Sacroiliac joint pain and lower back pain: why assessment matters

What is the sacroiliac joint?

The sacroiliac joint, often shortened to SIJ, connects the sacrum at the base of the spine with the pelvis on each side. Strong ligaments support the area as forces pass between the trunk and legs. Pain can arise from structures within or around the joint, which is one reason the broader term “sacroiliac joint complex” is used.

Discomfort is often felt on one side around the back of the pelvis or buttock. Some people notice it when climbing stairs, getting out of a car, turning in bed or standing on one leg. These patterns are useful clues, but none is a diagnosis by itself. Pain can also extend towards the thigh or groin.

Why assessment matters more than a pain label

An assessment starts with the story: how the pain began, which activities provoke it, previous injuries and how symptoms change through the day. The examination may look at walking, hip and spinal movement, strength and a group of tests that place controlled stress around the pelvis. A single tender point or positive test cannot reliably confirm that the SIJ is responsible.

The international SIJ consensus guideline describes important limitations in diagnosis and treatment evidence. Test findings need to be interpreted together, including whether other causes fit better. A clinician should explain both their working diagnosis and any remaining uncertainty.

Pain spreading into the leg is not automatically sciatica. Tingling, numbness or weakness makes a nerve assessment particularly relevant. Our guide to sciatica assessment and treatment explains how nerve-related pain differs from other referred pain.

Does a click mean the joint has been put back?

A click or a feeling of release during treatment does not establish that a joint was displaced and has now been corrected. A small study using precise imaging measurements found no change in sacroiliac joint position after manipulation, despite changes in clinical test findings. Its size and age limit what it can tell us, but it does not support a simple “bone put back into place” explanation. Read the original study.

This does not mean hands-on treatment can never relieve symptoms. The useful question is whether it helps you move and take part in rehabilitation. For low back pain, NICE recommends considering manual therapy only within a programme that includes exercise. Repeatedly chasing a crack is not a complete management plan.

What can a rehabilitation plan involve?

Begin with a specific everyday goal: walking to the shops, sleeping more comfortably or managing a flight of stairs. Discuss which activities remain manageable and which need temporary adjustment. A shorter walk or breaking a task into smaller parts may be a more useful starting point than avoiding movement altogether.

Exercise can then be selected around what the examination shows. It may involve gradually rebuilding hip and trunk strength, balance or tolerance of stepping and lifting. There is no single “SIJ correction” exercise that everyone needs. Research specifically about conservative SIJ treatment is limited, so claims of one guaranteed routine deserve caution.

Keep track of whether the plan improves function over time. If an exercise produces increasing pain, new leg symptoms or a lasting reduction in your normal activity, it needs review. The next step may be a smaller movement, a different exercise or reassessment of the diagnosis. Once everyday activities are settling, our guide to returning to the gym explains a gradual approach.

When might a scan or referral be needed?

Routine imaging is not recommended for uncomplicated low back pain. A scan should answer a clinical question and be likely to change management. It may be relevant when the history suggests a fracture, inflammation or another condition needing a different approach. An imaging finding does not automatically explain the pain.

Tell your clinician about marked morning stiffness, pain waking you at night, psoriasis, inflammatory bowel disease or a history of eye inflammation. Taken together with the rest of the assessment, these may prompt GP or rheumatology review. New weakness, significant trauma and other warning signs also change the pathway.

If symptoms remain disabling despite appropriate care, specialist assessment may help clarify the next step. Specialist procedures are a separate decision with their own indications and risks; they are not a routine first step for pain around the pelvis.

When to get urgent help

For sudden severe or rapidly worsening pain, or back pain with fever, shivering or feeling generally unwell, contact an urgent GP service or NHS 111. Arrange a GP review for unexplained weight loss, persistent night pain or symptoms that are not improving. These recommendations follow NHS back-pain guidance.

Back-pain assessment in Hull

If symptoms are limiting work, sleep or exercise, an assessment can help you decide what to change and whether further investigation is needed. At Resolve MSK Clinic, 44 Bond Street, Hull, the appointment considers your history, movement and strength, with sensation, reflexes and other nerve tests where appropriate.

Clinical care is led by Kenneth Mgbakogu, an HCPC-registered physiotherapist and independent prescriber with NHS primary care and musculoskeletal experience. Read what to expect from back-pain assessment and physiotherapy in Hull, including rehabilitation and referral options.