
Sacroiliac joint dysfunction occurs when one or both sacroiliac (SI) joints become inflamed or irritated. These joints connect the sacrum, the triangular bone at the base of the spine, to the iliac bones of the pelvis.
The SI joints support much of the body’s weight and help transfer forces between the upper body and legs. They normally move only slightly and are supported by strong ligaments.
When the joint becomes inflamed or damaged, it can cause lower back and pelvic pain. This condition is sometimes called sacroiliitis.

Symptoms of sacroiliac joint dysfunction may include:
Pain is often felt on one side of the lower back but may occur on both sides.
Diagnosis begins with a medical history and physical examination. A doctor will check for tenderness around the SI joints and perform specific movements that may reproduce pain.
Because SI joint pain can mimic other spine conditions, imaging tests may be used to rule out other causes. These may include:
In some cases, doctors may perform a diagnostic SI joint injection. If pain improves after the joint is injected with a local anesthetic, the SI joint is likely the source of symptoms.
Treatment typically begins with conservative care to reduce inflammation and improve stability.
Common treatment options include:
If pain persists, sacroiliac joint injections with corticosteroids may be used to reduce inflammation and relieve pain.
Surgery, such as SI joint fusion, is rarely needed and is usually considered only after other treatments fail.
Persistent lower back pain, neck pain, or radiating nerve pain should not be ignored. Early evaluation allows for proper diagnosis and targeted treatment, helping prevent progression and long-term complications.