Years ago, I was teaching a workshop for yoga teachers focused on the anatomy of the shoulder joint. One of my students mentioned that she was suffering from chronic shoulder pain in Adho Mukha Svanasana (Downward-Facing Dog Pose). As she demonstrated the pose, I saw that she was dropping her shoulder blades down her back (as commonly instructed in many poses). I suggested she internally rotate her upper arms to release and rotate the scapulas (shoulder blades) and move them toward her hands. Her pain disappeared—and she later told me it never returned.
Many yoga teachers and students hold a fundamentally flawed understanding of how the shoulder joint moves. For example, externally rotating your upper arms in Down Dog while holding your scapulas down can, and regularly does, impinge the supraspinatus tendon (part of the rotator cuff) between the scapula and the head of the humerus (upper arm bone). This can contribute to pain, tendinitis, and tears in the tendon.
Sometimes we need our shoulders to move freely in asana practice, like in Urdhva Hastasana (Upward Salute), to work on reaching up and elongating the torso. Other times, we need them to hold still to create stability, such as in Plank Pose, Setu Bandha Sarvangasana (Bridge Pose), or Down Dog. Honoring your body’s natural structure and allowing the healthy biomechanics of shoulder movement to occur can make your practice safer and more satisfying at the same time.
Understanding the structure of your shoulder
The scapula influences movement in the entire arm. The muscles and tendons that attach to it help move the humerus, the clavicle (collarbone), the sternum, the radius and ulna (forearm bones), the carpals (wrist bones), the metacarpals (hand bones), and the phalanges (finger bones).
Scapulas are shaped like upside-down pyramids, and they are curved to fit snugly over the back of the ribs. The junction of the scapula and the humerus forms the true, ball-and-socket shoulder joint. In the front of the body, the scapulas connect to the clavicle; the front of the clavicle connects to the sternum. This group of joints must work together in harmony to allow for unrestricted, pain-free movement in the upper body.
Practice In Action: Build a better downward-facing dog
Shoulder pain is common in Downward-Facing Dog Pose. Try these tips to alleviate or prevent it: Find the pose, and inhale. On an exhalation, rotate your arms internally. Externally rotating your upper arms can entrap the supraspinatus tendon of the rotator cuff, causing pain. Push into your hands, keeping all fingers on the ground. Maintain length in the vertebral column to prevent excess weight in your shoulders.
Now, let your outer shoulder blades move down toward your neck and out toward your little fingers, which allows your scapulas to rotate naturally. Create a little muscular action between your shoulder blades by bringing their bottom tips slightly toward each other. Remember to breathe as you push against the floor, adjusting weight into your fingertips to take pressure off of your wrists.
In this pose, both your upper and lower arms should internally rotate to seat the head of the humerus in the deepest aspect of the glenoid fossa (the concave space where the humerus connects to the shoulder blade). It might help to turn your fingertips inward a little to make this happen. Let your head hang down, and hold the pose for several breaths.
What healthy shoulder movement feels like
If your shoulders are injury- and pain-free, try this: Stand up and move one arm out to the side about a foot, at approximately a 45-degree angle. Notice that the scapula doesn’t move much. Then, continue moving your arm above your head. You will immediately feel the scapula start rotating and elevating (as long as you don’t interfere with it by dropping your shoulder down your back).
This scapular rotation and elevation happens naturally as you move your arms overhead in abduction and flexion (moving your arms to the front of your body) and helps prevent injury to the shoulder joint. If you try abducting your arms over your head without moving your scapula, you‘ll likely feel stuck about halfway up. Here‘s another way to feel normal scapular movement: Imagine that you are reaching up for something on a high shelf. Stretch without thinking about the movement. Allow the outside of your scapula to rise. Feel how much freedom you have to move in your shoulder joint.
Adapted from Yoga Myths: What You Need to Learn and Unlearn for a Safe and Healthy Yoga Practice by Judith Hanson Lasater.
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