Psoas? So What?!

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Psoas What

What is the Psoas?

This powerful muscle pronounced SO-AS, is a deep major muscle connecting the upper body to the lower body. It is s comprised of deep and superficial layers that begin at the 12th Thoracic vertebrae and finally attaches on the inside of the femur. The psoas attaches directly to 22 of the spine’s disks!

What does this amazing muscle do?psoas-1

Tests reveal that during sit-ups the psoas simultaneously extends the upper vertebrae, while flexing the lower vertebrae and hips. Studies show that the psoas has an active role in hip flexion but has a larger role in stabilizing the spine. It is extremely important that the psoas is lengthened to allow the spine, pelvis and hips to move naturally for a pain-free and injury-free body.

Psoas Imbalance: A Physiological Explanation

psoas-2We commonly see clients whose spinal erector muscles (long muscles along the spine) are stronger on the right than on the left. This imbalance causes a rotation of the spine and shearing effect. The Psoas on the left front side may respond by shortening and splinting (which tends to make a muscle weaker) See Fig. 1.

This causes the front-left side of the body to have a short and tight muscle and the back-right side muscle is short and tight! This imbalance can lead to injury or pain.

Why are Psoas problems common for people in our society?

These are the main actives that tend to get people in this situation:

  • Driving
  • Asymmetrical sports
  • Sitting at a desk all day
  • Sitting at home

“What do I do?”

This is where many health practitioners and clients tend to get fixated on one muscle. Almost weekly there is someone who comes into the clinic blaming their hip pain, back pain, or Sacroilliac joint pain on the Psoas. Let’s set the record straight. It is never one muscle! This is because of muscle coordination also known as kinetic chain function. When one muscle contracts another muscle has to extend and when those muscles are contracting muscles elsewhere in the body have to stabilize so muscles can do their job.

psoas-3The psoas and spinal erectors cannot function properly if the hip stabilizers are not working properly. Literally every person that we have worked with at the clinic has asymmetrical patterns in their hips. This is the base of the spine, with muscles like the glutes and deep rotators helping to stabilize the sacrum (base of the spine) and help the ilium attach correctly to the sacrum. With out these muscles working in proper relationship with the psoas and spinal erectors the spine feels “insecure” or “unstable” because there is nothing under it to help it work.

Think of when you were a kid and you tried to balance that broom with the palm of your hand. The psoas-4pelvis would be the palm of the hand and the broom would be the spine see fig 2. If you tilt the pelvis (or hand) forward the broom head drops back towards your head and if you tilt the pelvis (hand) towards you the broom head goes away from the head. This broom handle analogy is a simplification and has no where near the dynamics of the spine but the spine is still at the mercy of the laws of physics.

Where did my hip muscles go?

Sitting is a position that is over done in our society. Here is one very good reason not to sit for very long! When sitting on your Glutes and deep hip rotators of your butt, it literally squeezes the blood out of the muscles just as if you sat down on a sponge filled with water – all the water would disperse. Now this does not happen right away. You know how your butt feels when you have been sitting for long periods of time? This starts to choke and atrophy these muscle groups, making them weak and useless. Thats when those spinal erectors and psoas start to rotate and splint to try to keep your spine upright. Now multiply this by years and you have some dysfunctional hips and spine. This can lead to disc problems, joint cartilage problems, loose ligaments in hips and low back, etc.

What can I do to keep my Psoas and Hips working? Stand as much as you can. Get outside and move your body. These asymmetrical patterns can be tricky and tough to change but with patience and persistence you can re-balance your body. Get a standing desk, take a yoga class, get a personal trainer, get massage, get posture therapy, go for walk in the woods with friends. There are many places that you can start. Remember to take it slow, try not to over exert yourself, be kind to your body.


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