Mastering the Basics: SI Joint Safety in Twists

In a recent post, we looked at how the SI joint is designed to move, and what types of movements can damage the joint over time.  In this post, we will look more closely at seated twists, some primary culprits (if done incorrectly) of SI joint pain.  The more traditional approach to seated twists is to root the sitting bones, keeping the pelvis stationary as the spine rotates.  However, some very well-respected teachers favour a movement of the pelvis with the spine, which can alleviate the SI joint pain sometimes felt in twists.  Which is right?  It's not so much a question or "right" or "wrong"; it's finding that magical intersection of maximum safety and greatest benefit, the "sweet spot" we are always seeking in Purna Yoga asana.  

For all this to make complete sense (i.e., so you can practice and teach it effectively),  first

Begin by reviewing how your SI joint works >>

Seriously, review this information; it only takes 10 minutes and will greatly deepen your understanding of the mechanics underlying this topic. 

SI joint, front and back view.png
SI joint, front and back view (1).png

The sacrum and ilium (hip) bones are designed to move together; SI joint problems often originate from encouraging an independent movement of the sacrum inside the joint over an extended period of time.  This weakens the support structure of the joint, and, depending on the original stability of the joint (we're all different!), can sooner or later result in misalignment of the joint.  Your body informs you of this misalignment through pain.  In twists, specifically, independent sacral movement can occur when the practitioner roots the sitting bones and then takes the twist down into the sacrum, encouraging the sacrum to twist inside the joint while the hip bones are fixed.  

So, on one level, it does make sense to release the sitting bones, so the pelvis flows into the twist and releases the torque in the SI joint.  Many people who experience SI joint pain in seated twists feel immediate relief when they release the rootedness of their sitting bones, so I understand why some have converted to this method.  

Is this the method we espouse in Purna Yoga?  No, it's not, because by unrooting your sitting bones and allowing the pelvis to flow with the twist, all you are actually doing is lessening the twist (because the pelvis is moving in the same direction as the spine).  It may decrease pain by relieving some torque in the SI joint, but it also makes your twist less effective.  (You can get the same result just by backing off on the twist in the lumbar without moving the pelvis.) That's just a halfway solution: we want the twist to be completely safe, and fully effective.  All that takes is proper twist technique, starting with the mantra: 


(To understand where this information comes from, check out the Purna Yoga asana lineage >>)


How to Twist Safely

All twists essentially boil down to three actions:

  1. ROOT
  2. LIFT
  3. TWIST

It's the third element, the twist, that you need to focus on to keep your SI joint safe (the root and the lift keep the lumbar, thoracic and cervical spines safe, but that's another post).  Specifically, you need to know where to initiate your twist:

All twists must start above the sacrum.

Twists, properly done, begin at L5/S1 and move up the spine. If you feel pain in your SI joint when you twist, you know you are twisting below this spot, drawing the sacrum into the twist, and creating torque in the SI joint.  


By starting the twist in the correct spot, you leave the sacrum out of the twist altogether.  You therefore do not encourage independent movement of the sacrum  (no torque), AND you get a full, deep twist. The twist is safe and effective: the best of both worlds.  For this refinement to happen, you have to move to a deeper level of awareness (which is when things really start to get interesting in asana).  You must split your mind, with one part of it in your pelvis and sacrum, holding them stable and unmoving, and another part in your spine, revolving it upward from L5 to C1 (where the skull rests on the neck).

 Iyengar in Marichyasana I

Iyengar in Marichyasana I

Here's how a basic seated twist like Marichyasana I would work:

  1. Root the sitting bones, back of the left (extended) leg and heel, and the right heel
  2. Lift the pit of the abdomen and side waists to lengthen the spine
  3. Starting above the sacrum, twist your spine to the left


To find L5/S1, palpate.  Follow your spine downward until you feel the wide flatness of your sacrum, and then zero in on the top edge as best you can.  (Your yoga teacher, massage therapist or chiropractor should be able to help you.)  You can also trace the back rim of your pelvis, moving towards the spine.  When you get near the spine, you should feel the PSIS (posterior superior iliac spine) as two bumps, one on either side of the spine.  (They are more or less hard to find depending on your ratio of boniness to voluptuousness.) The PSIS are close to the level of L5/S1.  

If that's too difficult, or if you are leading a class and don't want to take time to palpate, just start the twist above the hips.  That's technically a vertebra or two higher than L5/S1, but that's by far preferable to torquing the SI joint.

Now, let's add another principle that may, at first, sound contradictory:

While you should root the sitting bones, you should not prevent them from moving if they need to.

Again, ALWAYS start your twist above the sacrum.  But, if through zeal or momentary lack of focus you accidentally take your twist down into your sacrum, movement of the pelvis is your safety valve; it releases torque and prevents the action of the twist from going into the SI joint.  So, it is imperative that you not align the foundation of your twist in a way that prevents the pelvis from moving if it really needs to.  

For example, in Marichyasana I, if you draw your right leg in, placing your heel directly in front of your right sitting bone or wider (as in the first photo), and then twist to the left, the right side of your pelvis cannot move forward if you inadvertently take your twist down into your sacrum -- the right foot is blocking movement of the outer hip. 


If the outer hip can't move forward and the twist goes below the magic L5/S1 starting point, then the torque has nowhere to go other than the SI joint.  As explained in my prior post, this will destabilize the joint over time, and then create misalignment and pain.  Again, that timeline is body-specific; if your SI joint tends to be unstable already, it can happen with the first twist.  If you have a very strong and stable SI joint, you may get away with poor twisting technique for life.  But that's not a gamble worth taking.

A better option (in addition to refining your twist technique) is to draw the leg in and place the right inner ankle against the right inner thigh (as in the second photo), so the outer hip can flow forward if it must.  Movement of the pelvis is neither the goal nor the best practice, but it is a useful safety valve to release the SI joint torque that can happen with poor twisting technique, so don't do anything that prevents it.  In summary:

1.  Root your sitting bones.

2.  Always start your twist above your sacrum.

3.  Maintain your safety valve: don't prevent the pelvis from moving if it absolutely needs to.

A Final Observation

Never do anything that creates pain in your joints.  If you have an unstable SI joint, twists might be problematic even when following best practices (and some twists exacerbate the problem more than others).  Find a good therapeutics practitioner (of course I recommend a Purna Yoga teacher) and work to create alignment and stability of the joint.  Then move back into twists with heightened awareness of refined twist mechanics.  Your teacher should be able to instruct you as to which twists impact the SI joint most and least, and give you refinements for keeping your SI joint stable in twists.

Happy twisting!

Want to learn more about safe mechanics in asana?  

Join Purna Yoga College in Pondicherry, India from January 10 through February 8, 2018.  All of this SI joint information, and a WHOLE lot more, is in our 200-hour program.  You will learn to practice and teach authentic yoga in the place of its birth.

Other locations for the program >>