Sacroiliac Joint Dysfunction: Understanding Pain Around the Back of the Pelvis

The sacroiliac joints sit where the sacrum meets the two sides of the pelvis. Pain in this region is commonly felt near one side of the lower back or upper buttock and may become more noticeable during walking, stairs, rolling in bed, standing on one leg, or transitioning from sitting to standing.

The term sacroiliac joint dysfunction is often used broadly, sometimes to describe almost any pain around the back of the pelvis. This can create confusion because low-back structures, hip muscles, lumbar discs, and other tissues can produce pain in a similar location.

The sacroiliac joint itself can be a genuine source of pain, but identifying it requires more than simply feeling one side of the pelvis and deciding it is rotated or out of alignment.

A useful assessment looks at symptom location, provoking activities, clinical testing, hip and lumbar movement, previous injury, and whether the presentation fits a sacroiliac pain pattern better than other possible sources.

The SI Joint Moves Less Than Many People Assume

The sacroiliac joint is a strong, load-transferring joint supported by substantial ligaments and surrounding muscles. It does move, but the amount is relatively small compared with the hip or lumbar spine.

This is important because SI joint pain is frequently explained as the pelvis repeatedly slipping out of place. That explanation can make the person feel structurally unstable and dependent on repeated realignment.

In most cases, a more useful model involves joint sensitivity, changes in load tolerance, surrounding muscular guarding, and how force is being transferred through the pelvis.

The joint can be painful without being dislocated or mechanically misplaced.

This creates a more realistic rehabilitation goal: improve how the pelvis tolerates load rather than constantly correcting its position.

Walking and Single-Leg Tasks Can Bring Symptoms On

During walking, the body repeatedly transfers weight from one leg to the other. The pelvis, hips, and trunk help manage this force while the sacroiliac joints contribute to load transfer between the spine and lower limbs.

Someone with SI-region pain may therefore notice discomfort while walking, climbing stairs, standing on one leg to get dressed, or getting out of a car. These activities all involve asymmetrical loading.

The person may begin shortening the stride or spending less time on the painful side. Over time, this can create weakness or additional guarding around the hips.

Rehabilitation often needs to restore confidence and capacity in single-leg loading rather than simply treating the joint while the person lies on a table.

Pregnancy and Postpartum Changes Can Influence the Region

Pelvic girdle and sacroiliac-region pain are common during pregnancy and can continue postpartum for some people. Hormonal changes, increased abdominal load, altered gait, and the physical demands of pregnancy all influence how the pelvis and surrounding muscles work.

After delivery, the body then needs to recover while simultaneously managing feeding positions, carrying, interrupted sleep, and repetitive lifting.

This can create substantial demand through the low back and pelvis even when the pregnancy itself has ended.

Treatment should remain supportive and avoid framing the pelvis as permanently unstable. Strength and movement can be rebuilt gradually, and pelvic health physiotherapy may be appropriate when other pelvic-floor or postpartum symptoms are present.

Hip Strength Can Influence Load Transfer

The gluteal muscles and other hip muscles help control the pelvis during walking, stairs, and single-leg movement. Reduced strength does not automatically cause SI joint pain, but it can influence how force is managed around the pelvis.

Someone who has been protecting one side may also lose strength because the painful leg is being used less.

Strengthening therefore often becomes part of rehabilitation. Exercises may progress from controlled bilateral movements into single-leg tasks, step work, split squats, carrying, and other functional patterns depending on the person’s needs.

The purpose is not to lock the SI joint in place. It is to improve the capacity of the surrounding system to handle load.

Low Back and Hip Problems Can Mimic SI Joint Pain

Pain near the posterior pelvis can originate from the lumbar spine or hip as well as the SI joint. A lumbar disc problem may refer pain into the buttock, while hip conditions can create discomfort that is difficult to localize.

This overlap is one reason diagnosing SI joint pain based on touch alone can be unreliable.

Assessment should include lumbar movement, hip range, neurological symptoms where relevant, and specific provocation testing rather than assuming the joint is responsible because the pain is near it.

A more accurate diagnosis helps avoid repeated treatments aimed at the wrong structure.

Where Manual Therapy Fits

Manual therapy can be useful when SI-region pain is associated with muscular guarding, hip restriction, or painful movement through the lumbar-pelvic region. Hands-on care may improve comfort and make walking or transitional movements easier.

The treatment should not be presented as repeatedly putting the pelvis back into alignment. The SI joints are highly stable structures, and normal asymmetry does not automatically indicate dysfunction.

Manual therapy can reduce protective tension and improve surrounding movement, after which strengthening and functional exposure become important.

The goal is to make the pelvis less sensitive to load rather than dependent on correction.

Belts and External Support Can Be Useful in Selected Cases

Some people with pelvic girdle or SI-region pain find temporary relief from an external support belt, particularly during pregnancy or periods when walking and standing are very uncomfortable.

The belt can provide additional compression and sensory feedback around the pelvis.

This does not mean the pelvis is structurally unstable. The support may simply make load transfer feel more comfortable while symptoms are irritable.

If a belt is useful, it can be treated as a temporary tool rather than something the person must rely on indefinitely.

The longer-term plan still involves restoring movement and capacity.

Sitting and Transitional Movements Can Be Provocative

SI-region pain can become noticeable during prolonged sitting or when moving from sitting to standing. Rolling in bed or getting in and out of a vehicle may also provoke symptoms because the pelvis is loaded asymmetrically during the transition.

Small modifications can help while symptoms are sensitive. Changing position more often, adjusting how the person gets out of the car, or temporarily avoiding very prolonged static postures may reduce repeated irritation.

These are not permanent movement rules. They are ways of reducing unnecessary aggravation while the region becomes more tolerant.

As symptoms settle, the person should gradually return toward normal movement.

When SI-Region Pain Needs Further Assessment

Pain around the pelvis can occasionally reflect conditions outside the sacroiliac joint. Significant trauma, fever, systemic illness, unexplained weight loss, neurological changes, or pain that behaves atypically require further evaluation.

Persistent symptoms that fail to improve with appropriate rehabilitation may also need reconsideration of the diagnosis.

The goal should not be to keep treating the SI joint indefinitely simply because the pain is in the same area.

If the expected pattern does not fit, the source should be reassessed.

The Goal Is Confident Load Transfer Through the Pelvis

The sacroiliac region is designed to transfer force between the trunk and legs. Recovery therefore depends on making that load feel manageable again.

An OsteoMed assessment can look at hip and lumbar movement, single-leg loading, muscular strength, gait, and the activities that reproduce symptoms. Where appropriate, manual therapy can reduce surrounding guarding while strengthening and progressive exposure rebuild confidence.

The aim is not a perfectly aligned pelvis. It is a pelvis that can tolerate walking, stairs, lifting, exercise, and normal daily movement without repeatedly becoming the limiting factor.