Muscles of the eye - extraocular muscles and movements

The muscles that move the eye within the orbit appear straightforward at first sight, but the ways in which they work together to move the eye can lead to confusion. Let's look at the anatomy!
When looking medially, the superior oblique muscle depresses the eyeball/direction of the pupil & the inferior oblique elevates the eyeball. Not what I said at the end of the video. The cranial nerves of the extraocular muscles will describe this more slowly & clearly. I hope.
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[@AkingAquila]

This video is highly underrated! I could not for the life of me understand why the Superior oblique caused depression (and the converse, why the Inferior oblique caused elevation). I had watched several videos (KenHub and AnatomyZone) and they all just stated the actions of the muscles. Dr. Webster here was the only one who took the time to explain the axes of the eye, and how the various muscles crossing those axes result in their primary and secondary eye movements. BTW the answer to my question was that the Superior oblique actually runs anterior to posterior, so when it contracts, it pulls the anterior portion of the eye downwards! Hence the depression. I'm sure I'm not the only one who had that problem haha. Dr. Webster, you've got yourself an extra subscriber! Thanks for the great, hands-on explanation!

[@olivia31192]

So so true! Thanks so much Dr Webster!

[@AliAhmed-rr6ny]

exactly what happened with me

[@cowsmoon5115]

I totally understand everything as to what you had just said there...

[@expectopeetrrronium7349]

still didnot understand why sup oblique cause depression. pls explain

[@hiefia8568]

@@expectopeetrrronium7349 muscles have an origin point and an insertion. When they contract, they move the organ they are attached to toward the direction of their origin. The superior oblique muscle moves from the back of the orbit( posteriorly) along the side( medially) until it gets to the trochlea where it switches direction from medially to laterally. From here it moves from front to back( anterior to position). The ability of the superior oblique to depress the eye occurs when the eye is moved medially. I think this eliminates the contribution of the medial to lateral angulation of the muscle. Hence your eye is stuck with only the influence of the anterior to posterior angulation. And since the muscle will pull towards the origin and since the anterior has become the "origin" in a sense, your eye will move from back to front. But remember that the eye is now adducted ( medial ) so your final eye direction will be down toward the side( ie inferomedially).

[@valentinemcdermott]

6:50-7:30 deals with the anatomy of the superior oblique and is an excellent explanation of why the SO can cause depression of the eye.

[@indianindian7757]

Tysm for this

[@jamescartwright387]

I've lived for 25 years without knowing that my eyes rotate...mind blown

[@ShreyaRajgopal]

Amazing clarity. Also, you look very much like Dr. House.

[@mcmoodoo]

Incredible clarity! Super comprehensive! 24 minutes of pure ocular value!

[@lexihernandez4191]

Ive been watching your videos for couple months now, and I just wanted to say your passion for anatomy is inspiring. Thank you, for teaching and possibly never even being able to see the fruits from which the seeds you have planted.

[@s.a5590]

I am so bored for lockdown so I here just to learn something new haha

[@andreiacastanheiradasilva8287]

While it's easy to just memorize the actions, it's hard to really understand it deeply - thank you so much for not being concise and really care to explain the logic behind it all! 👏 Your video was, amongst all the other videos I've watched and all the descriptions I've read in textbooks, what helped me most! I'm sure your channel will be accompanying me through the rest of med' school 🤗🙏

[@rohangandhi28]

You are amazing man, I mean I was struggling to understand the “complex” movements of SR, IR, and SO,IO. Thanks for explaining!!

[@ruby-pm8zw]

first of all- beautiful eyes, secondly thank you I will be spending NYE with you- so happy New year to you and to every student on this platform

[@nataliebray]

This video helped me understand the extrinsic eye muscles for my anatomy practical exam. Thank you so much!

[@Mariam_oluwaseyi_]

Finally! Whew. Your explanation is so explicit I'm so grateful

[@ruthdominguez1542]

Watching your videos helps me understand the concepts. Thank you!!!

[@user-fg7px8jp5c]

Thank you very much for this video! I had so much doubt studying the extraocular muscles movements, and was at the same time wondering why everything goes in the opposite direction in the H test! I agree with you that these take a bit studying, but it’s now much more better after your explanation. Thanks again!!

