Sacroiliac Joint Injection
Pain that sits deep in one buttock, aches when you sit on that side and catches when you step up a curb is often blamed on the spine or the hip. Many times, the real source is the sacroiliac joint. An SI joint injection does two jobs at once: it delivers anti-inflammatory medicine right into the joint to quiet the pain, and it tells your doctor whether that joint is truly the problem. At MVM Health, our pain specialists use live X-ray guidance to place the medicine exactly where it needs to go, in a visit that usually takes less than 20 minutes.
Book an SI joint evaluation with a pain specialist at one of our clinics in Pennsylvania, New Jersey, Ohio and Arizona.
- Board-Certified Physicians
- Care Across Multiple Specialties
Meet Our Expert Team
Board Certified Expert
At MVM Health — Movement. Vitality. Medicine. — we are committed to providing exceptional pain, vein, and wellness services that empower individuals to reclaim their health and well-being. With our team of Harvard-trained experts, we strive to deliver transformative outcomes that restore comfort, confidence, and quality of life. MVM Health’s mission is to help every patient relieve discomfort, restore motion, and renew life.
Vwaire Orhurhu, MD, MPH
Harvard Medical School
Mariam Salisu, MD, MPH
Harvard Medical School
Peter Isaac, DO
Philadelphia College of Osteopathic Medicine
Ali Amin, MD
Baylor College of Medicine
THOMAS KHOURY, MD
Harvard Medical School
ANTHONY TURNER, MD
Yale School of Medicine
KIRAN C. TAMIRISA
Baylor College of Medicine
TARIQ ALFARRA, DO
JOHNS HOPKINS HOSPITAL
Rishi Sheth, MD
University of Miami School of Medicine
Henry Onyeaka, MD, MPH
Harvard Medical School
Felicia Todd, CNP
Moravian College
Carrie Ward, CNP
Franklin University
Kruti Solanki, CNP
Drexel University
Christy Daniels, CNP
Chamberlain University
Heerina Kittel, CNP
Maryville University
Vic Urbano, CNP
Walden University
Jameela Azeem, CNP
Hofstra University
Vwaire Orhurhu, MD, MPH
Harvard Medical School
Mariam Salisu, MD, MPH
Harvard Medical School
Peter Isaac, DO
Philadelphia College of Osteopathic Medicine
Ali Amin, MD
Baylor College of Medicine
THOMAS KHOURY, MD
Harvard Medical School
ANTHONY TURNER, MD
Yale School of Medicine
KIRAN C. TAMIRISA
Baylor College of Medicine
Rishi Seth, MD
University of Miami School of Medicine
Henry Onyeaka, MD, MPH
Harvard Medical School
Felicia Todd, CNP
Moravian College
Vic Urbano, CNP
Walden University
Jameela Azeem, CNP
Hofstra University
We work with a wide variety of insurance providers
and 100+ more
What Is a Sacroiliac Joint Injection?
The sacroiliac joints are two flat, sturdy joints at the very bottom of your back, where the sacrum, the broad bone at the base of the spine, fits into the pelvis. They take the load of every step, stair and lift. When one becomes irritated or inflamed, it can produce a deep, nagging pain that is hard to pin down.
An SI joint injection places a small amount of medicine directly into the joint, or into the ligaments and nerves right around it. The mix usually contains two parts. A numbing medicine (local anesthetic) works within minutes and wears off over a few hours. A corticosteroid calms the inflammation more slowly, often starting to work after a few days and lasting for weeks to months.
Because back, hip and SI joint pain overlap so much, the injection is also a test. If your usual pain drops sharply while the numbing medicine is active, that strongly suggests the SI joint is the source. This answer guides everything that comes next, from physical therapy to radiofrequency ablation or, in some cases, SI joint fusion.
The SI joint sits deep under bone and thick ligaments, so a “blind” injection often misses. That is why our physicians use live X-ray (fluoroscopy) or ultrasound with a small amount of contrast dye to confirm the needle is in the right spot before any medicine is given.
