We get this question a lot: what is a sacroiliac joint injection (also called an SI joint injection) and will it help relieve my lower back, leg, or groin pain?
What Is a Sacroiliac Joint Injection?
There are two kinds of SI joint injections:
- Diagnostic SI joint injections, intended to help determine if your pain is coming from your SI joint
- Therapeutic SI joint injections, intended to temporarily relieve SI joint pain
1. Diagnostic SI Joint Injections
If your doctor suspects that your SI joint is the cause of your low back pain symptoms, he or she will typically perform a series of five provocative diagnostic tests, that involve stressing your SI joints in different directions. If three or more of the five SI joint provocative tests recreate your typical pain symptoms, your doctor may then recommend a diagnostic SI joint injection to confirm that the SI joint is the source of your pain.
A diagnostic SI joint injection, also referred to as a SI joint diagnostic block, is not intended to treat the pain, but instead to help confirm a diagnosis by providing temporary relief.
This SI joint injection video demonstrates how doctors use injections for diagnosis.
What do they inject into sacroiliac joints to help with diagnosis?
A diagnostic SI joint injection contains a short acting numbing agent (local anesthetic) that will numb the joint for 2 to 12 hours depending on the particular agent. The injection is done using fluoroscopic or CT guidance to ensure the injection is delivered directly into the joint.
What can you expect after a diagnostic SI joint injection?
If you have significant reduction in your SI joint pain from the injection, then the SI joint is a likely source of your pain.
If you do not experience significant pain reduction after the diagnostic injection, there may be other causes of your symptoms which should be further evaluated by your doctor.
If you are diagnosed with SI joint dysfunction, the likely next step is non-surgical SI joint treatment, which may include therapeutic SI joint injections.
2. Therapeutic SI Joint Injections
Conservative therapies are non-surgical treatments designed to help relieve SI joint pain so you can go about your daily activities. They can include things like medication, physical therapy, SI joint belts, even SI joint injections, and numbing of the nerves that innervate the SI joint (RFA - radiofrequency ablation). Some patients experience relief with other treatments such as massage therapy, prolotherapy, or chiropractic treatment, however, there is little research that supports these treatments.
Therapeutic SI joint injections are different from diagnostic injections, in that they are intended to provide short term (weeks to months) pain relief.
What do they inject into sacroiliac joints to help with pain?
A therapeutic SI joint injection contains a mixture of local anesthetic and corticosteroid. The anesthetic is intended to provide immediate pain relief while the corticosteroid, which is an anti-inflammatory, is intended to provide longer term relief by reducing inflammation.
How long do therapeutic sacroiliac joint injections last?
The duration of pain relief will vary from person to person. In some cases, it may last for months and in other cases, it may last only weeks or even days. Some people receive multiple therapeutic SI joint injections over the course of several years and the duration of relief may diminish with each injection. Initially, relief may last many months and after multiple injections, the duration of relief becomes shorter until finally, the injections provide limited or no relief.
Are there side effects associated with therapeutic SI joint injections?
Corticosteroids have potential side effects, so your doctor will likely prescribe a maximum of two or three therapeutic SI joint injections over a 12-month period. In addition, some insurance companies will only pay for 2 or 3 therapeutic SI joint injections over the course of a year.
Some potential side effects of SI joint injections of steroids are:
- Bruising at the site of the injection
- An allergic reaction
- Increased localized pain or bleeding
- Negative effects on metabolism (weight gain, increased blood pressure, and high blood sugar levels)
- Suppression of the adrenal glands which produce other necessary steroids for your body
- Degeneration of the joint surface (cartilage)
- Reduced elasticity and flexibility of the surrounding ligaments and soft tissues
Download this pamphlet to record the results after your diagnostic injection(s) and for a brief description of SI joint pain treatment.If non-surgical SI joint treatment such as SI joint injections don't work for you, the next step may be to consider minimally invasive SI joint fusion, such as iFuse.
SI Joint Dysfunction Pain and Treatment
Pain from sacroiliac joint dysfunction can be felt anywhere in the low back, buttocks, or in the legs. Chronic SI joint pain symptoms can make it difficult to perform common daily tasks, and can affect many aspects of a patient's life.The good news is, there are thousands of doctors around the world who are trained in SI joint pain treatment, from conservative therapies to minimally invasive SI joint fusion surgery.
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More Related Resources
More links and information regarding the diagnosis and treatment of SI Joint Pain:
- SI Joint Diagnostic Tests
- SI Joint Injection Video
- SI Joint Injections for Diagnosis
- Sacroiliac (SI) Joint Diagnosis and Injections Pamphlet (PDF)