http://www.yogajournal.com/slideshow/yoga-anatomy-neck-safety-supported-shoulderstand/#1
Anatomy 101: Understand Neck Safety in Supported Shoulderstand
BY RAY LONG, MD |
How to prep for—and properly prop—Supported Shoulderstand, for a happy, healthy neck.
In Light on Yoga, B.K.S. Iyengar wrote that the importance of Salamba Sarvangasana (Supported Shoulderstand) cannot be over-emphasized. “Sarvangasana is the Mother of asanas,” he wrote. The pose is said to flush out the lymph nodes, help regulate blood pressure and heart rate, strengthen the diaphragm, and stretch the chest muscles. Yet despite these benefits, many practitioners steer clear of Shoulderstand.
The primary concern is that Shoulderstand puts too much pressure on the neck, or cervical spine, which can lead to injury. While there are situations in which Shoulderstand is expressly not indicated—say, if you have high blood pressure; a neck injury; glaucoma; or a cervical
spine condition, such as arthritis, rheumatoid arthritis, or degenerative disc disease—many yogis can safely find comfort and ease in this inversion, or a modified version of it.
Think about it this way: Most of us can touch our chins to our chest, as in Jalandhara Bandha (Chin Lock), without discomfort or injury. However, when you’re in this flexed-neck position and then add the weight of your entire body, the pose can become dangerous. The key to staying safe is to ensure that you place your weight on the tops
of your shoulders and the backs of your upper arms as
you stack the shoulders, hips, and legs in a vertical line.
The Anatomy of the Neck
To do this, it helps to understand the anatomy of the neck. The cervical spine is comprised of seven vertebrae
that move with each other to flex (forward, as well as side to side), extend, and rotate the neck. The uppermost cervical vertebra, C1, is called the atlas; it has the greatest mobility for flexion and extension, with about a 5o-degree range of movement between it and the skull (occiput). Add to that the range of movement of the vertebrae under C1 (C2 through C7), each of which flexes and extends about 1o degrees, and you see how the neck is actually quite mobile. While this mobility is fine when we’re sitting or standing—with only the weight of the head on the neck—imagine Shoulderstand, with all of the body’s weight resting on a neck in full flexion. You can see how that could strain the neck’s intervertebral ligaments. What’s more, a sudden slip or tumble could take the neck beyond its normal range of motion and result in injury. The trick to keeping the bulk of the weight on the shoulders (and off the cervical spine) is to have flexible, open shoulders. If the shoulder flexors and adductors are tight, you won’t be able to comfortably reach your arms behind you, which in turn will cause the spine to round, the chest to collapse, and your body weight to push into the back of your neck. To prepare for Shoulderstand, you must first open the chest and front shoulders, including the pectorals, anterior deltoids, coracobrachiales (long, slender shoulder-joint muscles), and biceps. This allows the arms to extend more fully behind you during Shoulderstand—in turn enabling your hands and elbows to become like a doorstop, bolstering the back and distributing your weight over the tops of your shoulders and the backs of your upper arms, which lightens the load on your cervical spine.
Prop Use in Supported Shoulderstand
Now a word about blankets, which many yoga teachers suggest using to safeguard the neck in Shoulderstand. In my opinion, the blanket-stacking method can actually increase pressure in the lower cervical spine, because
it focuses the flexion of the cervical spine onto the C5 and C6 vertebrae, which are at shoulder level when in Shoulderstand. If the shoulders, hips, and legs can’t stack in a vertical line, your body weight will concentrate in the neck’s intervertebral ligaments from C5 down to the first vertebrae of the thoracic spine (T1), while C4 and higher drape over the edge of the blankets in an unnatural curve. To attempt to correct this, many practitioners move their shoulders closer to the edge of the blankets. However, this increases the chance that you’ll slip off, suddenly bringing your body weight onto your fully flexed cervical spine.
The Solution
Support the shoulders without over-flexing C5 through T1. Try using two folded blankets stacked on either side of the spine (as shown above) to support the shoulders, which creates a channel for the cervical spine and maintains a natural curve in the neck. Or practice with a chair supporting your lower back and legs (as shown in the slideshow below), which reduces pressure on the cervical spine.
The growth of yoga is certainly bringing increased awareness of the potential for injury. Of course, avoiding harm is essential to the practice, yet too much worry leads to a fearful mindset—not to mention missing out on beneficial asanas. Rather than abandoning poses like Shoulderstand, explore preparatory poses like the ones that follow to make the final pose more structurally sound.
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