By Richard DonTigney
The lack of movement in the sacroiliac joint is a myth. When walking the pelvis moves obliquely to the line of travel, to increase the length of the stride. The sacrum moves on the asymmetric pelvis to drive counter rotation of the trunk to decrease loading forces. Pelvic dynamics has profound effects on normal gait.
The joint is vulnerable to injury through minor trauma only in anterior rotation of the innominates on the sacrum. Idiopathic low back pain is a commonly overlooked, reversible dysfunction in anterior rotation, usually bilateral. A diagnosis of dysfunction can be made simply by identifying a single painful point at the posterior inferior iliac spine that is caused by a vertical shear on the conjoint origin of the piriformis muscle and tearing of the capsule at S3. See pain patterns here. The anterior rotation will loosen the iliolumbar ligaments, destabilize L4,5-S1 and increase shear and torsion shear to the disks. Correction restores stability.
Full correction in posterior rotation will provide immediate relief of pain. More than three treatments are seldom necessary. Stabilization of the unstable SIJ can be obtained with five to six sessions of prolo specifically to the long posterior sacroiliac ligaments. Prolo to the iliolumbar ligaments without correction of the SIJ first can tighten the joint in the uncorrected position and may prevent correction.
Anyone not properly treating dysfunction of the sacroiliac joint is perpetuating chronic low back pain. X-rays of innominate movement on the sacrum are published on-line at www.thelowback.com/how.htm#movement
