What a fascinating world that of the sacro-iliac is! The ligaments that run from the sacrum to the ilium – like the guywires of a suspension bridge – need appropriate span and tautness to be healthy. Sitting down all day compresses the SI joint and results in overly lax ligaments. Then any stray force – just leaning over and twisting a little – can sprain some of the ligamentous fibers.
Also this is the transitional joint from the axial to the appendicular system. The axial system is in a sense who we are and the appendicular can be viewed as how we interact with the world around us. So the SI emobodies the interface of our being and our doing. As with the ligaments, if there is appropriate span here, then you experience some critically important breathing room between your being and your doing.
The part of the ilium (the uppermost bone of the pelvis) to which the sacroiliac ligaments attach is called, poetically, the ala – which means “wings”. Just as your scapula are the “wings” of your upper extremity, the ala are the wings of your lower extremity. However, how often do you feel the winged character of your pelvis? When you work clearly with the soft tissues, bones, and joints of the sacro-iliac, you free the ala of the ilia. The low back and sacrum can then become a positive source of pleasure and health in your life!