The sacroiliac joint is a junction in the pelvis where the sacrum and ileum join. This connection has a fine covering of cartilage that protects both bones. The rough texture of each bone’s surface allows them to interlink and provide motion at the point of contact. The sacroiliac is a synovial joint, which means that a lubricating liquid called synovial fluid occupies the space between the bones, allowing some joint movement. The synovial fluid functions similar to oil on a squeaky door hinge, reducing friction and bone deterioration.
The sacroiliac joint’s purpose is to balance and transfer weight between the legs and the upper body with activity such as walking and act as a cushion to help manage force transfer from the spine to the pelvis. Because of this, the joint’s linkage allows both bones to slide against each other in several directions but is limited in the overall range of motion to help reduce the risk of dislocation. In women, the sacroiliac joint becomes more flexible during pregnancy in preparation for childbirth.
The most common injuries and conditions affecting the sacroiliac joint include:
A physician will use a physical exam with specific functional tests to diagnose sacroiliac joint problems. An MRI or a sacroiliac joint block injection may be valuable in pinpointing the location producing the symptoms. Treatment may be initiated with conservative measures such as ice, heat, pain medications, and physical therapy or chiropractic manipulation once the pain is adequately controlled. If problems persist for several weeks or more, a surgical procedure called an SI joint fusion can be discussed.
If you have experienced SI joint problems and would like to learn about our treatment choices from one of our specialists, please contact our Seguin or New Braunfels offices.