Scoliosis, the term used to describe an excessive curvature of the spine, may have its genesis in a tight psoas muscle. Everyone is dominant on one side of the body and it is not likely that any body’s spine is completely straight, but the term scoliosis is applied when the curvature of the spine is greater than 10 degrees.
Scoliosis can occur at a number of times during someone’s life. Sometimes the curvature of the spine can be congenital and the condition presents itself at birth. There are certain conditions that are often coupled with scoliosis such as spina bifida or cerebral palsy.
Most often the exact cause is not known and the excessive curvature presents itself anywhere from infancy to adolescence to adulthood. In these cases I have no problem ascribing a neuromuscular issue to the curvature in the spine which is where the psoas comes in.
The psoas muscle connects the legs to the lower spine and the classic indicators of a tight psoas are often similar to the way that the curvature of the spine is diagnosed—one shoulder higher or lower than the other; one hip higher or lower than the other; and leg length discrepancy.
A tight psoas can seriously mess with the spine and pelvis. If the portion of the psoas that attaches to the leg is tight is can increase the curve of the lumbar spine. If the upper end of the psoas is tight it can decrease the curve.
The body always compensates in some way for muscular imbalances. If one side of the body is tight and not working all that effectively, the other side with often work harder to make up. This can effectively pull the spine in two directions.
The curvature of the spine can take on many patterns. The tight psoas can pull the lumbar vertebrae forward on one side which can begin the curving process. Anytime the spine is pulled in one direction there will be compensating forces moving in another direction.
Invariable the rib cage with get involved and depending upon the circumstances the entire spine up through the neck can get twisted in the scoliotic journey.