The sacroiliac (SI) joint is like the forgotten child in the back pain family. It usually goes overlooked in back pain topics but it plays a fundamental role in our body’s stability and movement.
While the sacroiliac joint can be a possible root cause for low back pain, it is stated that it causes about 25% of these cases.  Additionally, another source reports that 13% of individuals with chronic low back pain (LBP) have SI joint dysfunction and 15-30% of LBP is caused by SI joint injury.  With these statistics, hopefully, this article serves you well in helping you manage your pain and helping you to count those sheep.
SI Joint 101: Sleeping Position for Sacroiliac Joint Pain Relief
Before we jump into the whole how should I sleep section, it makes sense to review the anatomy of the sacroiliac joint. It will make connecting the dots from pain relief to sleeping position easier to understand.
You’ll find the SI joint at the base of your spine between the sacrum and ilium bones of the pelvis (hence, the name). There are 2 joints, one on each side of the sacrum.  The most important role of this joint is serving as a shock absorber and transferring forces between the upper and lower body.
The sacroiliac joint holds a lot of responsibility when it comes to daily movement, so any discomfort will be inevitably noticeable. Doing things such as walking, standing, and lifting require the stability and reinforcement of the SI joint.
The Top 3: Sleeping Positions for Sacroiliac Joint Pain Relief
With low back pain being the most common symptom of SI joint pain, let’s take a look at the positions that can help alleviate this.
- Sleeping on your back: This position is a common solution for LBP. If you sleep on your back with a pillow under your knees you can facilitate spinal alignment and reduce any pressure on your SI joint. The video in this section also shows a variation with knees high to allow your pelvis to lie flat on the bed and provide relief.
- Side-lying: Lying on your side, also with a pillow between your knees can help maintain spinal alignment and reduce any unnecessary strain. There is a specific variation to this if your discomfort is persistent. Sleeping at a 45-degree angle may help. Please check out the short video at the end of this section for clarification!
- Prone (On your stomach): A pillow will need to be placed on your lower abdomen, allowing the top of your pelvis to be pushed up slightly. (Also described in the video below.)
At the Pregame: Sleeping Position for Sacroiliac Joint Pain Relief
Experiencing pain in your sacroiliac joint can arise from (but not limited to) the following list of causes.
Traumatic SI Joint Pain Causes:
- Pelvic ring fractures
- Soft tissue injury (for example: falling onto buttocks)
- Indirect injury from motor collision
- Repeated lifting
- Strain or twisting 
Atraumatic SI Joint Pain Causes:
- Previous lumbar fusion
- Leg length abnormality
- Scoliosis 
Like most muscle or joint issues, high-intensity, repetitive, or torsional movement may trigger SI pain. Sports such as golf, bowling, or skating are some examples. Also, the combination of weight gain affecting lower spinal curvature during pregnancy can cause SI joint pain.
Both younger and older people can experience sacroiliac joint pain with the former being commonly caused by sports injuries and the latter by degeneration.
- Pain that extends down the thigh and up to the knee
- Pain while sitting down or climbing stairs
- Pain while lying on the affected side
According to the article Sacroiliac Joint Pain and Dysfunction, SI joint pain can have a referral pattern that can extend to the lumbar region, buttock, greater trochanteric area, groin, thigh, abdomen and finally, calf. 
Diagnostic Tests or Assessments:
- Physical Assessment by a Healthcare Professional
- Stress Tests: Usually involve specific movements or pressure applied to the joint to reproduce pain (examples include Gaenslen’s test or Patrick’s test/FABER test)
- Imaging Studies: X-rays, CT scans, MRIs 
Sacroiliac joint pain, just like other musculoskeletal conditions, can often be treated conservatively. Following professional help, pain management is highly individualized and outcomes will differ. Diagnosing SI joint pain can be difficult and requires a skilled provider to successfully rule out other causes.
Conservative treatment would include things such as physical therapy, lifestyle changes (exercise and proper body mechanics), and medication such as NSAIDs or sometimes injections. The more invasive measures would include surgery - although outcomes here will vary!
