A Sacroiliac Joint (SI) Injection is an injection of local anesthetic and a steroid medication into the sacroiliac joint. Due to the numbing medicine used during this procedure, you may experience temporary pain relief afterwards that may last several hours. The steroid medication may give longer lasting pain relief and usually begins working after 24-48 hours. SI joint injections are used for both diagnostic and therapeutic purposes. The SI joint injection enables physicians to confirm that SI joint damage or irritation is the cause of your symptoms.
SI joint injections are commonly used to treat pain in the lower back, buttocks, groin, and leg due to injury or inflammation of the SI joint. The SI joint connects the pelvic bones to the spine and does not move very much. Due to this, the joint commonly absorbs large amounts of forces from the upper body, which is why it is a common cause of pain.
The procedure will be performed with you lying on your stomach. Your injection site is cleansed with an antiseptic soap and alcohol, and then covered by sterile drapes. The skin is numbed with local anesthetic (numbing medicine). Using X-ray guidance, a needle is advanced into the sacroiliac joint. X-ray dye will be injected to confirm proper placement. Local anesthetic (numbing medicine) and steroid are then injected into the joint.