Columbia Pain & Spine Institute

Sacroiliac Joint Injection

A sacroiliac joint injection delivers anti-inflammatory steroid and local anesthetic directly into the SI joint under fluoroscopic (X-ray) guidance to relieve low-back and buttock pain caused by sacroiliac joint dysfunction.

OVERVIEW

What a sacroiliac joint injection is and how it works

The sacroiliac (SI) joints sit where the base of the spine (the sacrum) meets the pelvis (the ilium), one on each side just below the small of the back. When an SI joint becomes inflamed or moves abnormally, it can produce pain in the lower back, buttock, hip, and sometimes the back of the thigh. A sacroiliac joint injection places medication precisely inside the joint to calm that inflammation.

At Columbia Pain & Spine Institute in Gresham, the injection is performed under fluoroscopy (live X-ray) so the physician can confirm the needle is inside the joint space before any medication is delivered. The injection combines a long-acting corticosteroid, which reduces inflammation over time, with a local anesthetic that can ease pain quickly. The procedure serves two purposes: it is diagnostic, because immediate pain relief from the anesthetic helps confirm the SI joint is the source of your pain, and it is therapeutic, because the steroid can provide longer-lasting relief over the following days and weeks.

Diagnostic and therapeutic. If your pain noticeably improves right after the injection, that response points to the SI joint as the pain generator and helps guide further care, such as a confirmatory sacroiliac joint nerve block or other targeted treatments.

CONDITIONS

What a sacroiliac joint injection commonly treats

This injection is most often used when pain is traced to the SI joint rather than a disc or facet joint.

Commonly treats

Sacroiliac joint dysfunction SI joint inflammation (sacroiliitis) Low-back pain over the SI joint Buttock and posterior hip pain SI-related pain after pregnancy Post-traumatic SI joint pain SI pain after lumbar fusion Sacroiliitis from inflammatory arthritis

WHAT TO EXPECT

Your visit, step by step

Before

Your physician reviews your history, exam, and imaging to confirm the SI joint is the likely source. Tell us about blood thinners, allergies, or possible pregnancy. You may be asked to track your pain levels for the hours after the injection, since that response is part of the diagnosis.

During

You lie face down while the skin is cleaned and numbed. Using fluoroscopic guidance, the physician advances a thin needle into the SI joint, often confirming placement with a small amount of contrast dye, then injects the steroid and anesthetic. The injection itself usually takes only a few minutes, and most patients are in and out in well under an hour.

After

You rest briefly and then go home the same day. Arrange a ride if sedation is used. You may feel sore at the injection site for a day or two; the anesthetic can ease pain right away, while the steroid typically takes a few days to reach full effect. Many patients resume normal activity quickly.

Why image guidance matters. The SI joint has an irregular, deep shape, so guiding the needle with fluoroscopy helps confirm the medication is placed inside the joint rather than the surrounding tissue.

FAQ

Common questions about sacroiliac joint injections

Is the sacroiliac joint injection a test or a treatment?

It can be both. The local anesthetic gives quick, short-term relief that helps confirm whether the SI joint is causing your pain, while the corticosteroid works to reduce inflammation for longer-lasting relief. How much you improve, and for how long, varies from person to person.

How soon will I feel relief, and how long does it last?

Many patients notice some relief within the first hours from the anesthetic, which may then fade before the steroid takes effect over the next several days. Duration of relief differs for each patient and depends on the underlying cause, so your physician will review your response at follow-up to plan next steps.

What happens if the injection helps only briefly?

A clear but temporary response still gives valuable diagnostic information that the SI joint is the source of your pain. If pain returns, your physician may recommend repeating the injection or, after a confirmatory sacroiliac joint nerve block, moving to a longer-lasting option such as radiofrequency ablation of the SI joint nerves or, for an unstable joint, sacroiliac joint fusion.

RELATED & NEXT STEPS

Explore related SI joint care

Sacroiliac joint injections are one part of our interventional approach to SI joint pain for patients across Gresham, Portland, and the greater Portland metro. Learn more about related procedures and how to reach our team.

SI joint procedures

See the full range of sacroiliac joint treatments on our SI joint procedures hub.

Related procedures

Compare options such as a SI joint nerve block, radiofrequency ablation, and SI joint fusion.

All services

Browse our complete list of interventional pain services in Gresham and Portland, Oregon.

To find out whether a sacroiliac joint injection is right for you, talk with our team. Referrals are accepted by fax at (503) 382-8120, and patients are welcome to call our office.