Sacroiliac (SI) Joint Pain: Causes, Symptoms & How Chiropractic Helps

What Is Sacroiliac (SI) Joint Pain?

Sacroiliac joint pain — often shortened to SI joint pain — is discomfort coming from the joints where the base of your spine meets your pelvis. You have two of these joints, one on each side, and they sit low and toward the outside of your lower back, roughly where the dimples above your buttocks are. Pain from them is typically felt low and to one side of the back, in the buttock, or spreading into the hip.

The SI joints are easy to overlook because they don't move much and rarely get talked about — yet they're doing important work. They form the bridge that transfers the weight of your upper body down into your legs, and they absorb and distribute load every time you stand, walk, or climb stairs. When one of these joints becomes irritated, stiff, or moves in an unbalanced way, it can produce a surprising amount of pain. Because that pain sits low in the back and sometimes travels into the buttock and leg, it's very commonly mistaken for sciatica — a distinction this article gives its own section, since telling them apart changes the plan.

What's Happening in Your SI Joint

To understand SI joint pain, picture where it lives. At the base of your spine is a triangular bone called the sacrum, and on either side of it are the broad wings of the pelvis, the ilia. The sacroiliac joints are where sacrum and pelvis meet, held together by some of the strongest ligaments in the body. Unlike the mobile joints of your neck or lower back, these are built for stability — they move only a little, and their job is to stay solid while transferring load.

Trouble arises when that finely balanced stability is disturbed:

• Too little or uneven motion. If one SI joint stiffens or the two sides move unevenly, the joint and its ligaments get irritated — the most common pattern, and one chiropractic care is well suited to address.
• Too much motion. When the supporting ligaments loosen — classically in pregnancy — the joint can become unstable and painful.
• Muscle involvement. The muscles around the pelvis, including the buttock muscles, tighten protectively and can refer pain of their own; this overlaps with piriformis syndrome, another common buttock-pain source that can also mimic sciatica.

Because the SI joint sits at a crossroads between the spine, the pelvis, and the hip, and because irritated tissue here can send pain into the buttock and leg, figuring out that the joint itself is the source takes a careful, hands-on assessment rather than a guess from where it hurts.

What Causes SI Joint Pain?

SI joint pain usually comes from something that disturbs the joint's normal balance and load-sharing. Common contributors include:

• Pregnancy, when hormones loosen the pelvic ligaments and a shifting center of gravity loads the joints — one of the most common causes, covered further in our pregnancy care guide
• A fall or awkward landing onto one side, or a misstep off a curb, that jolts the joint
• Lifting or twisting under load, especially with poor mechanics
• Repetitive one-sided loading, from sport or a job that favors one leg
• Leg-length differences or foot mechanics that make the pelvis carry weight unevenly, sometimes helped by custom orthotics
• Prolonged sitting or standing in a posture that loads one side of the pelvis

Sometimes there's a clear trigger, like a fall; other times the joint is gradually irritated by months of uneven loading, so the onset feels vague. Either way, the pattern of what aggravates it is one of the most useful clues at your exam.

Common Symptoms

SI joint pain has a fairly recognizable signature:

• Pain low and to one side of the back, often pointed to right around the dimple above the buttock
• Pain that spreads into the buttock or hip, and sometimes into the back of the thigh
• Flares with specific movements — climbing stairs, getting in and out of a car, rolling over in bed, or standing on one leg
• Discomfort with prolonged sitting or standing, easing when you shift position
• A sense of the pelvis feeling stiff, "stuck," or uneven

Unlike a typical disc-driven sciatica, SI joint pain usually stays around the buttock and upper thigh rather than shooting all the way down past the knee, and it doesn't usually come with the numbness, tingling, or true weakness of a compressed nerve. That difference is exactly what the next section unpacks.

SI Joint Pain vs. Sciatica

This is the distinction that matters most, because the two are so easily confused — both can cause pain in the buttock and leg — yet they come from different places and call for a different focus.

• SI joint pain comes from the joint itself. It tends to center low and to one side of the back, near the buttock, and to flare with one-sided loading like stairs, rolling over, or standing on one leg. The pain usually stays around the buttock and upper thigh, without the numbness or tingling of a nerve problem.
• Sciatica is a symptom of an irritated nerve, most often from a lumbar herniated disc or other disc problems. It typically travels further down the leg — often past the knee, sometimes to the foot — and frequently brings tingling, numbness, or weakness along that path.

Who's Most at Risk?

