Disclaimer: This article is for general educational purposes only and does not constitute medical advice. Always consult a qualified health professional for advice specific to your condition. © 2026 Better Physiotherapy Bundoora.
Sacroiliac joint pain is estimated to account for up to 25% of all low back and buttock pain — yet it remains one of the most commonly misdiagnosed conditions. Many patients are told their pain is "disc related" or "from the spine" before a thorough assessment identifies the SI joint as the true source.
What Is the Sacroiliac Joint?
The sacroiliac joints are the two large joints connecting the sacrum (the triangular bone at the base of your spine) to the ilium (the large wing-shaped pelvic bone) on each side. They are strong, heavily reinforced joints that normally move very little — they transfer load between the spine and lower limbs rather than producing movement. When they become irritated, stiff, or hypermobile, they generate significant pain.
Causes of Sacroiliac Joint Pain
Common triggers and contributors include:
- Pregnancy — relaxin-driven ligament laxity allows excessive SI joint movement
- Trauma — falls onto the buttock, motor vehicle accidents
- Asymmetrical loading — leg length discrepancy, habitual single-leg postures
- Spinal fusion surgery — adjacent segment stress following lumbar fusion
- Inflammatory arthritis — ankylosing spondylitis, psoriatic arthritis affecting the SI joints
- Deconditioning — weakness of the gluteal and core muscles that normally stabilise the joint
How Physiotherapy Treats Sacroiliac Joint Pain
Treatment is tailored to whether the SI joint is hypermobile (moving too much) or hypomobile (stiff and restricted):
- Hypomobile SI joint: Manual therapy — joint mobilisation and manipulation — to restore normal movement, combined with stretching of tight hip flexors and piriformis
- Hypermobile SI joint: Stabilisation exercises targeting transversus abdominis, multifidus, and gluteal muscles; pelvic belts for short-term support
- Both presentations: Education on aggravating postures, activity modification, and a home exercise program to maintain gains
What to Expect at Your Appointment
Your physiotherapist will take a detailed history, then perform a cluster of provocative SI joint tests to confirm the diagnosis. Lumbar spine and hip assessments are also performed to rule out referred pain from those areas. In most cases, treatment begins in the first session. Most patients notice meaningful improvement within 2–4 appointments.
SI Joint Pain Treatment at Better Physiotherapy Bundoora
Sacroiliac joint pain is one of our most commonly treated presentations. Our physiotherapists are experienced in both the assessment and management of SI joint dysfunction, including in pregnancy. Call (03) 9467 6900 or book online today.
Frequently Asked Questions
What does sacroiliac joint pain feel like?
SI joint pain typically presents as a dull ache or sharp pain in the lower back, just above the buttock crease, almost always on one side. It may radiate into the buttock, groin, or posterior thigh (but rarely below the knee). It is characteristically aggravated by prolonged sitting, standing on one leg, walking upstairs, and rolling in bed.
How is SI joint pain diagnosed?
A physiotherapist diagnoses SI joint pain using a cluster of provocative tests — distraction, compression, FABER, thigh thrust, and Gaenslen's tests. A positive cluster (3 or more tests) has good diagnostic accuracy. Imaging (X-ray, MRI) is rarely necessary and often normal in SI joint dysfunction.
How long does SI joint pain take to resolve?
Acute SI joint pain triggered by a specific event (lifting, pregnancy, trauma) typically resolves in 4–8 weeks with physiotherapy. More chronic presentations can take 8–12 weeks. Pelvic stabilisation exercises are the most important component of long-term recovery.
Is sacroiliac joint pain common in pregnancy?
Very common. Pelvic girdle pain (PGP) affecting the SI joints occurs in up to 25% of pregnancies, due to ligament laxity driven by the hormone relaxin. Physiotherapy, including pelvic belts, manual therapy, and targeted exercise, is safe and effective during pregnancy.
Ashley Haleel
Physiotherapist & Owner — Better Physiotherapy Bundoora