with contributions by Keith Wittenstein. Special thanks to Sarah Court, Dinneen Viggiano and Trina Altman for editing and feedback

This article is Part 2 in a series on shoulder biomechanics.

shoulder bonesIn the first part of this article, we discussed cues and teachings that are passed down via teachers and the potential problem that can create with cueing – specifically, the cue “move your shoulder blades away from your ears”. Let’s begin with one of the most important things to know about the shoulder joint complex. It’s not just one joint. It’s four. When you peel back the skin that curtains the shoulder stage, all four of these joints need to work together to allow for the arm’s broad range of 180 degrees of flexion when the arms are alongside the ears. What happens “on stage” appears exclusively like movement of one bone, the arm bone. Meanwhile, what’s happening backstage is a coordinated co-movement of several bones at several joints. Three bones fit together to make up these four joints. They are the arm bone (humerus), the shoulder blade (scapula), and the lesser known and frequently forgotten about collarbone (clavicle). We will refer to these bones by both their Latin and English names throughout the rest of this blog.

Let’s learn how these bones articulate at these joints.

The first and most famous joint we’ll talk about is the glenohumeral joint. This is where the head of the humerus and the scapula (via it’s articulation with the glenoid fossa, or the shoulder socket) move relative to one another. In layman’s terms: the shoulder joint is where the arm bone attaches to the shoulder socket which is located on the shoulder blade! This joint tends to command most of our attention since it allows for movement that is very accessible to us perceptively. When we look at ourselves in the mirror, the humerus appears to hang right off the side of our trunk and when we go to lift it up overhead, its movement is very noticeable and seems to take place separately from the torso.

However all 3 bones – the humerus, the scapula and the clavicle – participate in positioning the humerus overhead. The perceptual difference being, the humerus is on stage (a comedic actor, perhaps), while the other two work backstage behind a curtain of upper torso tissues that mask their cooperation. Just as when an actor performs on stage, we do not see her lighting and costume designer at work, but rather the evidence of their work in her appearance, so too, the movement of the humerus is the result of a coordinated effort whose support crew goes unseen. Past the first 30 degrees of the humerus’ upward movement from the trunk, the scapula and clavicle move too. Their co-movement facilitates continued upward movement of the humerus. Simply put, without this backstage support, the humerus show would not go on.

Another of these crucial, behind the scenes shoulder joint players is the acromioclavicular joint, or the AC joint for short. This is where the acromion process of the scapula articulates with the lateral end of the clavicle. The acromion process is a witchy-like finger projecting out of the scapula and pointing from the back of the shoulder to the front. It is the highest point of the shoulder. Acromion comes from the Greek roots akros, “highest” and omos,” shoulders.” This joint does not allow for a great deal of movement between the scapula and the clavicle. In fact, it is most often injured when forced to allow for movement that it isn’t structurally designed to permit. Therefore, due to its limited mobility as a joint, when the clavicle moves, for the most part, we are best to let the scapula move with it. This is a key point that will come up often in our discussion of a more skillful approach to positioning the scapulae when the humeri are overhead.

Another of these crucial, behind the scenes shoulder joint players, is the sternoclavicular joint, or the SC joint. This is where the top of the breastbone (manubrium), provides a fulcrum point for the clavicle to rise when the arms reach overhead. This movement of the clavicle is called elevation. We will explain why later in this blog post, but for now, know that when the arms are overhead, the clavicle must elevate a full 30 degrees. Remember that the clavicle attaches to the scapula at the AC joint – that relatively immobile joint that we said we’d be mentioning a lot. This means that when the clavicle elevates, the acromion process part of the scapula must move upwards (toward the head) along with it.

Upward rotation of the scapula.

Upward rotation of the scapula.

In the image to the left, the scapula has spun a few degrees, like a turntable, to allow the acromion process (the witchy finger projection on the scapula that forms the AC joint with the clavicle) to move upward. This movement of the scapula is called upward rotation. During upward rotation, the bottom angle (inferior angle) of the scapula rotates upward. Remember that the AC joint does not structurally allow for one of its bones (the clavicle) to move up while the other (the scapula, specifically the acromion process of the scapula) moves down.

Unfortunately, this is what you ask those two bones to do when you work scapular depression (pull your shoulder blades down) while the clavicle elevates to assist in taking the arms overhead. Doing this creates a stressful dissonance in the soft tissues surrounding the AC joint. These tissues find themselves caught in the middle of two biomechanically conflicting goals: the upward effort of the end of the clavicle and the downward effort the practitioner makes on the scapula.

