Did someone say piriformis? · Mollie McClelland Morris · Yoga

Did someone say piriformis?

Piriformis muscle in yoga

Of the many mysterious muscles that get thrown about in yoga, the piriformis is one that is a huge source of confusion (perhaps almost as much as the psoas). This vital muscle is used for stabilising the sacroiliac  (SI) joint, and is very close to the sciatic nerve, so can affect the functioning, and pain, in either of those areas. It is important for posture and walking, and has potential to become tight in people like yogis and especially dancers. But you have to remember this:

All muscles are vital (or we wouldn’t have them). So working with the piriformis is important, but we have to work it in a balanced fashion with our whole body. If you want a refresher about muscles and how they work, read this.

What is the piriformis muscle?

The piriformis is a muscle that connects sacrum to the greater trocanter. You can find it an feel it like this:

  • Put on hand on your outer thigh. It is usually quite firm.
  • Slide up that firm surface, until you feel a bone that sticks out to the side. This is the greater trocanter: top of your thigh bone, but is not your hip joint.
  • The greater trocanter is big and knobby, but is not the round ball at the top of the femur (that is inside the hip joint). If you don’t know where your hip joint is watch this.

Rub the greater trocanter a few times. It feels nice, and can help your posture.

The origin of the pirifomis is on the anterior (front) surface of the sacrum, meaning it is inside the body. But you can touch near here.

  • Find your tailbone, then move up onto the sacrum, and a little out to the side. The muscle on the outside is the gluteus maximus, but beneath it is the piriformis.
  • If you move about 2 fingers outside the lateral (side) edge of the sacrum and rub, it can be quite tender. That is the belly of the piriformis muscle.

What does the piriformis do?

The piriformis is an external rotator, meaning it brings the greater trocanter towards the sacrum, which rotates the femur out. Touch the 2 points you found above, the greater trocanter and the sacrum, and try to move them towards each other. It can help if you have slippery socks on to feel the leg externally rotate.

Some of these dance moves can help you see the movement of the legs that the piriformis participates in.


The piriformis attaches to the sacrum near its axis of rotation. That means that it helps with counter nutating the sacrum (“tucking the tailbone”) but because it is near the axis of rotation, it doesn’t provide a lot of force for this. Mostly, it helps stabilise the sacroiliac joint when it is in that position.

Why is the piriformis muscle important?

The sciatic nerve runs near, or even through the piriformis. So when it is tight or inflamed, it can put pressure on the sciatic nerve and cause pain.

Why does it get tight?

The turned out position that dancers use is the shortened position of the piriformis. So standing like this can cause the muscle to tighten and shorten.

For the rest of us, a tucked tailbone position, puts strain on the piriformis, because the SI joint is not intrinsically stable in this position, and therefore needs force – muscle power – to help stay closed. The piriformis is providing that force, so it can get tight doing this job.

If your ordinary posture is standing with more weight on one leg – especially if you “lean one hip out” when you stand like this, it is likely that the piriformis is extra tight on one side. You might have SI joint pain on one side, because of this imbalance.

How can you relieve pain or tightness in the piriformis?

The most important thing to do is to free the movement of the sacroiliac joint, but allowing the movement to happen as it should.

For me, the first step is to practice standing on the femur heads. That means find your hip joints (you haven’t watched this video yet, have you?) and then play with balancing the pelvis over them (side to side and front and back).

If you have been practicing these movements in ordinary posture:

  • tuck tailbone
  • squeeze your bum
  • tighten pelvic floor
  • suck belly in and up

STOP THEM IMMEDIATELY! Give your bum a shake, wiggle and tap. Rub your belly and take a few deep breaths.

Take a little walk and check in whether these movement cues are part of your habit patterns (around your room is fine).

Step Two. Using fists or rubber balls, tap the bum, from the sacrum to the greater trocanter. While you do this, move around, Stand on one leg or the other. Internally or externally rotate the legs. Flex and extend at the hip joint (bend forward and lean back). Lean your hips side to side, and hike one hip up and down.

Step Three. Embody function. Touch the origin and insertion of the muscle. Then externally and internally rotate the leg, feeling (and even saying to yourself) piriformis lengthening, piriformis shortening. 6-10 times is usually good. Compare that leg to your other leg. The next version is to stick your bum diagonally out to the back, imagining you are leaning into the piriformis muscle like an elastic rope (like the ropes around a boxing ring). Feel the elasticity of the muscle push your pelvis back to the centre. 6-10 times is good.(I usually repeat this mini sequences twice). Feel for change.

Piriformis Muscle in Yoga

As with every muscle,if you focus on tightening the piriformis muscle in yoga practice, you won’t improve its function. Instead, we want to balance out its function, and allow it to stretch when needed, release when needed, and engage when needed for support and positioning.

In yoga, we often think of stretching the piriformis, which can feel nice. I like to explore releasing the muscle, which can be done in a supine spinal twist. As the top leg crosses he body, the piriformis is in a long position. You can either work with this as an active stretch, or add some support, so the muscle stays in a long position, without being loaded. A block, bolster, pillow or rolled up towel can be a good support under the leg in a spinal twist to facilitate release.