Have you ever had pain that feels like lower back pain, but it doesn’t feel quite the same. Almost like it’s in that tricky spot just below your lower back? In between your buttock and your tailbone. Pain like this could be caused by something we call Sacroiliitis, which is inflammation of the sacroiliac joint. It typically causes pain on one side that feels worse when you stand, walk or climb stairs.

It can be tricky to distinguish between lower back pain and sacroiliac joint pain, but after reading this, you’ll understand the difference.

What exactly is a sacroiliac joint?

Your sacroiliac joint is the place where your pelvis bone (ilium) connects with the lowest part of your spine (sacrum). It is also called an SI joint or commonly referred to as SIJ. A good way to locate your SI joint is to look for the two dimples just below your lower back area.

  • Ilium is a Latin word meaning “groin” or “flank”. There are two ilium bones forming the posterior (back) part of your pelvis bone.
  • Sacrum is derived from the Latin words os sacrum which means “sacred bone”. This is a triangle-shaped bone found just below the lumbar vertebrae.

The two ilium bones connect to the sacrum. One on the left and one on the right, forming two sacroiliac joints.

The connection surface between these bones are quite flat and doesn’t allow a lot of movement. This is ideal, because the SI joint provides a lot of stability to the spine and the pelvis. Even though this joint doesn’t move much, it still has synovial joint fluid inside. This provides nutrition to the bones and helps to reduce friction inside the joint.

Ligaments and muscles

Some of the strongest ligaments in the human body can be found around the sacroiliac joint. They connect the spine, the sacrum and the ilium and attach to the bones at different angles. This provides extra stability.

The SIJ is an important connection point for many muscles:

  • Gluteus maximus, minumus and medius (buttock muscles)
  • Erector spinae (spinal muscles)
  • Psoas (hip muscles)
  • Quadratus lumborum (back muscles)
  • Piriformis (buttock muscles)
  • Abdominal obliques (stomach muscles)
  • Pelvic floor muscles

What does it do?

Stability is the main function of the SI joints.

  • That is reason why the strongest ligaments in your body are found there.
  • Together with the spine, the SI joints help to support the weight of the entire upper body.
  • It is the connection point for the lower body and upper body because it connects the hip and lower back to each other.
  • The muscles that attach onto the SIJ don’t really provide movement to the SIJ. Instead, they help to provide stability.
  • Together, the bones, muscles and ligaments help with core stability. This ultimately protects your spine.
  • When you walk, run or jump, these joints provide stability as you transfer weight from one leg to another.

The SIJ joints might not be well known, but if you didn’t have them, you’ll be without a backbone.

I think I have sacroiliitis. How did it happen?

Itis means “inflamed”. So, sacroiliitis is inflammation of one or both of your sacroiliac joints. It is just a broad term used to describe a painful state of the SIJ.

Inflammation isn’t always bad

Inflammation is part of the body’s defense mechanisms. It is the process by which your immune system recognizes harmful and foreign stimuli and begins the healing process. Ultimately helping you to recover.

Why is inflammation causing me pain?

Abnormal movement of the SIJ, causes excessive translation and shifting of the joint surfaces over one another. This includes either too much or too little movement. It leads to swelling and a build up of joint fluid inside an already tight-fitting joint. The swollen tissues inside or around the joint now push against sensitive nerve endings and this sends messages of pain to your brain. Other biochemical substances are released which increase the sensitivity of the tissues in the inflamed area. Now, a simple movement or a little bit of pressure can feel really sore.

Vicious cycle

Muscle spasms form in the multiple muscles around the SIJ. This happens because the muscles are trying to protect the underlying joint. But, this leads to more pain and stiffness, resulting in less movement. So, you become stuck in a cycle of being in pain when you try to move and feeling worse because you can’t move. And unfortunately the inflammation and swelling needs movement and circulation to improve and heal.

A blurred area of pain

Sacroiliitis easily feels like lower back, buttock or hip pain. It occurs in conjunction with lower back or hip problems. You might be confused by this pain blurring from one area into another, but any one of our physiotherapists at Well Health Pro can help you to distinguish where your pain is coming from.