Keep tuning in this month for the rest of this series, Uplifting News for Depressed Shoulders!

 

 Enjoyed this article? Read Building Balanced Shoulders.

Laurel Beversdorf

Laurel Beversdorf is an international yoga and interdisciplinary movement educator specializing in anatomy, biomechanics and yoga teaching pedagogy. She is an integrated Yoga Tune Up® teacher and trainer, the creator of Body of Knowledge™ Anatomy and Biomechanics workshop series, Yoga with Resistance Bands classes, and a senior teacher and trainer at YogaWorks in New York City. Laurel is committed to raising the bar on the content and quality of yoga education. She teaches in order to help her students reclaim and strengthen a sense of power and belonging in their bodies, the bodies through which they share their gifts and transform the world. http://www.laurelbeversdorf.com

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Jennifer

I placed my hand on my clavicle as I flexed my shoulder – in amazement of the rotational and upward movement that takes place that seems to be what you are referring to when you write about elevated shoulders. When I depress my shoulder while keeping arm overhead – it feels like it becomes a different movement and that it provides me less strength if I lower my shoulders too much. Will continue to explore this.

Siewli

Hi Laurel, I’m so enjoying your writing! For most yoga teachers, anatomy is scary and dry, but you’ve managed to make it so engaging and interesting! Please write more! You’re not just gifted as a teacher, teacher trainer, but also a writer!

Tanya

Great descriptions, especially love the imagery in the second to last paragraph.

Danielle Lee

Laurel, Thank you for taking us ‘behind the scenes’ for a more nuanced understanding of the shoulder girdle in the overhead arm position. It reminds me of the iceberg analogy – how its very tip is visible and understandable at the level of the appearance, but there is a whole mechanism of activities that are invisible. True of Yoga, and true of movements of the body.

Desiree N

Laurel, I love your analogies. You have a really amazing way of explaining what is happening anatomically in our bodies and making it understandable. It seems silly to try and pull our clavicles down while our arms are in flexion knowing that the clavicle HAS to physically move up to make this action possible yet that is what we have been TOLD to do for so many years! Again, because not enough people were asking “why are we doing this?” I’m so glad I have you to explain this to me!

Riannon

I love how you covey your brilliance through analogies that make it so easy to understand. Thank you for demystifying the complexities of the shoulder complex. Looking forward to reading more!

Lita

This is such a wonderful, detailed and engaging description and argument for not using the “draw the shoulders away from the ears” cue in the case of shoulder flexion. I had learned this in Sarah Court’s Shoulder Immersion earlier this year, but I am so thankful to have a detailed, written description. Thank you. can’t wait to read more int he series!

Rick Widdifield

I’m thinking we are going to need anti-depressants for the shoulders. The behind the scenes story of how the shoulders actually achieve their amazing range of motion is very interesting and complex, with multiple players and moving parts. I’m thinking that we are also going to need some rhythm to orchestrate this complex coordination. Very creative use of the stage metaphor with main characters and supporting actors and behind the scene crew…the stage manager must keep things running smoothly. Hopefully giving the right cues at the right time. Is that where we are going? I know, I must read on.

Heidi Schaul-Yoder

Love the image of the humorus being the “comedic actor” while the clavicle and scapula are the tech crew working behind the scenes! I have a much better understanding of the issues involved in cueing shoulder depression while the shoulders are in flexion–thank you!

Eva Hamilton

Thank you for this clean & clear summary of the multiple joints which compose the shoulder.

Jill Dunkley

Okay, I’m hooked. Looking forward to Part 3 now!

Tracey Arnold

Thanks for explaining the mechanics of shoulder flexion.

Sharon

A beautiful continuation of the previous post. I love the analogy of the the players at work “behind the scenes” of the show you are watching, I think this is a helpful way to introduce this concept to students. I have completely altered my cueing of the shoulders since participating in Jason Ray Brown’s ASFYT. I still get a bit caught up on this though – How come we are aiming to allow for natural Scapulohumeral rhythm but denying similar rhythms at other body parts such as when we spend so much time dissociating the thigh and pelvis?

Alexandra Duncan

Thank you for this very informative artilce of such an important area of our body. Many of us have such little understanding about what goes on in our shoulders and just tend to oversimplify. I, too have been cueing the depression of the shoulder blades and am now happy that I can pass on some new information to my students and explore new shoulder movements on the mat.

