Twist the spine, not the SI joint

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Seated spinal twists can be a perfect ending to a yoga practice. After warming up the body, gently twisting can feel invigorating to the muscles of the spine.  Fresh blood penetrates the muscles that were taut during the twist and the compressive effect of a twist may help to nourish the discs.   In order to realize the benefits, you want to twist enough so that your whole spine rotates, not just the head, neck, and shoulders, but not so much that you strain the joints in your back and pelvis.

Finding that just right twist requires a little forethought. Seated twists, where our sit bones are weighted on the floor, are a little risky in terms of injury.  It is easy when you are in the moment to reach your arm behind you and go for it (a bind) without noticing what is happening in the pelvis and low back.   In this article, my focus will be on protecting the sacroiliac joints (SI).  These joints connect your spine to your pelvis and are especially vulnerable in a twist.

Ring of bones

It helps to understand anatomy and kinesiology so you can feel what is happening in your own body and effectively make adjustments.   The SI joints are located at the base of your spine on each side where the top of the sacrum (end of our spine) wedges between the two pelvic bones (innominate).  The joint in the front of the pelvis where the innominate bones meet is called the pubic symphysis.  These three joints form a ring of bones that act as a unit and are also shock absorbers transmitting the effect of our weight and gravity through our hips.  If the integrity of any of these joints is affected (too rigid or too loose), the entire ring may become dysfunctional.

Normal movement of the sacrum in relation to the innominates is described as nutation and counternutation.  No need to memorize these terms, but know that you can control the direction of movement in your pelvis and essentially your sacrum.  For instance, by arching your back you move the front of the pelvis and the top of the sacrum forward (nutation) and by flattening the back you move the front of the pelvis up and the top of the sacrum back (counternutation).

What should happen during a seated twist?

When you twist, the entire ring of bones should turn with you.   For example, when twisting to the right, the left innominate or pelvic bone rotates anteriorly relative to the right and the sacrum rotates in the same direction as the turn.  To understand anterior rotation, place both hands on their respective pelvic bones then arch your back.  You will feel the front of your innominate on both sides tip anteriorly or forward. If you attempt to tip just one side forward (left) it will naturally cause your spine to rotate the opposite direction (right).  To visualize this motion in the sacrum hold your right hand up palm facing away.  Tilt the hand so that the thumb side moves further away.  This is right sacral rotation.  The left innominate rotates anteriorly and the top left side of the sacrum will move forward (nutate) slightly more than the right side to make this happen.  Preventing this natural movement from occurring can potentially strain the low back and SI joint.

Is letting this natural movement occur enough to protect your low back and SI joints?   What prevents you from twisting too far?

Utilizing muscle energy to stay safe in your practice

It is difficult to control a twist (and where the most motion occurs) if you focus only on turning your upper body and allow the lower body to passively follow.  You may notice that regardless of whether your ground through your sit bones or not,  the crux of the twist seems to be in the lower back or SI joint (not desireable).  If you know what your body wants to do naturally (move with the turn), you can then use muscle co activation (working agonist and antagonistic muscles simultaneously) in a twist to gain stability.  You will feel like you enhance the effects of a twist by moving from the bottom up and from the top down simultaneously.   Below are a few tips for applying this concept in seated twists.  For the sake of simplicity I will discuss parivrtta sukhasana pose or the easy seated twist pose.

  1. Sit up tall with your legs crossed.  Use a folded blanket if needed so that you maintain a straight spine.
  2. Bring your left hand to your right knee and your right hand beside your right hip or slightly behind you.
  3. Begin to turn the navel to the right.  Avoid using your arms to pull you.   Notice that the left innominate will rotate anteriorly and the right posteriorly.   Actively attempt to do the opposite, move the right innominate anteriorly and the left posteriorly while still gently moving the navel to the right.  This action will result in co activating muscle groups to stabilize the pelvis while controlling the twist.
  4. While in the pose, twisting to the right, begin to turn the navel to the left as you twist to the right.  This action enhances the effect of step 3.
  5. Gently press the outsides of the feet into the floor.  This activates the gluteal muscles further stabilizing the pelvis.
  6. Breathe naturally throughout the motion.  Don’t attempt to pull in the belly as this could affect your ability to turn and create strain.

If you experience and discomfort after following these tips, it is likely there is some level of dysfunction.  Consider consulting a physical therapist or a qualified movement specialist to help determine what’s limiting you.  Otherwise, twist away!  Your spine will thank you for it.

I hope you found this blog helpful.  Please share your experiences!  I’d love to hear from you.