Sacroiliac SI Joint Dysfunction

Understanding Sacroiliac Joint Pain

Sacroiliac (SI) joint dysfunction is a possible cause of lower back, buttock, and pelvic pain.

The sacroiliac joints connect the sacrum, the triangular bone at the base of your spine, to the pelvis. These joints help transfer weight between your upper body and legs while providing stability during movement.

When an SI joint becomes irritated, inflamed, or does not function normally, it can cause pain that affects walking, sitting, standing, and other everyday activities.

Symptoms of SI Joint Dysfunction

The most common symptom is pain in the lower back or buttock, often on one side.

Other symptoms may include:

• Pain around the hips or pelvis
• Discomfort that extends into the thigh or leg
• Pain when standing up from a seated position
• Discomfort when climbing stairs
• Pain after prolonged sitting or standing
• Increased discomfort with certain movements

Because these symptoms can resemble those of a herniated disc or other spinal condition, a careful evaluation is important.

What Causes SI Joint Dysfunction?

SI joint pain may develop for several reasons, including:

• Injury: Falls, accidents, or other trauma affecting the pelvis.
• Joint changes: Age-related degeneration or arthritis.
• Pregnancy: Changes in joint loading and ligament support during pregnancy and after childbirth.
• Inflammatory conditions: Certain forms of arthritis can cause inflammation of the SI joints, known as sacroiliitis.
• Changes in movement or mechanics: Differences in how the pelvis and spine move or bear weight, including changes following some spinal fusion procedures.

In some cases, the exact cause may not be clear.

Diagnosing SI Joint Dysfunction

Diagnosing SI joint dysfunction begins with a review of your symptoms, medical history, and physical examination.

Your physician may perform specific movements or tests to determine whether the SI joint is contributing to your pain.

Because other conditions can cause similar symptoms, imaging tests such as X-rays, MRI, or CT scans may be recommended to evaluate the surrounding structures or rule out other causes.

In some cases, your specialist may recommend a diagnostic SI joint injection. This procedure involves placing a local anesthetic into the joint to help determine whether it is the source of your pain.