The goal of the sacroiliac joint injection is to reduce pain and inflammation in the sacroiliac joint, which is located in the lower back where the spine meets the pelvis. This minimally invasive procedure consists of injecting a small amount of numbing medication (local anesthetic) and steroid medication under fluoroscopic (x-ray) guidance to ensure accurate placement of the needle in the joint. The injection can be carried out as a diagnostic tool to determine whether the sacroiliac articulation is the root of the patient’s pain, or as a therapeutic treatment to diminish pain and inflammation in the joint. The procedure typically takes only a few minutes and is performed on an outpatient basis. After the injection, the patient may experience pain relief and improved function for several weeks to several months.