Stabilising the Sacroiliac Joint

Surgery might be an option to treat your sacroiliac (SI) joint dysfunction and limit the amount of movement of the sacroiliac joint. Your doctor may recommend a minimally invasive surgical procedure that fuses the SI joint.

SI Fusion System

SI Joint Fusion System Rialto

SI joint fusion surgery is intended to stabilise your sacroiliac joint and provide an environment for fusion (joining bones together into one solid structure) to occur.

The specifically designed SI joint fusion system that uses a posterior approach consists of cylindrical threaded devices designed to enhance sacroiliac joint fusion.

The threaded devices are offered in various lengths to accommodate the anatomy. For fusion of the SI joint, one, two, or three devices may be placed at the surgeon’s discretion. 


Most SI fusion devices require the surgeon to perform the procedure from the side of the body, using a lateral approach. A system is now available in Australia and New Zealand that is specifically designed to use a posterior approach, meaning the surgeon enters from the back, avoiding muscle disruption.


Muscles are disrupted with a lateral approach.


Minimal muscle disruption with a posterior approach.

Advantages of the posterior approach include:

  • Easier access — the device passes through less tissue and muscle during the implantation
  • Less invasive — fewer muscles are disrupted during the procedure

If you have questions about the SI fusion system, please consult with your doctor, the only one qualified to diagnose and treat your condition.


Risks of SI Joint Surgery

Potential risks in any surgical procedure include unforeseeable complications caused by anaesthesia, blood clots, undiagnosed medical problems, such as silent heart disease, and rare allergic reactions. 

In addition, some risks of SI joint surgery include incomplete pain relief, damage to the nerve roots, infection, and complications with the hardware.

Most of these complications can be treated once they are detected, but sometimes they require a longer period of hospitalisation or recovery, additional medications, and sometimes even additional surgery.

These risks will be explained by the primary surgeon. In general, these complications happen very infrequently, but it is important to remember that surgery is a difficult process, and, therefore, unforeseeable complications do occur. 


Data is from a Medtronic survey conducted with physicians who are using posterior SI fusion approach and have previous experience in transgluteal/lateral SI fusion. Over 80% of the responding physicians stated that these attributes of a posterior approach were better compared to the transgluteal/lateral approach. The survey was not intended to compare specific products used.

This website is intended to be educational and is not to be used as a diagnostic tool. It is not intended to replace the information provided to you by your healthcare providers and does not constitute medical advice. The information may not be directly applicable for your individual clinical circumstance. Please talk with your doctor about diagnosis and treatment information.