Ok. Here are some really great diagrams I’ve found across the web which should help simplify some of the things I’m talking about.
These graphics were all available under a Creative Commons license — thank you so much to those who made them available! I’ve linked to the source below each illustration.
First, let’s start with some larger areas of the body. These are all relevant areas when it comes to having SI joint-related pain.
The Lumbar Spine:
The Hip Bones:
The Sacroiliac Joint is located at the junction of the sacrum and the hip bones: