SI Joint Pain: Symptoms, Causes, and What Helps

The ache sits right where your back pocket meets your belt line. It flares when you climb out of the car or roll over in bed. You've wondered whether it's your back, your hip, or something else. It might be your SI joint, and it's more common than most people think.

What is SI joint pain?

SI joint pain is pain from one or both sacroiliac (SI) joints, where your lower spine meets your pelvis. You have two, one on each side, just below the dimples of your lower back. They're built for small, sturdy movements and help pass your body weight between your spine and legs.

When these joints are swollen and irritated, doctors call it sacroiliitis¹. When they move too much, too little, or unevenly, you may hear SI joint dysfunction. Both cause similar pain.

It's not rare. A 2022 review in American Family Physician found SI joint problems in about 25% of adults with chronic low back pain². Women are more likely to have it than men, and it's common during and after pregnancy².

The SI joint is one of several sources of hip-area pain. Our hip pain guide shows how to sort them out by where it hurts.

What does SI joint pain feel like?

Most people feel it low in the back, at or just below one of the dimples above the buttock. According to Mayo Clinic¹, pain is most often felt in the buttocks and lower back. It can also spread down the thigh, and sometimes into the groin or foot¹.

The review notes the pain can be on one or both sides, but usually isn't in the middle of the spine². Some people can point to the sore spot with one finger. That simple sign is part of how clinicians size it up².

These everyday moves tend to set it off:

What causes SI joint pain?

SI joint pain can start suddenly after an injury, or build slowly from repeated strain. According to the 2022 review², common triggers include:

• A sudden jolt: a car crash, a fall onto your buttocks, or heavy lifting^1,2
• Repeated twisting and loading: sports like golf, gymnastics, and football²
• Arthritis: wear-and-tear arthritis, or ankylosing spondylitis, a type of arthritis that affects the spine^1,2
• Pregnancy and the months after birth: loosened joints, extra weight, and a changed walk add strain^1,2
• Uneven movement: one side of the pelvis moving too much or too little²

Infection of the SI joint is possible but rare¹. Mayo Clinic also lists lack of exercise, which can leave the muscles around the joint tight¹.

Long commutes and desk days don't cause SI joint pain on their own. They can make an irritated joint ache, though, since long sitting is a classic trigger^1,2.

Is it SI joint pain, sciatica, or lower back pain?

They overlap, which is why an exam matters more than a guess. SI joint pain usually sits low and off to one side, near the dimple above the buttock. General lower back pain is often across the low back or in the muscles beside the spine.

Sciatica is pain from an irritated nerve. It tends to run down the back of the leg, often below the knee, and may bring numbness or tingling. SI joint pain can spread into the thigh, too, so the two are easy to mix up. Learn more about telling sciatica or hip pain apart, and hip pain or back pain.

No single test confirms SI joint pain. Clinicians use a group of gentle movement tests that press or stretch the joint. When three or more reproduce your pain, the SI joint is a likely source². Your doctor also checks your lower back, hips, and nerves to rule other causes in or out.

Outer hip pain at the bony point of the hip is a different problem. See hip bursitis for that pattern.

Why does SI joint pain happen during pregnancy?

During pregnancy, your body loosens these joints to prepare for birth. Added weight and a changing walk add more strain¹. The NHS calls the wider problem pelvic girdle pain, and says up to 1 in 5 pregnant women may have it to some degree³.

You may feel it across one or both sides of the lower back, over the pubic bone, or into the thighs³. Walking, stairs, standing on one leg, and turning in bed often make it worse³.

The NHS suggests a few everyday changes³:

• Stay active within your limits, and rest when you need to.
• Sit down to get dressed, and keep your weight even when standing.
• Sleep with a pillow between your knees.
• Keep your knees together when getting in and out of the car.
• Limit long sitting, long standing, frequent stairs, and heavy lifting.

The NHS also notes that pelvic girdle pain isn't harmful to your baby³. Tell your OB or midwife about it. We work alongside your OB, and our doctors offer gentle care for pregnancy. Read more about pelvic pain during pregnancy.

When does SI joint pain need medical care first?

Most SI joint pain isn't an emergency. A few signs point to something that needs a medical provider before chiropractic care.

New bladder or bowel problems can mean pressure on the nerves at the base of the spine (cauda equina syndrome). That needs emergency care.

See a provider soon if pain spreads below the knee, or comes with weakness, numbness, or tingling in your legs⁵. The same goes for unexplained weight loss⁵.

One more pattern deserves a medical check. Back and buttock pain that's worst in the morning or at night may be inflammatory. So is pain that eases with exercise but not with rest⁴. When it starts between 18 and 40, ask your medical doctor about ankylosing spondylitis⁴.

What helps SI joint pain?

Exercise and hands-on care are the usual first steps. The 2022 review recommends physical therapy, spinal adjustment (manipulation), or both as first-line care². That recommendation rests on moderate evidence, so it's a reasonable start rather than a sure thing.

Exercise

Programs that stretch the front of the hip and the deep buttock muscles help. So does strengthening the muscles around the pelvis². These programs showed benefit over the medium and long term².

Hands-on care

According to the review, spinal adjustment gave short-term relief. Combined with exercise, results lasted longer than exercise alone². That's why exercise stays part of the plan.

Support belts

A pelvic support belt may help steady the joint during and after pregnancy^2,3.

Day-to-day changes

Break up long sitting with short walks. Switch sides when you carry bags or a toddler. Try sleeping on your back or your pain-free side.

When pain lingers

If pain doesn't ease with these steps, your medical doctor may discuss injections or other procedures².

Can a chiropractor help?

Yes, for many people it's a reasonable place to start. Your doctor listens to how the pain started and what sets it off. Then your doctor checks your lower back, pelvis, and hips, and watches how you walk. X-rays are taken only when your exam calls for them.

Care may include gentle joint movement, gentle muscle work, and exercises for the pelvis and hips. Adjustments are an option only if you want them. Your doctor explains what they found, and you choose your care.

Find out what's behind your SI joint pain

You've tried a new chair, a new mattress, and a heating pad on the low back. The ache still finds you on the stairs and every time you roll over. It's hard to make plans around pain when you're not sure where it starts.

We're here to help you find out. Chiropractic Company has cared for Greater Milwaukee since 1982, with 400,000+ patients, 1,400+ five-star Google reviews, and 20+ neighborhood clinics. Our doctors care for hip and pelvic pain every week. We look for the cause of your pain, not just the symptoms. Your care is designed around your condition, your medical history, your daily routine, and your goals. You choose your care, and you see the same doctor as it continues.

Care is natural and drug-free. Treatment begins at your second visit, or the same day in acute cases if your doctor decides it's appropriate. Some plans add physical therapy at our Menomonee Falls, Waukesha, and West Allis North clinics, or massage therapy at Hales Corners and Oconomowoc.

We're in-network with most insurance companies and accept Medicare and auto accident claims. Eligible new patients can start with the $29 new-patient special, which includes a consultation, an exam, and X-rays if needed. *See offer terms.

Visit one of our 20+ neighborhood clinics across Greater Milwaukee: Milwaukee East, Milwaukee North, Milwaukee Third Ward, Shorewood, Glendale, Mequon, Cedarburg, Grafton, Germantown, Brookfield, Menomonee Falls, Waukesha, Oconomowoc, New Berlin, West Allis, West Allis North, Greenfield, Hales Corners, Franklin, Muskego, and Cudahy.

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