Types of SI Joint Injections
Your provider chooses the type of injection based on your exam, your imaging and what we need to learn or treat.
Diagnostic SI joint block
Numbing medicine alone, or with very little steroid, is placed into the joint. You track your pain for the next several hours. A clear drop in pain points to the SI joint as the source.
Therapeutic steroid injection
A blend of numbing medicine and corticosteroid is placed into the joint to reduce inflammation and give longer-lasting relief, so you can move more freely and get more out of therapy.
Lateral branch nerve block
Numbing medicine is placed on the small nerves that carry pain signals from the back of the SI joint. If it works, these same nerves can later be treated with radiofrequency ablation for longer relief.
Periarticular (ligament) injection
Medicine is placed in the strong ligaments on the outside of the joint, which can be a pain source on their own. In some cases, regenerative medicine such as platelet-rich plasma (PRP) may be used here.
Common Conditions SI Joint Injections Treat
Sacroiliitis
Inflammation of one or both SI joints, causing a deep ache in the low back and buttock that can worsen with activity.
SI joint dysfunction
The joint moves too much or too little, straining the ligaments and causing one-sided pain, often with a “stuck” or unstable feeling.
SI joint arthritis
Age-related wear of the joint surfaces that leads to stiffness and aching, especially in the morning or after sitting. See our page on arthritis.
Pain after pregnancy
Loosened ligaments and pelvic strain from pregnancy and delivery can leave the SI joint sore for months afterward.
Pain after lumbar spine surgery
After a spinal fusion, the SI joint takes on extra stress and can become a new source of pain below the surgical area.
Inflammatory back conditions
Ankylosing spondylitis and related conditions often affect the SI joints first. Injections can calm flares alongside medical care.
Buttock and leg pain that mimics sciatica
SI joint pain can spread into the thigh and be mistaken for a pinched nerve. An injection helps tell the two apart. See our page on sciatica.
Testing before RFA or fusion
A positive diagnostic block is usually needed before longer-term treatments such as radiofrequency ablation or SI joint fusion.
Risk Factors
SI joint problems tend to show up more often in people who:
- Spend long hours sitting, especially with weight shifted onto one hip
- Have been pregnant, or are in the months after childbirth
- Run, play contact sports or lift heavy loads on a regular basis
- Have had a hard fall onto the buttocks or a car accident
- Walk unevenly because of a hip, knee or foot problem, or one leg that is longer
- Have had surgery on the lower spine
- Live with ankylosing spondylitis, psoriatic arthritis or inflammatory bowel disease
Symptoms
People with an irritated SI joint commonly describe:
- A dull or sharp ache centered over one buttock or just to one side of the tailbone
- Pain you can point to with one finger, just beside the bony bump at the back of the pelvis
- Aching that travels into the groin or the back of the thigh
- Pain when standing on one leg, such as while putting on pants
- Stiffness after long car rides, flights or sitting at a desk
- Discomfort when turning over in bed or crossing your legs
- Pain that eases a little with walking after you get going, then flares with longer activity
When Pain Needs Urgent Care
An SI joint injection is for ongoing pain, not emergencies. Get medical care right away if your low back or buttock pain comes with:
- Loss of control of your bladder or bowels
- Numbness in the groin, genitals or the area you would sit on
- New or quickly worsening weakness in a leg or foot
- Fever, chills or a red, warm, swollen area over the lower back
- Severe pain after a fall, accident or other injury
- Pain at night that does not ease with rest, along with weight loss or a history of cancer
- Chest pain or difficulty breathing (call 911)
These symptoms can mean a serious nerve problem, infection, fracture or other condition that needs prompt attention.
Book a pain evaluation
Other Treatment Options
Spine pain management starts with the least invasive options and steps up only when needed. An epidural is one option among several, and most people with spine pain never need surgery.