Causes of sacroiliitis

Hypermobility (too much movement) in the SI joint

  • Pregnancy (due to relaxin hormone)
  • Injured, or sprained ligaments (car accident or hard fall)
  • Muscle imbalances (scoliosis)
  • Altered gait patterns (leg length difference)
  • History of having polio or stroke/paralysis
  • Repetitive stress to the SI joint (extreme sports or physical labor)
  • Lower back surgery/fusions (SIJ compensates for not enough lumbar movement)

Hypomobility (too little movement) in the SI joint

  • Rheumathoid arthritis
  • Ankylosing spondilitis
  • Age-related degeneration
  • Osteoarthritis
  • Previous fractures to pelvis or sacrum

Symptoms of sacroiliitis

Tests that you can do at home to see if you have sacroiliitis

  • Lie on your back with both legs straight.
  • Slide your right foot up towards you until you can put your right foot on your left knee.
  • Now, lower your right knee outwards as if you are trying to stretch your inner thigh.
  • Lower your right leg and repeat the same movement with your left leg.
  • Compare what you felt in both legs and your lower back/sacroiliac joint.
  • Pain and stiffness in your lower back or sacroiliac joint may indicate sacroiliitis.
  • Stand in front of a step.
  • Climb up the step with your right leg.
  • Climb back down and then climb up the step with your left leg.
  • Compare what you felt, especially as you lean forward and push upwards.
  • Pain or stiffness in your lower back or sacroiliac joint may indicate sacroiliitis.
  • Lie on your back with both legs flat.
  • Pull your right knee toward your chest (about 90 degrees).
  • Put both hands on top of your right knee.
  • Give as much pressure as you can downwards (towards the bed) slowly taking up the slack for 4 seconds.
  • Hold the pressure for 5-10 seconds.
  • Lower your leg back down.
  • Repeat the same movement with your left leg.
  • Compare what you felt with both legs.
  • Pain or stiffness in your lower back or sacroiliac joint may indicate sacroiliitis.
  • Lie down on your back.
  • Put both hands on your hip bones (the ones that you can feel sticking out below your stomach).
  • Give pressure with both hands towards your navel.
  • If you feel a relief of your pain and stiffness in your lower back or sacroiliac joint, it could be sacroiliitis causing it.

How severe is my sacroiliitis?


You feel pain, but you’re not really limited by it. The inflammation of the SIJ is still minimal and it only bothers you when you’ve put repetitive pressure on it, like being on your feet for a long time like standing in a que for too long or after jogging. At this stage the pain is still well localised and you only feel it on one side.


Now, you feel pain more often. The inflammation caused enough swelling and pressure inside the SIJ, that each time you put pressure on it, it is sore. You feel really limited by it, because the more you do, the more it hurts. The pain starts spreading to your buttock, leading to a constant muscle spasm and tightness. Stretching your hips eases the pain for a short while. Stiffness is more prominent in the mornings, and after getting up from sitting. The pain tends to get worse the longer you stay in a still position, especially sitting and standing.


In this stage, your pain is constant deep dull ache and excruciating. It spreads to your lower back and even to your other SI joint, making the area of your pain feel much bigger. The muscle spasms in your buttock and lower back lead to nerve irritation and this causes radiating pain down your leg. Each step gives you sharp pain and makes your leg feel wobbly and weak. Even lying down on your side, worsens the pain.

Diagnosis of sacroiliitis

Physiotherapy diagnosis

Our physiotherapists are experts in human anatomy and movement, with the necessary experience to diagnose sacroiliitis as the cause of your back pain. We fully understand how your spine and pelvis should move and how important the SIJ is in providing spine stability. We can accurately differentiate between pain coming from your hip joint, lumbar spine and sacroiliac joint. Our physiotherapists is the best at diagnosing this type of problem.

During your physiotherapy evaluation, we will stretch and stress your hip joint and spinal joints. This way we can evaluate range of movement and test for pain provocation. Once we’ve pinpointed the culprit and prioritized the hierarchy of structures that must be treated, we’ll get right on it.


X-rays shows the integrity and alignment of joints and bones in your spine. So, this allows us to see if something is wrong with the structure of the sacroiliac joint and it’s connecting surfaces.

Your physiotherapist can refer you to get x-rays taken if necessary.

Diagnostic ultrasound

Sonar is not the best tool for investigation with sacroiliitis. Diagnostic ultrasound shows the presence of a muscle tear (muscle strains), inflammation, swelling or simply increased contraction of a muscle (muscle spasms).

If you need an ultrasound, your physiotherapist will refer you.


An MRI scan can image all of the structures in your spine, including soft tissue, discs, nerves and bones. However, an image like this is expensive and you need to be referred by a specialist. If your physiotherapist suspects anything more than an inflamed sacroiliac joint, you will be referred to the right specialist.

