Short answer: pain low on one side of the back, near the dimple above the buttock, is often put down to the sacroiliac (SI) joint. Sometimes the joint is part of it. But the same spot can hurt because of the lower back, the hip or the tendons around the buttock, and “your pelvis is out of place” is rarely a useful explanation. What usually helps is working out what aggravates it, adjusting those things, and building the strength around the pelvis step by step.
What it is
The sacroiliac joints are the two joints where the base of your spine (the sacrum) meets the pelvis. They are strong, held together by thick ligaments, and move only a small amount. That small movement is normal and is part of how load passes between your spine and your legs.
SI joint pain often looks like this:
- An ache low on one side of the back, sometimes with a sore spot you can point to with one finger
- Pain spreading into the buttock, and sometimes the groin or back of the thigh
- Worse with stairs, getting out of a car, rolling over in bed or standing on one leg
- Worse with long sitting or standing in one position, then easing when you move
Why “out of place” isn’t the whole story
You may have been told the joint is “out of alignment” or “stuck”. That is a common explanation, but there is little to show that a joint this strong and this tightly bound slips out of place, and a pelvis that looks uneven is common in people with no pain. I don’t use that explanation.
What I see more often is a joint and the tissues around it that have become sensitive because they were asked to do more than they were ready for: a sudden jump in running or lifting, a new job on your feet, a change in sleep or sitting habits. Pain is a protective signal, not a measure of damage, and a sensitive area can be calmed down and rebuilt.
Or is it something else?
No scan proves SI joint pain, and the diagnosis is made by assessment. Pain in this area also commonly comes from:
- The lower back. Referred pain from the spine often lands in the same spot. See back pain and sciatica.
- The deep buttock. See piriformis syndrome and what else it can be.
- The outside of the hip. See hip bursitis or tendon pain.
- The hip joint. Often felt in the groin. See knee and hip osteoarthritis.
These need different plans, which is why guessing from a video tends to go nowhere.
What usually helps
Start with what aggravates it. For many people it is long sitting or standing, stairs, single-leg loading such as running or lunging, or a particular sleeping or driving position. There is no list of banned positions. It is usually pretty basic: change the things that flare it for a while, then build back.
Then build capacity. I lean towards gentle holds (isometric work) to settle it, then strength through the glutes, hips and trunk in steps. With SI joint pain I am conservative. I would rather you stay at the low end of discomfort while you do it, and back off sooner if it lingers, spreads or is worse the next day. The right dose depends on you, which is why it is set after an assessment.
I use hands-on work, mostly massage and joint mobilisation, where it helps, alongside the loading. I don’t use pelvic belts or taping myself, though they help some people, and they are worth asking about if you are curious.
I don’t use dry needling, ultrasound or shockwave, and I explain why in my dry needling post. That is my choice for my practice, not a claim about every clinician. If you are considering an injection, discuss it with your doctor.
Pregnancy and after birth
SI joint and pelvic girdle pain is common during pregnancy and after birth. I see pregnant women for problems unrelated to the pregnancy. For pelvic girdle pain linked to pregnancy or birth, I would suggest seeing a physio with women’s health training.
How long does it take?
It depends on what is driving it, how long you have had it and what you need your body to do, so it can’t be known before an assessment. As a rough guide, I usually see people for at least six visits, and sometimes ten to twelve for longer-standing or more stubborn cases. I plan for a finish line: once it is under control and you know how to manage it, I discharge you rather than book maintenance.
When to get it checked
See your GP if you are under about 45, the pain came on gradually, you are stiff for more than half an hour in the morning, and it eases with movement and not with rest, or it wakes you in the second half of the night. That pattern can point to an inflammatory condition of the spine and pelvis, which needs a doctor’s assessment.
Get urgent medical help for new problems controlling your bladder or bowel, numbness around the genitals or anus, or weakness or numbness in both legs. See a doctor promptly for pain with a fever or feeling unwell, after a significant fall or accident, or if you have had cancer. Constant pain at night that doesn’t change with position, a leg that is getting weaker, or pain that hasn’t improved after a few weeks should also be assessed.
What the first appointment involves
I see people at Shop 8 / 19 Ways Road, Hampstead Gardens. The initial appointment is $150 (45 minutes), HICAPS is on site, and no referral is needed for private appointments. I take a history first: where it hurts, what sets it off, what changed. Then I test how your lower back, pelvis and hips move and handle load, and what reproduces the pain. You leave knowing what I think is going on, what I am not sure of yet, and what the first few weeks look like. You usually don’t need a scan first. If I think you need imaging or a doctor, I’ll say so.
Fees and claiming are on the services and FAQ pages.
Common questions
Is my pelvis out of alignment? Probably not in the way the phrase suggests. Uneven-looking pelvises are common in people with no pain, and I don’t treat the picture. I assess how the area moves and copes with load.
Should I stretch it or have it “put back”? Usually not as the main plan. Gentle strengthening that you can build on tends to work better than chasing a click or a quick fix.
Do I need an X-ray or MRI? Usually not at the start. Changes on scans are common in people with no pain, and SI joint pain is diagnosed by assessment, not by the picture.
Can I keep exercising? Often yes, at a level that doesn’t leave it worse the next day. Cutting back, not stopping, is usually the first step.
I treat back, pelvic, hip and groin pain at my clinic in Hampstead Gardens, Adelaide. For the wider picture, see hip and groin physio.