How Your PT Determines If Your SI Joint Is Causing Your Pain

Your physical therapist can use various methods to determine if your back pain is coming from your lumbar spine or from your sacroiliac (SI) joint. These methods can help form an accurate mechanical diagnosis of your condition and can ensure you perform the correct treatment for your back or SI joint pain.

If you have low back pain, you may benefit from working with a physical therapist to determine the cause of your problem and to relieve your pain. Your PT can also help you recover your normal, everyday function. One of the challenges of managing low back pain and sciatica—pain in your leg that comes from your back—is determining the source of your pain.

Sources of back pain may include:

  • Lumbar discs
  • Facet joints
  • Low back muscles
  • Vertebral bodies
  • Sacroiliac joint

With so many different structures that cause back pain, it becomes a challenge to determine the exact cause.

The SI joint may be a cause of your back pain, and it may even cause you to feel pain in your thigh or lower leg. Your SI joint may also cause hip and groin pain. So how do you know if your SI joint is the culprit or if your lumbar spine is causing your pain? Your PT can help.

Photo of PT moblizing a patient's spine.
BurgerPhanie / Getty Images

Basics of the SI Joint

The sacroiliac joint is a large joint in the back of your pelvis. It is formed by the articulation of your sacrum bone and the ilium bone. The joint is a very stable one, with only slight motions occurring there. Sometimes trauma or, more rarely, repetitive stress and strain, can cause the SI joint to move out of place. This can cause pain and limited motion around your low back or hip.

For years, there has been a debate on whether the SI joint moves at all and if it can be a pain generator in the back and hip. More recent research implicates the SI joint as one cause of back and hip pain, with some estimates of the joint causing pain in 6 to 26 percent of all back pain cases. The trouble here is that when you move your lumbar spine, the SI joint is stressed, and when you move the SI joint, the lumbar spine is stressed. With these motions occurring almost simultaneously, it becomes difficult to determine if the true cause of your back pain is from your SI joint or lumbar spine.

Another challenge to properly diagnosing SI joint pain: there is no gold standard diagnostic test. Special tests like an X-ray or MRI simply do not show the SI joint in great detail. The current best way to diagnose an SI joint problem is by injecting steroids into the joint and monitoring the change in symptoms. Unfortunately, injections into the SI joint may be risky and may cause problems like increased pain or infection.

How Your PT Determines If Your SI Joint Is Causing Your Pain

When visiting your physical therapist for treatment for back pain, he or she may suspect your SI joint as a cause of your symptoms. If the SI joint is suspected, there are a few clues to help your PT make an accurate mechanical diagnosis.

General characteristics of an SI joint problem may include:

  1. Typically symptoms come on as a result of trauma like a fall or automobile accident.
  2. The SI joint rarely "goes out" suddenly as a result of minor forces or activities, such as rising from a chair.
  3. Pain is felt only on one side of the back.
  4. Pain is not felt above the lumbar 5 level (near the waistline).
  5. There is no midline back pain and pain does not cross over to the other side.
  6. Pain does not centralize with repeated lumbar motions like the lumbar press up or the lumbar side glide.

When these symptoms are present, your PT may suspect an SI joint dysfunction as the cause of your pain. This suspicion is confirmed by performing SI joint provocation tests. These special tests are designed to stress your SI joint, and they Indicate if your SI joint is causing your back pain.

There are seven SI joint provocation tests, and when at least three of them cause pain (or reduce your pain), the SI joint can be considered as a cause of your back pain, hip pain, or sciatica. Your physical therapist is trained to perform these SI joint provocation tests.

Many times with back pain, your history and description of symptom behavior is enough to rule in our out a disc or joint problem. The SI joint goes against this rule; patient descriptors of symptom behavior offer little diagnostic information, making the diagnosis of SI joint dysfunction a difficult one.

First Steps to Treatment

If your PT determines that your SI joint may be causing your back pain there are some things you should do get started on treatment. These may include:

  • Using an SI joint belt to help control excessive motion around your joint
  • Exercises to help stabilize your SI joint
  • Applying kinesiology tape to the joint
  • Using heat or ice for symptomatic relief
  • Using PT modalities to help control inflammation and pain

The goals of PT for an SI joint dysfunction are to restore the normal position of the joint and to stabilize the joint to prevent future problems with it. Keeping your SI joint in place should be enough to decrease or eliminate your back or hip pain so you can return to your normal activities.

If your SI joint pain persists and limits your normal activities once you have attempted PT, you may need to consider more invasive treatments like steroid injections or surgery. These treatments should be discussed with your doctor.

One of the challenges of managing back problems is determining the cause of your pain. Your sacroiliac joint may be one area that can cause back, hip, or sciatic pain. Your PT can use various techniques to determine if the SI joint is causing your pain, and he or she can provide the right treatment for you. That way you can decrease your pain and return to your previous level of function and activity.

Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  • Laslett, Mark. Evidence-Based Diagnosis and Treatment of the Painful Sacroiliac Joint. Journal of Manual and Manipulative Therapy. 16(3). Jul, 2008; 142-152.
  • Medcalf, R. (16, November 19). MDT Management of Sacroiliac Joint Disorders. Lecture presented at McKenzie Method Clinical Skills Update in Cleveland, OH.