[@nsglaasakr8217]

I have been searching for a compelling explanation for the written actions of the extra ocular muscles and u r the best....ty so much

[@prithvirajbanerjee1547]

Whenever I'm stuck with some anatomical problem, I know there's one man I can look up to for solution, and that is Dr Sam Webster. You truly are a great teacher sir. Thank you very very much for posting these gems.

[@souviksikdar3180]

Tomar pod marboh

[@toniencheff4046]

Happy New Year, Sam to you and your family. I hope you all had a great Christmas. I saw the video with you getting the Christmas tree with your wife. I am very grateful for your excellent videos. Thank you from the bottom of my heart.

[@irenacastle5482]

Best explanation I have found. Not even expensive anatomy books touch on this.

[@juliethomas8401]

Beautifully explained !!

[@kathmandunepal9547]

OH MY GOD! Its been 5 YEARS!! Since 5 years i was soooo confused about how superior oblique could cause the eye to look down when it lies upward! I checked for videos back in 2014, didn't find any! Finally you've made that point super clear!

[@gopalreddy7582]

I still didn’t get it can u explain me pls

[@user-zu8lq8qe2y]

You've made this so interesting. Thank you!

[@palashbinayake6904]

Thank you sir, this video made it easy to visualise and imagine how those muscles work , excellent job.

[@danielpa8644]

Excellent lecture, especially the part where the bony cavity AP axis that holds the eyeball and muscles is actually laterally deviated. So when pupils appear to be in the center of the eyeball the pupils are actually medial to the bony AP axis. This is why the eye muscles cannot work in isolation. Because the muscles are attached past the vertical and horizontal equators the eyeball, contractions of the eye muscle cause the eyeball to move along multiple planes. This is why the inferior oblique muscle pulls the eyeball up and out. The name of the muscle is just its location not its function. How this was engineered is incredible.

[@sriparnaacharya2696]

This is the best video on movements of eye ball.. Thank you so much sir...

[@amanagarwal2746]

Superbbb... Sir And the thing you said at the end was just amazing

[@rbg7408]

When fun and wisdom goes together... thank you sir!

[@qudsiashakeel7920]

THIS WAS AWESOMEEEE!! thank you Dr.Webster

[@pc_opinions]

An excellent video on eye movements. Great job!

[@yixuan_yx]

Great explanation. Thank you so much!

[@gavinpersaud4243]

excellent video and good commentary. Thanks mate

[@puneetkantiwal8097]

Awesome video man! U cleared all my doubt, great job! Thanks a lot

[@muskangaba4341]

Thank you for giving everyone an access to quality medical education ❤️

[@IldaBegic-wz8oe]

Thank you so much! I`ve been looking for this kind of explanation forever. You saved me 🥰

[@hebaelnabawy8871]

I have watched several videos and didn't want to watch this since it's longer but seriously this is the best and I've wasted more time by watching the other videos wish I've watched this earlier. Thank you wish you all the best doctor :D

[@szehonyu7325]

That's so useful! Thanks man!

[@kalpanayadav2836]

Thank you for making it easier to understand 😊

[@zeelpatel8049]

Very well explained.Thanks.

[@user-ke9jl9uy1q]

Excellent explanation, Dr.! I've become your humble subscriber😊 Thank you!!!

[@mlemay2486]

Other than the excellent explanations.. you make me laugh! I love your humour :)

[@PatDotto]

Amazing explanation!! Tks ❤️

[@gaynorankamah7381]

Great video, thank you.

[@kikibear12146]

Well done video!!!

[@debarghapati8917]

I have no words to thank you.

[@shavisingh6393]

Thank u soo much sir for interesting demo nd stressing ur eye . Great work

[@user-mr7or4yj1i]

Amazing tutorial

[@clarisalolita4783]

Thank youuu for the great explanation

[@elchin571]

thank You for great explanation!

[@MustafaAli-ug3qw]

Brilliant, thank you so much.

[@omarisam3650]

excellent video!! thank you

[@h0m0.sapien]

Simply amazing!!

[@mariashieladolosa8239]

I need to watch this video. Thanks to you Sir. I like your accent, it's very nice to hear.

[@amulcool7229]

Thank u so much sir❤️❤️❤️.... Literally searched every other video but never understood the secondary and tertiary actions of oblique muscle...

[@DrCarlosAndresGarcia]

This is the best video i’ve seen of the movements of the eye🎯. I’ll upload mine version in spanish this weekend!

