Sacroiliac Fusion



Sacroiliac Fusion is a surgical procedure intended to join the sacrum the pelvis. Surgeons follow two steps to prepare the sacroiliac joint for fusion. First, the bony surfaces of the joint are roughed up. Second, a screw is placed across the sacroiliac joint so it cannot move. Movement prevents bone growth and fusion. Once the surgeon is completed the actual “fusion” process, joining two parts together with bone, is done by you. Our bodies have a built in mechanism for healing fractures. Roughing up the bony surfaces signals your body to knit the bones together by laying down new bone. The hardware prevents movement from breaking up the new bone, and allowing the fusion process. When the joint no longer moves, it no longer hurts.


If your sacroiliac joint pain lasts more than 12 weeks despite treatment with moist heat, naproxen or ibuprofen, and chiropractic care, then fusion could be the right solution for your pain.

Sacroiliac pain is common in people who have:

  1. Arthritis
  2. Deformity (Scoliosis)
  3. Fractures of the Tailbone
  4. Ankylosing Spondylitis

A surgeon confirms your pain is coming from your sacroiliac joint using a three step process. First, they listen to your symptoms, and see if you are typical of sacroiliac pain. Second, they examine you for tenderness of the joints, as well as your x-ray, CT and MRI for signs of sacroiliac disease. If you pass the first two steps, then they block the pain fibers going into your sacroiliac joint under x-ray guidance. If that doesn’t relieve your pain for a few hours, then they attempt to block your pain by injecting numbing medicine into the joint itself.

They perform the block of the pain fibers going into your sacroiliac joint from the back. If that block relieves all your pain, then the best treatment is denervation of the pain fibers going into your sacroiliac joint. This is a direct visualized rhizotomy, where an endoscope is used to find the pain fibers to the joint and divide them forever. On the other hand, if the block fails to relieve all your pain, then they repeat the block with an injection directly into your sacroiliac joint. If the block inside your joint totally relieves your pain, then sacroiliac fusion is the right procedure for your pain.

Spine surgeons have done thousands of spinal fusions over more than 15 years, and are experts in minimally invasive spinal fusion. They use minimally invasive surgical techniques for sacroiliac fusion as well.


Sacroiliac fusion surgery usually requires 60 – 90 minutes of surgical time. Add about 30 min for anesthesia before and after. Most patients are out of the recovery area about an hour after waking up from the operation. The surgery is outpatient, so you go home the same day. You will be sore with muscle pain in the buttock muscle, but the pain will not be severe.

Once home we ask patients to walk with crutches or a cane for 6 weeks. Remember, it takes 6-12 weeks for a broken bone to heal. The key is to avoid bearing weight on the side of your fusion. We call this “toe touch weight bearing.” You will be given a set of crutches and a quick lesson how to do this before your operation. As the surgery pain goes away and the fusion matures, you will feel the sacroiliac pain melt away.


Check out a video about SI Fusion from SI Bone

Zyga’s page about SI Fusion