The most common cause of SI joint pain is Sacroiliitis.

Sacroiliitis is an inflammation of one, or both, of the sacro-iliac joints located where the lower spine connects with the pelvis. Though it rarely requires surgery, Sacroiliitis can cause pain in the buttocks or lower back that can extend down into the legs. Often, patients suffering from this condition will experience pain after extended periods of standing, walking or climbing.

Since sacroiliitis is a condition caused by inflammation, there are a number of issues that can cause it. These include:

  • Wear and tear arthritis, also known as osteoarthritis, can occur within the sacro-iliac joints as can ankylosing spondylitis, an inflammatory form of arthritis that affects the spine.

  • Traumatic injury such as a fall or car crash that affects the buttocks, lower back or hips.

  • Pregnancy can cause inflammation as a result of the widening and stretching of the sacro-iliac joints to prepare for childbirth. On top of this, the weight gained during pregnancy can put excessive amount of stress on the joints and lead to abnormal wear.

  • In rare occasions, infection can occur in the sacro-iliac joints or an infection in a separate part of the body can cause inflammation in the joints.

Patients can experience the symptoms of sacroiliitis in a number of different ways, however it commonly is related to the amount of pressure or stress that is put on the sacro-iliac joint. Common causes include:

  • Standing for long periods of time

  • Climbing stairs

  • Transitioning from sitting to standing

  • Running



The symptoms of sacroiliitis commonly include pain in the lower back or buttocks region. Occasionally, pain caused from inflammation within the sacro-iliac joint can be a little deceiving and manifest itself in seemingly unrelated areas like the legs, groin and the feet, though this is unusual.


Sacroiliitis can be difficult to diagnose simply because the symptoms it creates can be caused from other conditions. Doctors will typically begin their diagnosis by performing a physical exam, often by trying to locate the source of pain by putting pressure on places in the legs, spine, hips and buttocks. They may also ask the patient to perform various stretches in order to put slight stress on the SI joints.

X-rays, MRI’s and other similar imaging tests can also show signs of damage and inflammation within the sacro-iliac joint. Typically a spine specialist will order an imaging test if they suspect ankylosing spondylitis or other forms of arthritis to be the primary cause of pain.


Treatment of sacroiliitis can vary based on the severity of the condition and the amount of pain a patient is experiencing.

Typically, however, sacroiliitis can be remedied through a combination of rest, heat / ice therapy and anti-inflammatory medication like ibuprofen. Combined, these simple treatments can help reduce inflammation while allowing the body to deliver healing nutrients to the affected portions of the SI joint.

In more severe cases, your spine doctor might recommend sacro-iliac joint injections to help combat pain. If this treatment is chosen, the physician will often inject a numbing agent, likely lidocaine, and a steroid which contains powerful anti-inflammatory medication directly into the SI joint using fluoroscopic guidance.

Injections can be administered three to four times a year and should be accompanied with physical therapy to help properly rehabilitate the joint.

Surgery is very often the last line of defense when it comes to sacroiliitis and is rarely required. However, for patients who are suffering from severe pain that is unresponsive to nonsurgical options and is inhibiting their everyday lives, SI Joint Fusion is a viable option. This surgery effectively stabilizes the joint and increases load-bearing capacity by fusing the joint together through a brief and minimally invasive procedure.

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Atlantic Brain and Spine A graduate of both Yale and Stanford, Dr. Jae Lim is a board-certified spine surgeon who specializes in minimally invasive spine surgery and robotic spine surgery, significantly reducing surgical impact and recovery times. (703) 876-4270
8501 Arlington Blvd. Suite 330
United States
Jae Y. Lim Ben L. Nguyen