What Is SI Joint Pain? Injury, pregnancy, or uneven movement in your pelvis can cause low back, butt, and leg pain that's often worse after you've been sitting for a while. This may be because ...

Your SI joint, or sacroiliac joint, connects your sacrum (otherwise known as the tailbone) and your illiac, the bone of the topside of your pelvis. Technically, there's two of these joints—one on ...

The SI joint is where the tailbone (sacrum) connects with the back of the pelvis (ilium). Issues in this area can cause pain ...

The presence or absence of chronic sacroiliitis is a key clue in diagnosing inflammatory back pain and is often seen in axial spondyloarthritis and other rheumatic and nonrheumatic ...