[@lyndawson7567]

good stuff

[@hilal5159]

omg what a perfect teacher, cause of the pandemy I'cant go to university and can't do our lab lessons conclusion of it I can't picture these anatomic structure in my head but this video helps so much. thanks a lot

[@watermelonsugar_1535]

Thankyou so much, my confusion about intorsion and extorsion is resolved. 😊

[@mzml4696]

Even a non anatomist like me can make sense out of it. Nice and interesting Sam . :)

[@tommybryant4985]

Wonderfully informative 🫶

[@anandvarunachari5938]

He is amazing ❤❤

[@countto5591]

Very helpfull...man..really thank you

[@albaqary91]

great effort , thanks

[@VMGChannel]

Really helpful. Thanks

[@kishorekumarbangi512]

Nice job.

[@clearwavepro100]

Wonderful thank you!

[@YH-nr7my]

thank you so much! it was the most helpful video :)

[@ramahmardini222]

the best anatomist evvver

[@priyankarane6554]

Just love you for this one 😊🤗 I like that color of your eyes.. Seriously 😍😘

[@rajatsingh24k]

The insertion points and the fact that the axis of the eyeball in the normal physiological setting (baseline) is different from the axis of the orbit are key. Watched 4 other videos before this one and they were all sh**. This video is the only one so far that made this concept clear. What an amazing teacher. Med schools should just show Dr. Webster's videos for anatomy and save everyone a ton of time!

[@libertymedianews]

Informative 👊

[@fatimakhalid1991]

Amazing!

[@rezarezanaghibi]

Wow terribly informative 😮

[@Knucklesdeadlypunch]

Thank you so much Dr. For sharing your knowledge now I have a better understanding of eye movement and I can finally help my anxiety bc I have a better understanding. Again thank you. Be blessed 🙏🏾🙏🏾

[@rafiatajani1712]

How would it cure your anxiety tho

[@Jomanaagh]

you are amazing , thank you very much .

[@Soaresbrook]

Excellent video, man. i could be sure i've got trochlear palsy after your explanation of eye rotation, It keeps the horizon in the healthy eye, but it doesn't in affected eye.

[@user-dz8ky8cl8k]

U are really amazing!

[@lenaatyat5186]

You’re the best ❤❤❤

[@medicine4094]

i really ask god to bless u every day

[@aydaradfar9676]

Thank You !!!

[@ngocminh8068]

Thank you again

[@missunknownps3]

Superior oblique causes intorsion Inferior oblique causes extorsion When they work together they cause Abduction Superior oblique pulls eye down Inferior oblique pulls eye up THANK YOU FOR EXPLAINING THIS IVE BEEN LOOKING FOR A GOOD EXPLANATION!

[@igorlimamaldonado725]

Excellent.

[@saddikhaddad1586]

Thank you Sir!

[@duocphamtruongtho4462]

Thanks very much!

[@rahavpokhrel8748]

Awesome!

[@Chrysolite-kn3mz]

Thank you so much Dr Webster; you explained all so well, especially the reasons behind the actions of each muscle, which all kind of depend upon the axis they lie upon.. as I was watching your video, I came to a realization how unique and amazing God's creation are.. thank you.

[@gladysmartinez238]

Thank you!!!

[@kareenabudhrani9261]

This is sooooo gud ... SO was irritating me and I got it now.

[@shorouksalem5371]

More than wonderful

[@keertidpai7939]

Thank you sooooooooooooooooooo much

[@jibansharma4227]

It was damn impressive. made it so easier to understand. big thanks Sam. Best in the internet for extraocular muscles.

[@jenniferzhou4264]

very usefully thank you

[@sumitkumarsah5161]

🔥🔥 Love from Nepal

[@stevensouter6169]

Hi Sam. Great Video: Question: Is it more straining to look up or look down? Why is this the case?

[@rafal3941]

Thank youuuu really I mean it you’re pretty good ❤ الله يوفقك

[@dr.zaynab4450]

Ilove u llove lesson to your lecture ..really thanx to you ♥

[@shwanmussa674]

Dr. zaynab Hello Miss Zaynab from where you are ?

You are great.

[@anfaljaryan4268]

you are amazing

[@sibunal7410]

Why so good 😭

[@jamesdaley1852]

good stuff

[@grrahrawr5688]

Cool video :)

[@muhamedfaour4629]

Thank you, love your lectures.