SI Joint Dysfunction & SI Fusion: When and Why

SI Joint Dysfunction & SI Fusion: When and Why

Sacroiliac (SI) joint dysfunction is an often-overlooked cause of persistent low back, pelvic, and buttock pain. For some people, the discomfort can radiate into the groin or down the leg, making it easy to mistake SI joint issues for lumbar spine or hip problems. Understanding why SI joint dysfunction happens and when SI joint fusion becomes an appropriate option can help you make informed decisions about your care.

What Is the SI Joint?

The sacroiliac joints connect the sacrum at the base of the spine to the iliac bones of the pelvis. These joints act as shock absorbers, helping transfer weight between the upper body and legs. While the SI joints don’t move much, the small motion they do allow is important for proper mechanics during activities like walking, bending, and standing.

When these joints become irritated, inflamed, or unstable, pain can develop. This condition is known as SI joint dysfunction.

Common Causes of SI Joint Dysfunction

SI joint problems can stem from several sources, including:

• Arthritis or degeneration
  Wear and tear can cause inflammation and stiffness.
  
  

• Instability
  Too much motion in the joint may result from injury, ligament laxity, or childbirth.
  
  

• Trauma
  A fall, accident, or sports injury can disrupt normal joint mechanics.
  
  

• Biomechanical stress
  Leg length discrepancies, abnormal gait, or spinal fusion above the SI joint can increase strain.
  
  

Symptoms That Suggest SI Joint Dysfunction

SI joint pain can mimic other conditions, so diagnosis often requires a detailed exam and imaging. Common symptoms include:

• Pain on one or both sides of the lower back or buttock
  
  

• Pelvic or groin pain
  
  

• Pain that worsens with standing, walking, or climbing stairs
  
  

• Discomfort when rolling over in bed or sitting for long periods
  
  

• Pain that radiates into the thigh
  
  

Treatment Options Before Considering Fusion

Most patients improve with nonsurgical care. Your provider may recommend:

1. Physical Therapy

Strengthening the core, hips, and pelvic stabilizers can reduce strain on the SI joint.

2. SI Joint Injections

Steroid injections help calm inflammation and can also confirm the SI joint as the source of pain.

3. Radiofrequency Ablation (RFA)

This minimally invasive procedure uses heat to reduce pain signals from irritated SI joint nerves.

4. Bracing or activity modifications

A pelvic belt can provide temporary stability for those with joint laxity.

If these treatments provide relief but the pain continues to return, it may indicate underlying joint instability.

When Is SI Joint Fusion Considered?

SI joint fusion is not a first-line treatment. It’s typically recommended when:

• You have chronic SI joint pain lasting six months or more
  
  

• Pain is confirmed to originate from the SI joint through exam and diagnostic injections
  
  

• Conservative treatments have failed
  
  

• Instability or degeneration is affecting quality of life
  
  

• Pain interferes with walking, sleep, or daily function
  
  

Modern SI joint fusion is minimally invasive, requiring only small incisions to place implants that stabilize the joint and encourage bone growth.

Benefits of Minimally Invasive SI Joint Fusion

Patients often consider fusion because it can:

• Improve stability
  
  

• Reduce inflammation and mechanical pain
  
  

• Provide long-term relief
  
  

• Allow faster recovery compared to traditional open surgery
  
  

• Restore normal movement patterns that were limited by pain
  
  

Many patients report meaningful improvement in mobility, sleep, and daily activities following the procedure.

Is SI Joint Fusion Right for You?

SI joint pain can be frustrating, especially when it feels difficult to pinpoint the exact cause. The good news is that SI joint dysfunction is treatable, and for patients who don’t improve with conservative care, minimally invasive SI joint fusion offers a safe and effective long-term solution.

If you’re struggling with persistent low back or pelvic pain, a pain specialist can help determine whether the SI joint is involved and guide you toward the right treatment path.