SI joint injections are performed with the assistance of X-ray guidance. A contrast dye is injected once the needle is in place so that your doctor can see that the medication is spreading the way that it should.
For a diagnostic SI joint injection, a numbing medication is injected into the joint. Your doctor will then ask you to perform the movements that normally cause you pain. If you find that your pain is reduced or eliminated after the injection, this can lead to a diagnosis of sacroiliac joint dysfunction. More than one diagnostic injection may be performed to confirm the diagnosis.
The procedure is the same for a therapeutic injection. However, a steroid is also injected along with the pain medication to provide relief from both pain and inflammation. Many people who have therapeutic SI joint injections experience immediate relief after the procedure. Your doctor may have you start physical therapy after you have had an injection in order to achieve a better range of movement and to help prevent a reoccurrence of your SI joint pain. If pain returns, you can have SI joint injections up to three times a year.
After the procedure, you may experience some weakness or numbness in the legs. This is temporary and is related to the anesthesia. Some people also experience a temporary increase in SI joint pain that goes away after a few days. Tenderness at the injection site is not uncommon; if this occurs, an ice pack can provide relief.