Sacroiliac Joint (SI) Pain

Sacroiliac (SI) joint pain is discomfort that originates from the sacroiliac joints, which are located where the sacrum (the triangular bone at the base of the spine) meets the iliac bones of the pelvis. The SI joints help to transfer weight between the upper body and legs, so dysfunction in these joints can lead to significant discomfort. Approximately 25% of all low back pain is related to the sacroiliac (SI) joints. 

Key Features of Sacroiliac Joint Pain:

• Pain location:
  • Typically felt in the lower back, specifically near the dimples on either side of the lower spine. Please Google Venus dimples!
  • Pain may radiate to the buttocks, hips, groin, and occasionally down one or both legs. Pain from the SI joint can sometimes be confused with sciatica due to its tendency to radiate down the leg. Groin pain is also possible.
• Pain characteristics:
  • Sharp, stabbing, or aching pain: The pain may vary from a dull ache to sharp and stabbing, especially during certain activities.
  • Unilateral or bilateral pain: SI joint pain is often felt on one side of the lower back or pelvis, though it can occur on both sides in some cases.
  • Worsens with movement: Activities like standing up from a seated position, walking upstairs, bending forward, or twisting at the waist can exacerbate the pain.
  • Pain in the morning: Stiffness and pain are often worse in the morning or after long periods of sitting or inactivity.

Common Causes:

• Inflammation (Sacroiliitis): This refers to inflammation of the sacroiliac (SI) joint, often caused by arthritis, trauma, or stress from repetitive motions.
• Trauma or injury: A fall, car accident, or sudden movement can injure the SI joint.
• Pregnancy: Hormonal changes during pregnancy can cause the ligaments in the SI joint to loosen, leading to joint instability and pain.
• Degenerative conditions: Over time, wear and tear can cause dysfunction in the sacroiliac (SI) joint, especially in individuals with lumbar spine or pelvic problems.
• Leg length discrepancy: Differences in leg length can lead to abnormal stress on one SI joint, causing pain.

Diagnosis:

• Physical examination: Your doctor may perform specific tests that stress the SI joint to reproduce pain.
• Imaging: X-rays, CT scans, or MRIs might be used mainly to rule out other conditions. Many people experience significant SI joint pain, yet their CT or MRI scans appear normal.
• SI joint injection: An anesthetic injection into the SI joint can help confirm the diagnosis if it temporarily relieves the pain. We believe this is the best form of diagnosis. Typically, this is a straightforward and quick injection that is performed in the office with the assistance of an ultrasound. Your doctor uses an ultrasound as a camera that is put over your skin. Once the SI joint is seen under the camera, a thin needle will go inside the joint, again all watched with this “camera”.

Treatment:

• Conservative treatments:
  • Rest and activity modification.
  • Physical therapy to strengthen the muscles around the pelvis and lower back. Please look at these exercises here. Do them for a few minutes every day. You will see the change within a few days.
  • Anti-inflammatory medications or muscle relaxants.
  • SI joint belts or braces to stabilize the joint.
• Injections:
  • Corticosteroid injections: In cases of stubborn pain despite the treatments mentioned above, this injection can drop the pain instantly and usually permanently.
  • Platelet Rich Plasma (PRP): A very effective treatment. It is the biggest gun short of surgery.
• Surgical intervention (rarely required): SI joint fusion surgery may be considered if other treatments fail to provide relief.

How is SI joint pain diagnosed?

SI joint pain is a disease with 1000 faces! It can show itself as low back, buttock, or pain similar to sciatica. Most of the time, nothing abnormal is seen in the MRI or X-ray. We usually do a test injection. We inject a few drops of numbing medication under ultrasound guidance into the SI joint. It is so simple and tolerable that we do it in the office by numbing the skin. If the pain decreases significantly with this test injection, then we will proceed with the treatment.