Infraspinatus: Learn Your Muscles

The infraspinatus is one of those enigmatic rotator cuff muscles. The rotator cuff can be the root of all evil for some people, so this month is dedicated to learning about this troublesome structure and how to keep it healthy.

There are four muscles in the rotator cuff. They are the supraspinatus, infraspinatus, teres minor, and subscapularis. The infraspinatus, which we will focus on today, helps rotate the head of your humerus outward, away from the midline of your body. This is essential for good posture.

Location

infraspinatus

Thanks to Yoganatomy for the image.

The origin of the infraspinatus is on a landmark called the infraspinatus fossa. This is the ridge on the scapula just below its spine. The exact origin is on the medial two-thirds of the scapula’s dorsal surface just below the scapular spine.

Infraspinatus inserts on the posterior aspect (the back) of the greater tubercle of the humerus. The greater tubercle of the humerus is the bony nodule that is further from the midline of your body.

So, this muscle runs below the scapular spine, from the edge of your scapula closer to the midline of your body to the back of the larger notch on your humerus. It fills in the rest of the back surface of your triangle-shaped scapula with the supraspinatus.

Function

The main purpose of the infraspinatus is to laterally rotate the humerus at the shoulder. Lateral rotation, in this case, is when the head of the humerus turns outward, away from the midline of the body. This movement is essential for good posture, but be careful not to overdo it. A little bit of lateral rotation goes a long way, and too much will cause an injury.

Another duty of the infraspinatus is to stabilize the glenohumeral joint. The glenohumeral joint is a fancy name for your shoulder joint, and all rotator cuff muscles contribute to the balance of this joint.

Common Dysfunction

Anyone who has ever torn a rotator cuff muscle will tell you that there are a number of ways to injure these muscles. According to Yoganatomy.com, the infraspinatus is the second most commonly torn rotator cuff muscle. Baseball pitchers also commonly tear this muscle, and you can also injure your infraspinatus if you dislocate your shoulder.

Restoring or Maintaining Health

If you believe that you have injured or torn your infraspinatus, contact your doctor. Your doctor can order the appropriate imaging, therapy, and medicine necessary for your recovery.

However, if you feel like you have a muscle tightness or weakness and are wanting to improve the functionality of this muscle, I have some suggestions.

To strengthen the infraspinatus, practice Side plank. This is both a Pilates exercise and yoga pose. However, only yoga offers really great options for stretching this muscle. Any time you bring your arms behind your back (like for binds or reverse namaste), you’ll find a stretch for the infraspinatus. You also get a stretch in your lower arm during Gomukhasana.

More Information

I consulted The Concise Book of Muscles by Chris Jarmey. Recently, the book was revised and is in its third edition. I love this book as a quick go-to guide for easy to understand anatomy.

For those who are more interested in technical terminology and smaller muscles, I recommend Flash Anatomy Muscles Flash Cards. Any time a client comes to me with pain, I use these flash cards.

Also, I consulted David Keil’s article on the infraspinatus and teres minor at Yoganatomy.com.

What’s your favorite rotator cuff exercise? Let us know in the comments below.

Thank you for reading this article. If you enjoy the information supplied, please consider supporting this website!

Sign up for our newsletter to get more tips for health and happiness! Also, you can find us on FacebookYouTube and Pinterest as Custom Pilates and Yoga.

Sharing is caring!

About Sarah Stockett

Hi! I'm Sarah, and I'm a certified Pilates and yoga instructor with a passion for pain relief. When I'm not working with clients, I'm researching the best ways to get rid of pain. Do you want to learn how to practice yoga and Pilates safely in your own home? Or, do you want to know all my tips and tricks for pain relief? Join my mailing list and receive free goodies to help you.

2 Comments

  1. Brenda García Lopez on July 1, 2018 at 3:32 pm

    What exercises to strengthen the supraspinatus?



    • Sarah Stockett on July 1, 2018 at 9:44 pm

      Hi, Brenda! Thank you for asking. If you’re wanting to strengthen your supraspinatus, you’ll want to practice any exercises where your straight arm lifts out to the side. This is the sort of arm movement that you’ll find in the yoga poses Warrior 2 and Triangle pose. You’ll also find this in the Pilates exercises Saw and Spine twist. Another good option is to practice Side plank. With all of these exercises, you have to be absolutely certain that your shoulder is in a neutral position. Working your muscles to the point that you lose your form is never a good idea.



shares