Part 1 - What is the Sacroiliac Joint Syndrome?

It is a typical complaint in our field of therapy: “My back hurts all the time.” While sources of back pain are numerous, Sacroiliac Joint Syndrome is a major source of hip and back pain that is difficult for physicians to diagnose and treat.

The sacroiliac (SI) joint is a relatively immobile joint made up at the sacrum (base of the spine), ligaments (adhesions connecting bone to bone) and the ilium (the pelvic crests). Chronic postural stresses or acute injuries may stretch or weaken the ligament structures which hold the joint intact.

By focusing on the anatomy and biomechanics of the sacroiliac joint using Active Isolated Stretching (AIS), we hopefully will dispel some of the mystery of treating SIJS. Most of us don’t think of the sacroiliac joint as a true joint like the knee or elbow because we don’t “see” it working like we see the external joints. It is however, an important joint of the pelvis.

There are many supporting structures of the SIJ that help maintain the biomechanical actions of this joint. These include ligaments and muscles that blend with the fibers of the SIJ capsule, much like the ligaments of the hip and shoulder.

Biomechanically, the pelvic girdle forms a steady connection between the spine and lower extremity, or it should if the posture is healthy. Nature fused the sacral vertebrae into one bone (the sacrum) to provide more stability, and also increase the attachment site for the gluteus maximus muscle, the largest muscle of the body.

Now that we have a better understanding of the anatomy and biomechanics of the sacroiliac joint, next time we will look at causes of sacroiliac joint syndrome and subsequent treatments using Active Isolated Stretching (AIS).

Useful links:

Part 2: Treating SIJS...

Understanding Back pain...