Monica

Extremely informative! The way you describe everything so clearly makes it easy to understand. When you understand what’s going on ‘behind the scenes’ its easy to understand why asking someone to lower their shoulder blades works against the body’s biomechanics. Thank you and I’m reading the next one in the series.

Keri

This series has been eye-opening for me, and I’m only on the second part! I was surprised to learn that this cue is not good for an overhead position, I just naturally assumed that my shoulders should be down for everything. Of course that is I why I am studying with YTU, to get rid of my previous assumptions and replace them with knowledge. In that vein, I would like to tie two comments together and hopefully understand even more. I first noticed Kimberly commented about switching up her practice to include external rotation, then I read Claire’s comment about… Read more »

Shannon Algeo

This is super interesting information that I’ve never had explained to me in this way. What I understand from reading this article is that we there is flexion in the shoulder (aka we raise our humerus bone over head), the clavicle raises up to 30 degrees. The scapula elevates and wings out slightly. The acromioclavicular join also elevates. When we work to depress the scapulae from here, we are putting incongruent pressure on the soft tissue surrounding the AC joint. Wow. Thank you Laurel. This is definitely going to impact my teaching and give a better context in which to… Read more »

Kayleigh

Learning this material last year in the shoulder immersion really changed the way I look at shoulders, especially the cues we give when shoulders are in flexion. I’ve been told SO many times to bring my shoulders down, and I think I’ve overly depressed my scapula to the point that I haven’t allowed natural scapular movement in poses and in day to day life.

Chelsea Vickers

This is getting more and more interesting as I go. Excited to read the next post in the series!

Manju Goradia

Good explanation of how the upward rotation of scapula is productive and how depressing the scapula is counter productive for raising the arm overhead.

adi

I appreciate the info & hard work, but I think this is way to technical, long, boring etc….you get the idea….I think it would help more people if it would be more simply explained

Laurel Beversdorf

Kimberly Greeff, yes! External rotation of the arms while the arms are in flexion = a SUPER important direction of movement while the arms are overhead. It’s one that I did not dive deeply into in this post – stay tuned for a future post! The shoulder girdle complex is quite complex, isn’t it? As the arms go overhead, the shoulder blades glide laterally and anteriorly in protraction (a coupled action of external rotation of the arms as they move overhead). This happens along a more horizontal trajectory. In addition, they spin, like a turn table in upward rotation. Their… Read more »

Marin

This post does an excellent job of providing a logical, fact-based explanation for why our shoulder blades move up along with our arms and why it’s so hard (and sometimes painful!) to try to keep them down. I’ve injured my shoulders several times in yoga classes and have resorted to using cactus arms or goal-post arms in poses like Warrior I, Chair, and High Lunge. I look a little goofy, but my shoulders don’t hurt!

Emma McAtasney

I’m guilty of cueing pulling the shoulder blades down when lifting the arms overhead. But no more! Thank you for writing this series on Shoulder Biomechanics. Just what I feel I need at this time. My shoulders are definitely huge blind spots for me in my body.

sarah soggs

Great topic! The shoulders are so much more then the humorous and what everyone looks at as the shoulder disregarding the scapula- and clavicle- all floating and begging for stability!!! Well illustrated connections!

Leslie

The shoulder is not one joint, it is four!
(is the scapula articulating with the ribs considered a joint?)
This is good stuff, and you are doling the informatation out in such tasty tid bits!
You are a compelling writer, Laurel.
Looking forward to revelations in the next installment!

Claire

Hi,
it’s very interesting to see that pushing the shoulders down is not a good thing to do when lifting the arms. However, I think that what we’re really meaning with that is replace the scapula in the back, rather than having them hunched up on top of the trunk. . If the shoulders are rolled forward the lifted arms will do damage to the soft tissues. The scapula must slide up the back, rather than rocking over the shoulders. I think this is really the point of “shoulders away from your ears” at the beginning of warrior positions for example.

Renee

Excellent explanation of the coordination of the multiple shoulder joints. I experience a lot of impingement with shoulder flexion, and now I have a better understanding of why. As I’m a huge inversion junkie with former rotator cuff tear and surgery, learning how to better align my shoulders and prevent pain and further injury is so key!

Judith

I’ve always cued yoga practitioners to lower their shoulders away from the ears – this information is very valuable to help guide to a healthier place – thank you.

Lynn

Yes, I can feel that pinch! Embody the body

Sarah

Wooohweee, you just blew my mind with this. I always cue shoulders down in Warrior I. I only address the muscles not the bones/joints. The light bulb just went on. I am going to have to go play with the bones to figure out the correct cue!!!

