What is sacroiliac joint fusion?
The sacroiliac joints connect the sacrum at the base of the spine to the pelvis. Fusion places implants across the affected joint to reduce movement and support bone growth across it. The aim is to improve symptoms when the SI joint has been carefully established as an important pain source; improvement is not guaranteed.
Why diagnosis comes first
SI joint pain can resemble pain from the lower spine or hip, and imaging alone cannot establish the pain source. Assessment usually combines the symptom pattern, several physical examination tests, imaging to look for other conditions and the response to an image-guided diagnostic injection.
When is it considered?
Fusion is generally considered only after suitable non-surgical treatment has not provided adequate control. This may include activity modification, medication, physiotherapy and image-guided injection. Lateral-branch radiofrequency treatment can be relevant to some posterior SI pain, but it is not a mandatory step before fusion in every case.
Risks, alternatives and recovery
Risks include infection, bleeding, nerve injury, implant malposition or failure, failure of the bones to join, persistent pain and further surgery. Alternatives may include continued rehabilitation, medication, injection or denervation, depending on the pain source. Walking and loading are progressed according to the surgical approach, bone quality, symptoms and early healing.
How we approach your care
- 01
Find the true source
We begin with a thorough history and examination, supported by imaging where appropriate, to pinpoint the precise source of the problem.
- 02
Consider appropriate options
Where clinically appropriate, we consider established non-surgical options before surgery. The plan depends on the diagnosis, symptoms, health and priorities of the individual patient.
- 03
A plan built around you
Every step is explained clearly, so you always understand your options and what comes next.
This may help if
- History and examination consistently point to the sacroiliac joint as an important pain source
- Image-guided diagnostic injection has produced meaningful temporary relief and other likely causes have been assessed
- Appropriate non-surgical treatment has not provided adequate control
Suitability can only be assessed after reviewing your symptoms, examination, relevant imaging and previous treatment.
Common questions
How is SI joint pain diagnosed before fusion?
No single scan proves that the SI joint is causing pain. The decision normally combines the history, several physical examination tests, imaging to assess other conditions and the response to an image-guided diagnostic injection.
Must I have denervation before fusion?
Not necessarily. Physiotherapy, medication and injections are commonly considered first. Lateral-branch radiofrequency treatment may be reasonable for some posterior SI pain, but it is not a universal requirement before fusion.
What are the risks?
Risks include infection, bleeding, nerve injury, implant malposition or failure, the bones not fully joining, persistent pain and the need for further surgery. Your surgeon should explain the risks that are most relevant to the proposed approach and your health.