Sacroiliac Joint Injections For Pain Relief

The sacroiliac (SI) joints are formed by the fusion of the sacrum and the right and left iliac bones. The two sacroiliac joints, which are small in size, frequently match each other, but are extremely variable from person to person. Sacroiliac joint injections (AKA SI joint injections), are designed to help relieve lower back, leg, and groin pain. There are two different types of injections currently available:

• Number 1: Diagnostic SI joint injections which enable your Pain Specialist to understand whether your pain and inflammation is coming from your SI joint.

• Number 2: Therapeutic SI joint injections, which work to relieve your Sacroiliac joint pain for a limited amount of time.

Now let’s examine these two procedures in more detail:

Number 1

In the case of Number 1 (Diagnostic SI joint injections), this will only be administered if your Pain Specialist feels that your lower back symptoms are emanating from your SI joints. Prior to giving an injection, he/she will stress your Sacroiliac joints in a number of directions, and then conduct a set of five instigative diagnostic tests. If at least three of the latter stimulate your usual pain symptoms, then in order to ascertain whether the SI joint is the root of the problem, the medic will give you a Diagnostic SI joint injection. Of note, this procedure is sometimes referred to as a SI Joint Diagnostic Block. Moreover, it is important to be aware that this procedure is not designed to ameliorate the pain.


The Diagnostic Sacroiliac joint injection comprises a local anaesthetic. This will make your joint numb for a period of 2 to 12 hours, according to the specific medical agent chosen. In order to ensure that the injection is placed precisely into the joint, your doctor will use CT or
fluoroscopic guidance.

The Results

If you find that your SI joint pain has been substantially reduced, then your pain is probably due to your SI joint, and the next stage of your treatment is likely to be non-surgical Sacroiliac Joint treatment, and therapeutic SI joint injections, may be part of this. If this is not the case, then your pain could be due to other causes, all of which your Pain Specialist will explore.

Number 2

In the case of Number 2 (Therapeutic SI Joint Injections), these work to provide short term pain relief. This alleviation varies from patient to patient, and can last anywhere from a number of weeks to a number of months. In some cases, patients have multiple Therapeutic SI Joint Injections over a period of a few years. The injection comprises a combination of the anti-inflammatory corticosteroid, and local anaesthetic, the latter of which offers patients prompt pain relief, while the corticosteroid, provides longer term relief through lowering inflammation.

Your Pain Specialist will monitor how successful the Therapeutic SI Joint Injections are in your individual case, and it is important to make a note in your diary when the pain relief from your last injection diminishes.