Potential Causes of SI-Related Pain: Sacroiliac / SI Joints Anatomy, Pain & Issues

Pain from SI joint stress is generally caused by the pelvis and sacrum moving in opposite directions, which could happen for such reasons as:
- Postural imbalance
- An accident or sudden movement, including a too-strong yoga adjustment
- Loose ligaments allowing joint hypermobility
SI pain may also be a sign of a sensitized nervous system, a defining characteristic of chronic pain, which we cover in-depth here.
Pelvis & Sacrum Moving in Opposite Directions
SI pain is a result of stress at the joint created by moving the pelvis and the sacrum in opposite directions. This can be caused by an accident or a sudden movement, as well as poor standing, sitting, and sleeping habits. In yoga asanas, inflammation and/or pain mainly arises due to the unusual and consistent stresses experienced by the supporting ligaments and muscles around the SI joint. This is especially true in asanas that move the pelvis and sacrum in opposite directions (twists or forward bends with legs wide apart as in Parivrtta Janu Sirsasana or Upavistha Konasana). – Ram Rao MD
Acute vs Chronic Pain
In contrast to… short-term pain associated with acute injury, when someone’s SI joint pain is more long-term or chronic in nature… it’s… likely that the person’s nervous system is… sensitive around that spot. – Jenni Rawlings