Pain that manifests as a result of psoas major muscle dysfunction can take all forms. In today’s post we will look at lower back pain. The lower back or lumbar spine is five bones that make up the portion of the spinal column between the pelvis and the rib cage. Whereas the pelvis and ribcage have a bony presence from one side of the body to the other—in between these two structures there are only five bones, the largest five bones of the spine, living directly in the center of the body. These five bones, whose tiny inward curve determines our ability to be upright successfully, require a great deal of muscle tone to live in the proper alignment.
The psoas major muscle pulls the bones of the lumbar spine forward when it engages or shortens. If you sit down into a chair as soon as you stick your butt out and send the thighs backwards towards the seat the psoas moves backwards at its base (the inner thigh) and draws forward and down at its top pulling the lower back forward with it. Hopefully, this is fairly easy to feel.
With this action there is meant to be an opposite reaction. When the psoas major muscle pulls the lumbar vertebrae forward the muscles of the spine— the erector spinea, the multifidus— are all supposed to lengthen up the back, extending the spine, against the downward pull of the psoas major. This is a concept called reciprocal inhibition.
Ideally the psoas works like a pulley system in the body helping to hoist the spine up on top of the the pelvis but when this doesn’t happen as planned—which is often—due to poor posture and chronically tight muscles, the psoas pulls the lumbar vertebrae forward but the spinal extensors can’t provide the opposite lift up. As a result the bones of the lower back compress causing lower back pain in the center of the spine.
There is good pain and there is bad pain. Pain in the joints is almost always bad pain, especially in the joints of the lumbar spine. Dysfunction in the psoas major muscle can manifest in many different forms of pain but this particular lower back pain that is felt in the joints of the lumbar spine requires a lot of skeletal and muscular realignment.