What Is Sacroiliac Fusion?

• In simple terms: SI fusion joins the sacrum (base of the spine) and ilium (pelvic bone) together using implants so the painful joint no longer moves.
  
  

• Scientifically: SI fusion involves percutaneous placement of implants (typically titanium or 3D-printed porous devices) across the SI joint under fluoroscopic guidance, promoting bony arthrodesis and eliminating pathological micromotion.
  
  

Conditions Treated

• Sacroiliac joint dysfunction causing chronic low back and buttock pain
  
  

• Sacroiliac degeneration from arthritis or wear and tear
  
  

• SI joint instability after trauma, pregnancy, or spine surgery (e.g., after fusion extending to the sacrum)
  
  

• Failed conservative treatment (PT, injections, bracing)
  
  

Pre-Operative Workup

• History & exam: SI joint provocative maneuvers (e.g., FABER test)
  
  

• Imaging: X-ray, CT, MRI to confirm SI degeneration and rule out lumbar spine issues
  
  

• Diagnostic injection: Pain relief after SI joint injection confirms diagnosis before fusion
  
  

• Optimization: PT, medications, and bracing are tried first; surgery only if pain persists
  
  

The SI Fusion Procedure: Step by Step

Plain-English overview

1. Anesthesia & positioning: You’re asleep (general anesthesia), lying face down.
   
   

2. Small incision: A 2–3 cm incision is made along the buttock.
   
   

3. Guided implant placement: Using live X-ray (fluoroscopy), instruments are passed across the SI joint.
   
   

4. Joint stabilization: 2–3 implants are placed to secure the joint.
   
   

5. Closure: Incision closed with sutures or glue; many patients go home the same day.
   
   

Surgeon-level detail

• Approach: MIS lateral buttock incision; dissection to lateral ilium under fluoroscopic control.
  
  

• Trajectory: Guide pins advanced across ilium into sacrum; confirm with AP/inlet/outlet views.
  
  

• Preparation: Drilling/burring across SI joint, decortication of bone to promote fusion.
  
  

• Implant insertion: 2–3 triangular titanium or porous-coated implants placed across joint; position confirmed with multiple fluoro angles.
  
  

• Fixation: Immediate stability achieved; long-term fusion occurs as bone grows through implants.
  
  

• Closure: Layered closure; sterile dressing.
  
  

Benefits of SI Fusion

• Minimally invasive; outpatient in most cases
  
  

• Small incision with low blood loss
  
  

• Faster recovery compared to open SI joint fusion
  
  

• Provides permanent stabilization for painful SI dysfunction
  
  

• High success rates in properly selected patients
  
  

Risks & Limitations

• Infection, bleeding, implant malposition
  
  

• Nerve irritation (rare, minimized by careful fluoroscopic guidance)
  
  

• Non-union (failure to fuse)
  
  

• Persistent pain if other pain generators present (lumbar spine, hip, etc.)
  
  

• Not appropriate if pain isn’t truly from the SI joint (diagnostic injections are key)
  
  

Recovery Timeline

• Day of surgery: Walking the same day; discharged home
  
  

• Week 1–2: Mild soreness; light activity encouraged
  
  

• Weeks 2–6: Gradual return to daily activities; restrictions on heavy lifting/twisting
  
  

• 6–12 weeks: Fusion maturing; physical therapy may begin
  
  

• 3–6 months: Most patients resume full activity with long-term pain relief
  
  

Why Choose Desert Spine and Pain?

• Expert neurosurgeon: Dr. Greenwald is skilled in minimally invasive SI fusion techniques
  
  

• Comprehensive care: Diagnostic injections, PT, and conservative care are always attempted first
  
  

• Patient-first approach: Surgery only when it’s truly necessary and beneficial
  
  

• Advanced technology: Image-guided implant placement for maximum safety and accuracy
  
  

Frequently Asked Questions

How do I know if my pain is from the SI joint?

A diagnostic injection that relieves your pain confirms the joint as the source.

Will SI fusion cure my back pain?

If your pain truly comes from the SI joint, fusion can provide long-term relief. If pain is from another source, results may vary.

How long until I feel better?

Many patients notice improvement within weeks, with maximum benefit by 3–6 months.

Will I lose mobility after SI fusion?

No. The SI joint has very limited motion normally, so fusion does not affect flexibility.

How does Desert Spine and Pain perform SI fusion differently?

We combine neurosurgical precision, advanced implants, and careful patient selection to maximize safety and outcomes.