WHAT IS IT?
The SI joint, or the sacroiliac joint, is the joint of the pelvis located in the buttock region. This joint is a common source of back pain. To diagnose that the pain is coming from this area, the physician will inject a combination of local anesthetic and an anti-inflammatory (corticosteroid) into the joint, and if the patient experiences pain relief within a few minutes from the local anesthetic, we can conclude that the source of the pain is the SI joint. The anti-inflammatory portion of the injection takes about 2-3 days to become effective, but can last for quite a while, even up to a few months.
WHAT ARE THE RISKS?
There is some risk of infection and bleeding.