Sara

Thank you for this articulation of how the joints of the shoulder move. I am starting to put together the actions of the shoulders and the muscles and bones. This article is a nice foundation piece for my growing understanding.

Kimberlee Ott

Great article!! love the reference to front/backstage!! I learned about not cuing to pull the shoulders down from over doing it and injuring my shoulders. Its a really bad overused cue.

Ben Pace

Awesome very great descriptions. I will be paying much more attention to my ac joint.

Debra Forselius

I am at a teacher training level 1 and I found this as a great reminder of the 4 joints of the shoulder and 180 degree Rom. Wow I wish in hinesiigt that i read this first before I did my homework. Thank you for the 4 joints and 3 bones.

Michelle Corbeil

I also loved the analogy about actor and behind the scenes players. This common cue to bring shoulder blades away from the ears as with most miscues is an oversimplication to get majority of class to relax but has indeed brought with it different issues. Thank you for breaking down actual movements at joint for better understanding.

DEBBIE SMITH

Laurel thank you for posting this informative article ,I also was never comfortable using” depress your shoulders” instruction All bodies are different and instructions are interpreted differently the human body can never be a one size fits all.

Julia Lamm

Laurel thank you for taking time to explain “shoulder blades down” movement. It is one of the most used instructions in yoga classes. Now I can visualize various structures of the shoulder making it happen. It will help see a certain pattern in the student’s body. I loved your “stage” analogy. Very creative.

Claire

The shoulders, what a LA highway system, this will be a very helpful article to help clients understand that there is so much more to it.

Miriam Rigney

Laurel, this series of posts is great to clarify the actions and cueing instructions for shoulder joints movement. The points are clearly outlined and I totally agree with the one about cueing ‘shoulder blades down’ whilst flexing the shoulders. Looking forward to the third post!

Kimberly Greeff

I too really enjoyed the visual of actor/crew analogy. I have a deeper understanding of what was causing much confusion before. Thank you for breaking this down so clearly and I can’t wait to read the next portion! While I don’t experiance discomfort in softening my shoulders away from my ears I’ve stopped lifting my arms up from flexion and have begaun with external rotation > abductioin > flexion – now I’ll have to marinate on how this effects the whole stage during this “performance”!

Debra Forselius

I found this very informative, for all the movements that are involved just to have movement in the whole shoulder, what bones are in old ed in the movement for example of elevation and depression. Thanks Debra

Aracelly Latino-Feliz

The breakdown of the all of the joints involved in flexion of the shoulders helps paint a great picture of what is going on with just one movement. Multiple components to consider. One is particular is the subclavius to allow for the extra 30 degrees of upward rotation, essential for full flexion. A tight subclavius can alter forward flexion. Just one of the many things that can be off. Looking forward to reading more.

Karen

Thanks for outlining the complexities of this highly mobile and structurally complex joint structure. You not only clearly outline each of the actors involved but you also provide clarity on when each of them plays their part and which one takes the lead during the movement. I particularly like the highlighting of the dissonance in the tissues we may create by asking for two opposing movements with one cue. I look forward to the remainder of your series!

Alys

Great information to” set the stage” for more dialog on the motion or lack of motion in particular joints of the shoulder and the injuries that are apt to result from loading the tissues incorrectly.

Thu Maraia

Great article, this is an eye opener, great for my husband to read, since he is desk bound and shoulders are always, up by his ears, typing away at his lap top. This will help him to be mindful on how his schoulders , clavicle are not depressed when his hands are on the coputer key board.

Meredith Hutter Chamorro

Illuminating article. I must admit that I am guilty of cueing students to move their shoulders away from their ears. Your explanation about the stress on the soft tissues when the clavicle elevates and the scapula moves downward will have me reevaluating my cues!

Angi bloom

I look forward to learning more about the shoulders as I have limited mobility in them and find many simple postures really challenging. I injured myself while trying to depress my shoulder blades with a suitcase on each arms and realized that straining through depression was not the way to move and release the tension I was feeling.

Linda

Your explanation of the complexity of the shoulder joints is enlightening and makes clear why the common cue of depressing the shoulder blades is problematic in some poses, such as when the shoulders are in flexion. Thanks for the valuable information!

Molly

I loved your actor/crew analogy and I can’t wait to read the rest of this series – I have a feeling it’s going to completely change the way I treat my shoulders in my practice. I’ve always struggled with the common “depress your shoulders” instruction in poses where my arms are fully flexed, and now I understand why!