Sacroiliac Joint Injury

The sacroiliac joint (abbreviated 'SI joint') is a firm, thin joint that is at the junction of the spine and the pelvis. Most often when we think of joints, we think of knees, hips, and shoulders—joints that are made to undergo motion. The sacroiliac joint does not move much, but it is critical to transferring the load of your upper body to your lower body.

What Causes SI Joint Pain?

SI joint pain is most often joint inflammation as a result of repetitive activity or overuse. People often refer to SI joint inflammation as sacroiliitis. Other causes of SI joint pain include arthritis of the SI joint, infection of the joint, or ligament sprains of the ligaments that surround the joint. There are also several systemic conditions including ankylosing spondylitis, gout, and calcium pyrophosphate dihydrate deposition disease.

Symptoms of SI Joint Pain

Sacroiliac joint pain can be a difficult problem to diagnose for a few reasons:

• The SI joint is not easily palpated or manipulated
• Examination tests do not to isolate just the SI joint
• Studies (X-Rays, MRIs, CAT Scans, Bone Scans) are often normal
• Several other problems (back pain, sciatica, hip arthritis, etc.) can cause similar symptoms

Diagnosing SI joint abnormalities begins with understanding the symptoms, a careful examination, and possibly some imaging tests. Trying to feel the SI joint can be difficult, but pain and tenderness in the lower back/upper buttock are characteristic of SI joint pain. Certain tests can place pressure across the joint and may indicate a problem in that region. One test, called the FABER test, is done by lying down, flexing the hip, abducting the leg, and rotating the hip. This maneuver places pressure directly across the sacroiliac joint.​

If the diagnosis is still unclear, an injection into the SI joint can help determine the source of pain. In this procedure, an injected anesthetic is placed into the SI joint. If the injection alleviates the symptoms, then the test is positive for the sacroiliac joint as a source of the problem. This test may be performed in conjunction with a cortisone injection for treatment of SI joint problems.

SI Joint Treatments

Sacroiliac joint inflammation tends to respond well to simple treatments.

• Rest: The first step in treatment is to avoid the activities that cause symptoms. For athletes, this may mean avoiding their sport to let the inflammation subside.
• Anti-Inflammatory Medications: Anti-inflammatory medication can help to minimize the inflammation. It is important to understand that the anti-inflammatory medication is not given as a pain medicine, but rather to decrease the inflammation. Therefore, stopping the medication before your healthcare provider tells you to stop can prevent complete treatment. Even if the pain goes away, the anti-inflammatory properties of these medications may still be effective.
• Physical Therapy: Physical therapy is often a helpful treatment. A physical therapist can help strengthen the muscles around the SI joint and low back and help increase flexibility around the joint. They may also try modalities including ultrasound and electrical stimulation to control pain and inflammation.

If SI joint pain persists despite these treatments, an injection of cortisone into the joint may be effective. The cortisone injection delivers a more powerful anti-inflammatory medication directly into the sacroiliac joint itself. Because the SI joint is deeper within the body than most joints, the cortisone injections are usually given under X-ray guidance in a hospital.

Surgery is seldom needed for SI joint pain but can be performed. The most common surgery is an SI joint fusion to permanently stabilize the joint so that there is no longer motion at the SI joint.