Sacroiliac joints (SI joint) are joints in the lower back region, located where the sacrum and ilium bones conjoin. Even though these joints are small and have limited motion, they have an important role of connecting your spine to the pelvic bone and thus the lower part of your body. They perform important functions by absorbing the injurious shock forces of the upper portion of the body. Any inflammation or irritation in SI joints may cause pain in the lower back, abdomen, groin, buttocks or legs.
Sacroiliac joint injections can be used both for diagnostic as well as therapeutic purposes. As a diagnostic tool, it helps your doctor locate the origin of pain. To diagnose SI joint pain, an anesthetic injection is given to the joint under X-ray guidance. An acute relief in low back pain following the injection indicates an abnormality in SI joint. For therapeutic uses, SI joint injections will contain a steroid medication along with an anesthetic agent to provide relief from pain for a longer duration. When steroid medication is injected into the painful & inflamed joint, the inflammation reduces and thus relieves the pain.
You will have an intravenous catheter placed in your arm before the procedure begins. The catheter is to provide medications if necessary during the procedure. You will be lying on your stomach and the area where the needle is to be inserted near the SI joint is numbed with a local anesthetic injection. Then your doctor will advance the needle under the fluoroscopic guidance. Once the needle is in the right position the medication is injected.
Risks and Complications
Complications are very rare but do occur. Possible complications after SI joint injections include allergic reaction, infection, and increased pain.