“. . . according to the Yoga Sutra (3.1), the term [Bandha] refers to the ‘binding’ of consciousness to a particular object or locus (desha), which is the very essence of concentration.”
Georg Feuerstein



Saturday, March 19, 2016

Shoulder Biomechanics, Part III: The Supraspinatus Muscle


Hello Friends,

Let’s cap off the muscles of your rotator cuff with the supraspinatus. This muscle originates in a trough-like area above the scapular spine, hence its name supra, which means “above”. The supraspinatus then inserts onto the greater tuberosity just behind where the long head of the biceps enters the shoulder (figure 1).

(We’ve covered the subscapularis, infraspinatus and teres minor muscles along with some key biomechanical points about each muscle—click to review.)




Figure 1: The supraspinatus muscle of the rotator cuff (with the infraspinatus and teres minor faded).


Contracting the supraspinatus abducts the humerus at the glenoid socket (takes the arm out to the side) for the first 15 degrees. After that, it becomes a synergist of the deltoid for abduction. As with the other muscles of the cuff, the supraspinatus also stabilizes the humeral head in the socket. Figure 2 illustrates this in Warrior II. 


Figure 2: The supraspinatus contracting to synergize the deltoid in abducting the shoulders in Warrior II.


The supraspinatus is the rotator cuff muscle that is most frequently torn. Tears start to become common beyond the age of forty, with an increased incidence in each decade of life. Figure 3 illustrates a supraspinatus rotator cuff tear.



Figure 3: Full thickness tear of the supraspinatus muscle (with the long head of the biceps shown in front of the supraspinatus).


Drawing your arm across the chest (adducting it) stretches the supraspinatus, as well as the capsule of the shoulder and the deltoid muscle. Figure 4 illustrates this action in Garudasana. Note the muscles (colored blue) that contract to stretch the supraspinatus and the muscles that also stretch in this pose (colored red). 


Figure 4: The supraspinatus muscle stretching in Garudasana. The muscles in red are stretching and those in blue are contracting.


Click here to take the rotator cuff quiz to test your knowledge!

Thanks for stopping by. Stay tuned for the next post when I'll go over the interaction between the deltoid muscle and the rotator cuff. By the end of this four-post series, you'll have a good understanding of the functional anatomy and biomechanics of the shoulder joint as applied to yoga. Click here to browse through the Bandha Yoga book series on anatomy, biomechanics and physiology for yoga.


All the Best,


Ray Long, MD

16 comments:

  1. a fabulous article, thank you. I'm also loving your key muscles/poses books which I refer to a lot.

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    1. Thanks for your comment, Julie. Glad to hear you enjoy the work! Ray

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  2. Thank you.. Looking forward to more educational shares.. Namaste..

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    1. thanks for stopping by, Anil. More key biomechanics coming this week. Best~Ray

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  3. Not only do you explain yoga anatomy well, you make it interesting too. Your blog and books help me in a very challenging area.
    Thanks for all you do.

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    1. You're welcome, Linda. I'm delighted that you enjoy my work. All the Best~Ray

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  4. Working through pt for slap tear, 3/4. Your article is very helpful!

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    1. Good luck Steve--glad to hear the article helps. Ray

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  5. Thank you for the explanation and the beautiful pictures ! Quick question: could a tear shown like in fig. 3 heal without surgery ?

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    1. You're welcome, Natacha. I'm delighted you enjoy this. In answer to your question about whether a full thickness cuff tear could heal without surgery: no, cuff tears do not heal without being re-attached surgically. That said, many people live with cuff tears and do not have symptoms (or surgery), especially in the older population. Part of this is because other parts of the cuff compensate. The decision to surgically repair the cuff is based on the clinical picture of the individual. This includes age, symptoms, size of the tear, state of the torn cuff (atrophy), reparability etc. It's a very big subject. Hope this helps--Ray Long, MD

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  6. Thanks guys!! Always appreciated. :)

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  7. I've enjoyed and referenced your blog posts and other online content for several years and I finally went ahead and purchased almost all your books. (I still need the inversions one.) I wanted to let you know that the quality of content you share online was my biggest motivator in finally spending the money to purchase them. Thanks.

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  8. Thank you,my english is not very good but I unferstand. I really ejoyed your articles and your books. I refer to a lot.

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  9. Hi Ray,
    Your post is very important and very informative. Its very helpful for every one. hope you publish your next article soon.

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  10. Great information from an anatomical aspects on Yoga on your website.

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