Sacroiliac Joint Injections

In this type of injection, medication is injected into the sacroiliac joint (SIJ).  This less known but important large joint is located in the sacrum approximately at the junction of the lower back and the upper buttocks. The human body has two sacroiliac joints, one on the left and one on the right, that often match each other but are highly variable from person to person. Pain from the SIJ can result from arthritis and various SIJ dysfunctions and can be felt in the lower back and buttocks. Pain from there can also refer to the hips, groin, and even down the legs. SIJ injections can help alleviate and even stop this pain. 

What is being injected?

Commonly the medication injected is usually a steroid (dexamethasone, depomedrol, kenalog, etc), often mixed with an anesthetic (such as lidocaine or marcaine).  In cases of diagnostic SIJ injections the injected medication may be an anesthetic alone without steroid, and the main purpose is to rule in or rule out the SIJ as the pain generator. 

What it does

Helps reduce pain and inflammation from the SIJ. Like other joints in the body SIJs are covered by a joint capsule, lined by cartilage and have joint fluid inside. Arthritis as well as dysfunctional movement can result in pain. The injection helps reduce the inflammation and pain. Due to the numbing medicine (the anesthetic) included in the injection, there may be temporary pain relief afterwards that may last several hours. Once the numbing medicine wears off, however, the pain will most likely return until the steroid medication starts to work (usually after 24-48 hours).

What it doesn’t do

SIJ injections (with steroid and/or anesthetic) do not repair or cure SIJ arthritis, dysfunction, nor any other kind of injury. Nor do they promote healing of any tissue.  In that sense the SIJ injections do not “fix the problem.” They also do not have any way of preventing pain from returning in the future. They are strictly meant for alleviating pain. Pain relief is usually short term (estimated average is 3-4 months).

Then why do it?

Usually recommended when pain is very severe, uncontrolled by medications, unable to tolerate exercise or physical therapy, and when surgery could be avoided or not indicated. SIJ injections allow quick resolution of pain for a period of time during which with proper diagnosis and exercise based therapy the SIJ dysfunction may resolve on its own and this is why the pain may not return. Not because the injection “cured” the problem but because the injury process has run it course and any dysfunctional movement or gliding of the SIJ was corrected. Unfortunately in cases of severe dysfunction or arthritis the pain may continue to return and may need to be managed.

What are the risks?

Overall considered safe when performed with fluoroscopic (xray) guidance by a physician specialized in interventional pain management. Preferably one who is  board certified and fellowship trained.  Risks include infection, bleeding, allergic reaction, pain aggravation. As this injection is not near the spinal cord nor any major nerve, if done accurately risks of nerve injury and paralysis should not exist.