it's not 'just a spare tendon' because if ya add up the copious amounts of collateral damage, it's easy to see that almost everything has much deeper detail that needs to be examined before anyone can understand someone's situation or any topic like this. I really hope you guys NEVER, EVER have to experience this. I would've much rather have had my hand stuck in the contorted position & the severed tendons I presented with than havin' my hand & arm butchered & getting the most painful, relentless disease there is. Be very careful if you're working near glass or anything sharp....... PLEASE......

@jasonpiper609 4 жыл бұрын

And sorry about the typos but I can't feel my thumb or fingers....

@Valenm-ps2by 2 жыл бұрын

@@jasonpiper609 man, it’s been 2 years, are you alright?

@jasonpiper609 2 жыл бұрын

@@Valenm-ps2by hey there!! Thanx for askin' but I am screwed. The CRPS is relentless, my crushed, mangled spine is cavin' in & stabbing directly on my spinal cord, & need 5 or 6 surgeries that I ain't gettin'... I hope you're doin' ok...

@GabbyGrapist 2 жыл бұрын

I have it in one arm but not the other. Not sure what that means.

@robertsmelody2072 4 жыл бұрын

I don't have it either

@L3giT_Hax Жыл бұрын

I have a bilateral absence of this muscle and so does my mother, I'll update comment when I find out if my father lacks them aswell.

@joshtheflatearthjedi222 3 жыл бұрын

I don't have one in either arm and im pissed

@gabeisawesome879 Жыл бұрын

My pamerus longus tendons are HUGE and my forearm muscles are very small. I guess this means the most prominent visible feature of my wrists is something that is utterly useless lmao. That tracks with my general appearance as well, just not from a biology or evolutionary perspective lmao

@karma20241 Жыл бұрын

I wonder if anyone has questioned those without tendon to see if any are rh negative.

@elisereid5101 10 ай бұрын

Mine is absent in both arms and I'm Rh positive.

@kseniaeverton8089 8 ай бұрын

I enjoyed the comparative anatomy and evolutionary perspective! Thanks! One nitpicky comment: humans ARE apes, so maybe "humans and other apes" instead of "humans and apes". :)

@PresidentJeanAuguste 2 жыл бұрын

Woah, I didn't know I had these rare muscles. I'm still part of evolution

@Lechompski 3 жыл бұрын

I have one in my right arm only

@nihazq 3 жыл бұрын

Bruh mine sticks out so much. I have it in my left hand

@user-iu2gm7os7d 2 жыл бұрын

I have it on my right hand but not on my left hand

@skylerfall5886 2 жыл бұрын

I have a right one and no left one

@Joy-TheLazyCatLady 6 ай бұрын

I don't have that tendon. 😮

@Elijah-sf8ni 3 жыл бұрын

u can do both ePIX

@lolololo2965 Жыл бұрын

Its strange because only my left arm has it

@doll_face6188 Жыл бұрын

I think I need it because I do parkour

@sarahshon7035 3 жыл бұрын

I don’t have it. I am weirded out by this and Idk why.

@snowy9764 2 жыл бұрын

I have 3 of them..

@h20cozmic84 3 жыл бұрын

i have it and if you put your phone flashlight to it light traveles through it its cool

@user-kv8nu5hd1g 4 жыл бұрын

I have it on both arms

@Corporis 3 жыл бұрын

MVP!

@rafialfarizky6178 3 жыл бұрын

Same

@jimmiebentley6608 Жыл бұрын

Same.

@theneonking5455 2 жыл бұрын

I have one and I'm cracked at arm wrestling

@aravindgtr 3 жыл бұрын

I have on both hands

@mironmihai2641 4 жыл бұрын

So useless until proven necessary. Basically a spare tire!🤣

@Corporis 4 жыл бұрын

A spare tire leftover from a time when we needed it!

@tristanjoestar6756 4 жыл бұрын

Mine is so small tho

@alokmondal1151 3 ай бұрын

I have this muscle

@mosiden4656 Жыл бұрын

I can’t imagine losing that muscle. I need to climb trees with my homies 💪 😎

@melonlord4889 4 жыл бұрын

I only have it in one arm

@bunnyben5607 4 жыл бұрын

Left or right? I don't have it on the left myself.