Conservative care
Epidural steroid injections
Anti-inflammatory medicine is placed near irritated spinal nerves to ease pain that radiates into an arm or leg, such as from a herniated disc or stenosis.
Facet joint injections and nerve blocks
Medicine is placed in or near the small joints of the spine to ease arthritis pain. A positive response also helps confirm where the pain starts.
Radiofrequency ablation (RFA)
Controlled heat quiets the small nerves that carry pain signals from arthritic spine joints. It’s often considered after a successful nerve block.
Spinal cord stimulation
A small device sends mild electrical pulses that change how pain signals reach the brain. It’s used for long-term pain that hasn’t responded to other care, and it starts with a short trial.
PRP and regenerative medicine
Platelets from your own blood may support healing in some joint and soft-tissue conditions. Your provider will tell you whether it’s a reasonable option for you.
Getting the Most From Your SI Joint Injection
What you do in the hours and weeks after your injection helps you get clear answers and the longest relief.
If pain returns quickly, or you notice fever, new weakness, or redness or drainage at the injection site, call our office.
Callout: Call our office if you have fever, increasing pain, redness or swelling at the injection site, or new numbness or weakness in your legs.
Keep a pain diary for the first six hours. Write down your pain level every hour and try the movements that usually hurt. These notes are key to reading a diagnostic block correctly.
Take it easy for the rest of the day. Light walking is fine, but skip workouts, heavy lifting and yard work until the next day or as your provider advises.
Expect a short-lived numb or heavy leg. The numbing medicine can briefly affect nearby nerves. This usually wears off within a few hours, so have someone drive you home.
Give the steroid time. The anti-inflammatory effect often builds over two to seven days. A brief pain flare in the first day or two can happen before it improves.
Watch your blood sugar if you have diabetes. Steroids can raise blood sugar for a few days. Check it more often and call your primary doctor if it stays high.
Frequently Asked Questions
An epidural places medicine near the spinal nerves to treat nerve pain, such as from a herniated disc. An SI joint injection targets the joint between the spine and pelvis. Learn more about epidural injections.
Many plans do not require a referral, but some do. Your provider will examine you and may review X-rays or an MRI to rule out other causes before the injection.
Yes. If both sides hurt, your physician can usually inject both joints during the same appointment.
That result is useful too. It suggests the SI joint may not be your main pain source, and your provider will look at other causes such as the spine, hip or nerves.
Most physicians limit steroid injections to a few per year in the same area to protect the joint and avoid steroid side effects. Your plan is set based on your response.
Most people return to work and normal routines the day after the injection. If your job is very physical, your provider may suggest an extra day of lighter duty.
Sometimes. Never stop a blood thinner on your own. Our team will check with the doctor who prescribed it and give you clear instructions.
Some people notice a flushed face, trouble sleeping, mood changes or higher blood sugar for a few days. These effects are usually mild and short-lived.
X-ray-guided injections are generally avoided during pregnancy. Tell us if you are or might be pregnant, so we can discuss safer options such as ultrasound guidance or other care.
The SI joint is deep and narrow, and injections done without imaging often miss. Live X-ray with contrast dye confirms the medicine reaches the joint, which improves both relief and test accuracy.
Recent blogs
When Can Leg Discomfort Be a Reason to See a Vein Specialist in Bloomfield, NJ?
Leg discomfort after a busy day is common, especially if you have spent hours standing, walking, or sitting. However, when aching, heaviness, or unusual sensations
How Can Pain Affect Sleep and Daily Activities in Stanhope?
Chronic pain can affect much more than physical comfort. It may interrupt sleep, reduce energy, limit movement, and make ordinary tasks more difficult. When discomfort
Laser, VenaSeal or Sclerotherapy? How to Choose the Right Vein Treatment
You notice it at the end of a long shift or after an afternoon of errands at the King of Prussia Mall. Your legs feel