Sleeping Position for Sacroiliac Joint Pain Relief: Your Bedtime Routine Matters
Since we’ve established the best sleeping positions for sacroiliac joint pain relief, there are still other things you may want to consider to keep your sleep quality top-notch.
Good Quality Pillow and Mattress
If you’re sleeping on a dusty old spring mattress that makes you wake up from your slumber feeling stiff, it may not be the best option for your SI joint pain. Many companies out there produce high-quality foam or memory mattresses that can benefit you - you’ll want to find the right level of firmness that suits you.
Pillow height also matters depending on your preferred position. The firmness of your pillow along with its ability to contour to your neck can also optimize your sleeping position. Overall spinal alignment is key here!
Some characteristics in the room you sleep can affect your overall rest quality. These include cleanliness, how dark it is (you’ll want it as dark as possible), and even your room’s temperature.
- Avoiding alcohol/caffeine close to bedtime
- Sleeping at the same time every day
- Dim lighting/avoiding blue lights after sunset
- Light stretching routine
- Using high-quality CBD products
- Self-massage on sore muscles to relax (or have your partner do it for you!)
Sleeping Position for Sacroiliac Joint Pain Relief: FAQ
What helps with sacroiliac joint pain while sleeping?
As a recap from the above sections: proper positioning, a good mattress/pillow setup, an awesome nighttime routine, and lifestyle modifications during the day can hopefully get your SI joint pain under control at night!
What irritates sacroiliac joint pain?
What can irritate SI joint pain are the habits or actions that got you in this position in the first place. Some of these include poor posture, heavy lifting, or impact/trauma/pressure on the joint. Other causes include pregnancy or arthritis.
How do you calm an inflamed sacroiliac joint?
It may be an obvious answer, but rest is the easiest intervention when you feel pain or discomfort in any area, not just for your SI joint. You can also try things such as heat therapy, acetaminophen or ibuprofen, massage, and CBD products. These actions will help if you are experiencing pain at the current moment.
Other things you can still try down the line are supportive devices (joint belt/brace for extra support), physical therapy, and corticosteroid injections (of course through your healthcare provider).
What movements should you avoid with SI joint pain?
This is a great question to explore. While the apparent answer may be to avoid any movement that causes pain, let’s dive deeper into this topic.
Twisting Movements: Remember that your SI joint is a stabilizer and shock absorber for movements between the upper and lower body. Twisting may be difficult and cause stress if you’re still in the healing stages.
Bending from the Waist: Remember to bend at the knees (almost as if you’re squatting!) if you need to since bending at the waist (especially with heavy objects) can stress your SI joint.
High-Impact Activities: The SI joint is always involved with walking, running, standing, and lifting (yes, this sounds like everything we do) so refrain from any highly intense or repetitive activities that involve these actions for now.
Prolonged Sitting/Standing: Remember to take breaks to stretch and rest your SI joint, as anything prolonged can cause unnecessary stress.
Walking on Uneven Surfaces: Uneven surfaces make our SI joints work harder in terms of stabilization. Avoid this if possible.
Crossing Your Legs: Crossing your legs can potentially cause pelvis misalignment and aggravate your SI. Sitting with both feet on the ground will help - if you have to sit in an office chair for longer periods than you’d like, an ergonomic chair with proper lumbar support is something worth checking out.
Sleeping Position for Sacroiliac Joint Pain Relief: Conclusion
I hope this article has helped you to find a restful night’s sleep despite wrestling with sacroiliac joint pain. While there are some adjustments and other things to consider around your nighttime routine, we all know how important sleep is for rest, recovery, and feeling our overall best!
Just like other pain conditions, the menu of interventions is not a one-size-fits-all and may require some experimentation to see what works best for you. Don’t hesitate to see a health professional as there are surely other strategies that aren’t discussed on this page. Here’s to you getting a night of pain-free sleep!
 Raj, M., Ampat, G., Varacallo, M. Sacroiliac joint pain. Stat Pearls, 2023.
 Dydyk, A., Forro, S., Hanna, A. Sacroiliac joint injury. Stat Pearls, 2023.
 Hansen, H., Helm, S. Sacroiliac joint pain and dysfunction. Pain Physician, 2003. https://www.painphysicianjournal.com/current/pdf?article=MTM3&journal=15