SI joint pain can affect anyone, but it's more common in:

• Pregnant women, by a wide margin — the ligament loosening and weight shift of pregnancy load the SI joints directly
• Athletes in sports with running, cutting, or single-leg loading, from the strain of sports injuries
• People who've had a fall or awkward landing onto one side
• Older adults, as the joint and its ligaments accumulate wear
• People with a leg-length difference or foot mechanics that load the pelvis unevenly
• Anyone whose work or habits involve repetitive one-sided loading

Often more than one applies. A new parent recovering from pregnancy while lifting a growing child, for example, is loading the SI joints in exactly the ways that tend to keep them irritated.

How SI Joint Pain Is Evaluated

Because SI joint pain sits at the crossroads of the spine, pelvis, and hip — and because it mimics sciatica — a careful evaluation is what makes targeted care possible. At Thrive Chiropractic, Dr. Rubinstein starts with a detailed history: exactly where it hurts, whether it travels down the leg and how far, which movements set it off, and whether pregnancy, a fall, or one-sided activity is part of the picture.

The physical exam typically includes:

• SI-specific provocation tests — gentle maneuvers that load the joint to see whether they reproduce your pain, which helps confirm the SI joint as the source
• Motion and alignment checks of the pelvis and lower back, comparing the two sides
• A neurological screen — reflexes, strength, and sensation — to check for the nerve involvement that would point toward true sciatica instead
• Muscle and hip assessment, since the buttock and hip muscles can both refer pain and be part of the problem

Imaging isn't automatic. Most SI joint pain is diagnosed and managed on the history and exam. Imaging is reserved for specific reasons — a significant injury, red-flag symptoms, or pain that isn't improving as expected. If one of those applies, Dr. Rubinstein will arrange the right imaging or referral rather than continue hands-on care alone.

What to Expect at Thrive Chiropractic

At Thrive Chiropractic in Troy, MI, care for SI joint pain is conservative and built around your exam findings — the goal is to restore balanced motion to the joint and pelvis and calm the tissues around it. Care often includes:

• Chiropractic adjustments or mobilization to restore balanced, comfortable motion to the SI joint and pelvis, easing the irritation driving your pain
• Soft-tissue and massage therapy to release the tight buttock and hip muscles that build up around an irritated joint
• The Webster technique for pregnant patients — a gentle, pregnancy-specific approach focused on pelvic balance and comfort
• Custom orthotics when uneven foot mechanics or a leg-length difference are loading the pelvis asymmetrically
• Movement, posture, and stability coaching to support the joint and reduce the chance of the pain returning

The plan is honest about what's realistic: chiropractic care manages and relieves SI joint pain and helps restore balanced motion — it's not a one-time cure, and most recoveries happen over a series of visits. You'll get a specific sense of your timeline after the exam. For pregnancy-related SI pain, care is gentle and adapted to each trimester, and often continues comfortably right through pregnancy.

Caring for Your SI Joint at Home

A few habits can genuinely help alongside professional care.

A few more that tend to help:

• Break up prolonged sitting or standing, shifting position and moving before the joint stiffens.
• Ease off one-sided loading — carrying a child on one hip, or a heavy bag on one shoulder — while the joint settles.
• Build gentle core and hip stability, which gives the pelvis better support day to day.

If your pain is getting worse despite these steps, or it starts shooting further down the leg with numbness or tingling, treat that as a signal to be evaluated rather than waited out.

When to See a Chiropractor

Occasional one-sided stiffness after heavy activity or a long day is normal. It's worth getting evaluated when SI joint pain keeps coming back, doesn't ease within a couple of weeks, flares with everyday movements like stairs or getting out of a car, or interferes with sleep, work, or activity. This is especially true in pregnancy, where gentle care can make a real difference in comfort. Getting ahead of it gives conservative care the best chance to work.

A small set of symptoms, though, are true emergencies — they suggest pressure on the nerves at the base of the spine and should never be waited out.

Short of those emergencies, pain that shoots down the leg with numbness or tingling is a good reason to be seen sooner rather than later — both to relieve it and to sort out whether the SI joint, a nerve, or both are involved. When you're ready, you can schedule a visit with Dr. Rubinstein for a thorough exam.

Frequently Asked Questions

SI joint pain raises a lot of understandable questions — how to tell it apart from sciatica, whether a chiropractor can help, why it's so common in pregnancy, how it differs from general lower back pain, and which movements make it worse. Those are answered in detail in the FAQ section on this page.

If you've got low, one-sided back or hip pain and want a clear picture of what's going on, schedule a visit with Dr. Rubinstein at Thrive Chiropractic in Troy, MI. You'll get a thorough exam, an honest read on whether the SI joint or a nerve is involved, and a conservative plan aimed at relieving the pain and restoring balanced motion. You can also explore the wider Back Pain library for related topics like lower back pain and piriformis syndrome.