The word 'syndrome' refers to a disorder or disease in which the cause cannot be specified. SI joint pain syndrome is also a collective term for symptoms that occur around the SI joint, and it is difficult to say that the SI joint itself is an actual source of pain.

Although it is not directly relevant, compelling evidence shows 70% of ordinary people do not have pain even if there is bulging disk (lower back) or labral tear (hip) in their MRI results. Therefore, it is highly likely that the structure (SI joint) itself is not the culprit for SI joint pain.

Rather, the more scientifically grounded cause of pain is muscle tension and the resulting friction between muscles and/or tendons. If you look at the image above, the SI joint is the place where the most important muscles in the back of the body, such as the glutes and erector spinae, are attached. Hence why problems can easily occur if you do not have the right balance of strength/tension between these muscles.

Let me give you two examples.

What if the pelvis rotates to the left in the above picture? Then, the left hip is likely to fall back and this puts the left glutes and erector spinae muscles in a lengthened position. These muscles will not elongate endlessly but rather will try to tighten up to prevent further pelvic rotation to the right. As a result, tight glutes create a pulling force on the ilium(pelvic bone), while tight erector spinae gives the sacrum (near the tailbone) an upwards pulling force, which can cause more stress on the SI joint.

Also, what would happen on the right SI joint if the right pelvis tilts backward (posterior tilt)? Posterior tilt itself tends to pull the ilium and sacrum apart. In addition, the right ilium that is being posteriorly tilted will press on the right piriformis. Then, the muscle is likely to be stressed and sensitive. Sensitive piriformis can also cause pain and this can be misinterpreted as 'SIJ pain'.

To conclude, it is not advisable to specify the SI joint itself as the main cause of pain. In a broad sense, improving muscle balance/tension around the SI joint is the key to a full recovery, which will be focused in this program.