@MuhammadAbdullah-fz9sm 3 жыл бұрын

I have it in one arm and not in the other

@andyymunar 3 жыл бұрын

So the muscle is that tendon? I have them both but one is much smaller in the hand that I use for writing

@jasonpiper609 2 жыл бұрын

Yes, it starts out as a tendon then becomes a muscle...

@tallpatc1578 11 ай бұрын

😊

@Snippiii 4 жыл бұрын

Count me in. Don't have it 😝

@Corporis 4 жыл бұрын

Welcome to the club

@jazzadieu 4 жыл бұрын

Why do I have 2 of them in a single hand?

@Corporis 4 жыл бұрын

There are a couple of tendons on that part of the wrist. It's likely that one of them is the Palmaris Longus and the other is a different wrist flexor tendon

@jazzadieu 4 жыл бұрын

@@Corporis ohhhh

@rishumishra2050 3 жыл бұрын

I don't have this but who knows if we are an alien hybrid.

@ivaniliev2272 4 жыл бұрын

I don't have spare parts.

@coffeech.1838 5 жыл бұрын

404 subs???? Wat happened

@Corporis 5 жыл бұрын

Pretense IsFunny I actually started making videos consistently. And people seem to like thT

@livelaughlearningdisabilit1677 4 жыл бұрын

I don’t have it now bow down to me for I am superior

@Corporis 4 жыл бұрын

we are not worthy

@prayersonfire 3 жыл бұрын

I have it :D

@ImABeez 2 жыл бұрын

I don’t have a tendon on my right arm! I guess Im rare

@saadiarai5175 3 жыл бұрын

I don't have it Respect me I'm your king 🤣🤣🤣

@bdayrainbow7 2 жыл бұрын

I dont have a palmaris longus

@pitpotdeeerste 4 жыл бұрын

Human is a description of those that go above their nature and instinct, the perception that human is synonymous with homo sapiens or humas is wrong. Looking a entomology it makes no sense. The brits thought they were the only ones having this behavior, so with the english language this became synonymous with homo sapiens as brits all thought they were human. When in relaty most ppl follow their instincts and dont present actual human behavior. human was first coined by Samuel Johnson and was derived from humankind, which means that a human strives from something bigger then them self. Most ppl today dont, they eat work and sleep, this is not the human behavior Samuel Johnson described.

@caihender Жыл бұрын

yea no i dont have it

@ecclesiastes1175 3 жыл бұрын

I don't have this in either hand. I am more evolved. :)

@erendripaeger9875 2 жыл бұрын

Same :)

@isee8936 4 жыл бұрын

A have a little

@AJ-ss7im 3 жыл бұрын

I don’t have it, see you later chimps lol

@Corporis 3 жыл бұрын

Super evolved mega brain!

@steilhander_II 2 жыл бұрын

I have it therefore I am closer to MONKE than those who don't.

@deebz2626 2 жыл бұрын

I'm evolved

@comicluigi7 3 жыл бұрын

Return tô monke

@steavendamo2251 4 жыл бұрын

You wont believe this!!! i have 3 to my rigth and 2 to my left. .do it make me more superior

@Zafrael00 3 жыл бұрын

Reject humanity become monke

@CatsInDungarees 2 жыл бұрын

I feel like it's there but people are just Hella obese

@Vaguspostedat 4 жыл бұрын

Plantaris muscle?

@Corporis 4 жыл бұрын

Great muscle. 10/10

@Vaguspostedat 4 жыл бұрын

@@Corporis q But plantaris can also be absent sometimes, it can also be used as graft

@Corporis 4 жыл бұрын

R R True

@Vaguspostedat 4 жыл бұрын

Make a video on the recent muscle ,tensor of vastus intermedius,please

@Χριζαϊων_Ζηνόβῐος 2 жыл бұрын

"Evidence that humans are still evolving" is the dumbest sentence I've heard in a long time. Do people thing evolution stops?

@pitpotdeeerste 4 жыл бұрын

the double posts are a bug, i am un able to remove any of the double posts

@pitpotdeeerste 4 жыл бұрын

the double posts are a bug, i am un able to remove any of the double posts