Life Fit Blog

3 Tests to Tell You If Your Back Pain is Caused by SI Joint Dysfunction

Posted 1 day ago

Lower back pain is one of the most common complaints among adults, but pinpointing the exact cause can be tricky. For many, the sacroiliac (SI) joint—the connection between the pelvis and the spine—is the culprit. In fact, research suggests that 15-30% of chronic lower back pain cases stem from SI joint dysfunction. If you’ve been struggling with persistent discomfort, it’s worth exploring whether your SI joint is to blame.

What is SI Joint Dysfunction?

The SI joint is a critical shock absorber in your body, transferring forces between your spine and legs. When this joint becomes inflamed or misaligned, it can cause pain in the lower back, buttocks, and even radiate down the legs. Symptoms often mimic other conditions like sciatica or hip arthritis, making diagnosis challenging.

Common triggers include trauma (like a fall or car accident), pregnancy, or repetitive stress. However, lifestyle factors such as poor posture or sedentary habits can also contribute. If you suspect SI joint dysfunction, these three tests can provide valuable clues.

3 Key Tests to Diagnose SI Joint Pain

1. FABER Test

Steps:

  1. Lie on your back
  2. Form figure-four with legs
  3. Press knee downward

Positive: SI joint/groin pain

2. Thigh Thrust Test

Steps:

  1. Lie on your back
  2. Bend affected leg 90°
  3. Press downward on the knee

Positive: SI joint pain

3. Gaenslen Test

Steps:

  1. Lie on your back
  2. Hang affected leg off table
  3. Pull opposite knee to chest

Positive: SI joint/lower back pain

What to Do If You Suspect SI Joint Dysfunction

While these tests can provide insight, they’re not a substitute for professional diagnosis. If you experience pain during any of these tests, consult a healthcare provider. They may recommend imaging tests like X-rays or MRIs, or even a diagnostic SI joint injection to confirm the source of your pain.

How Back Fit Can Help

If you’re dealing with SI joint pain or general lower back discomfort, Back Fit offers a tailored approach to recovery. Our physiotherapist-led course is designed for individuals with acute, chronic, or recurring back pain, as well as those looking to prevent future issues. You can find out more here.

Final Thoughts

SI joint dysfunction can be a hidden source of chronic pain, but with the right diagnosis and treatment, relief is within reach. By understanding the three key tests—FABER, thigh thrust, and Gaenslen—you can take the first step toward identifying the cause of your discomfort.

For those seeking a structured, expert-led approach to recovery, Back Fit offers a proven pathway to improved function and pain relief. Remember, back pain is often a lifestyle issue, and small changes can make a big difference.