Why is the pain from my sacroiliitis not getting better?

Initially, your sacroiliitis is caused by inflammation and swelling in the joint space, causing pain when you put pressure on it (compress it). Resting seems to help, so you do that more often. Unfortunately your muscles become weaker, joints become stiff and now you compensate by using the wrong muscles at the wrong time further aggravating the abnormal shift in your sacroiliac joint’s connecting surfaces.

It isn’t that easy to avoid putting pressure on your SI joint. Through the day you need to walk, stand up often and maybe climb stairs as well. And before you know it, your pain is getting worse again. These movements cause irritation and pressure in the sacroiliac joint and that leads to more inflammation, which in turn starts up the cycle of pain again. You become stuck in a cycle of pain, not knowing if it is safe to move or not.

Effective treatment of sacroiliitis needs to address the underlying cause. Whether you struggle with a hypermobility or hypomobility type of problem, effective treatment needs to include core strengthening to help improve the stability of your sacroiliac joint. The sooner you sort out exactly what is causing the sacroiliitis, the better. Certain medication might ease the pain, but it won’t prevent the pain from coming back if there is a deeper problem. There is a risk of more critical and possibly irreversible damage if you keep on pushing through your pain.

What NOT to do

  • Long term use of anti-inflammatory medications

  • Manage the pain through medication alone

  • Try to stretch the pain away

  • Walk, run, jog through the pain

  • Do not ignore SIJ pain that gets worse

  • Leave it untreated

  • Use a brace or SIJ belt for longer than a month without guidance

What you SHOULD do

  • Rest as needed
  • Avoid things that worsen your pain significantly, like being on your feet for too long

  • Make an appointment to confirm the diagnosis

  • Finish your treatment and rehabilitation program for better long-term results

  • Do appropriate and safe exercise to help with core strength

Making it worse

  • Getting up from sitting

  • Walking

  • Standing

  • Climbing stairs

  • Running

  • Jumping

  • Driving

  • Working at your computer for long hours

Typical problems that arise when patients come to us with sacroiliitis

Waiting too long and not getting a proper diagnosis

A common problem we see is that patients wait too long before they seek help. By the time they come to us for help, they’ve had pain for months or years. In some cases, they’ve had recurring episodes of pain that they have done nothing about. The longer you wait, the more advanced the problem becomes and the longer it will take to get better.

If you don’t get a proper diagnosis from the start, it wastes time. If someone is treating your sacroiliitis and not looking for the underlying cause, it’s like putting a plaster on the problem. This is ineffective, and your symptoms are likely to return.

Trying out, but not completing different forms of treatment

Often, patients take anti-inflammatory medication in the hopes that it will ease their pain. When they feel somewhat better, they stop the medication and try to get back to a normal routine. But often their symptoms come back because they haven’t restored the movement of their sacroiliac joint.

Using a back brace or SIJ belt might be useful in the beginning to give you the stability you need, but it won’t be a long term solution. The longer you use it, the more dependent you become on it. In fact, your core muscles should be giving you that stability.

And then, a lot of people stop their treatment halfway through because they feel better. You need to address the deeper problems like hyper- or hypomobility or poor core muscle strength. That is the best long-term solution. Patience is key.

Resting too much or too little

It’s a natural response. But, resting too much causes your body to decondition and leaves you feeling weaker. Whereas, too much movement, exercise or stretching leaves you with even more pain and inflammation. People tend to stretch or foam roll to ease the stiffness, but you can easily overdo it. Finding the balance between resting and doing safe movements is key. Let us help you get the right treatment for your sacroiliitis and prevent it from stopping you in your tracks.

Physiotherapy treatment for sacroiliitis

We provide effective treatment for sacroiliitis. We understand that you want pain-free movement again so that you’re able to stand and cook, go for a walk with the dogs or run around with your grandkids. That is why we are here to guide you and tell you what kind of treatment you need. As physiotherapists we implement a very effective and structured plan of action that treats all the aspects of your painful sacroiliac joint. Our treatment helps to decrease inflammation in order to get your movement and strength back to normal.

First we’ll confirm your diagnosis by testing your SIJ movements and eliminating other possibilities like pain coming from you lumbar spine. Your first goal is to protect it from further injury and create the ideal environment for it to start healing. Your techniques like mobilizations restores the SIJ movement if it’s moving too little, or we limit excessive joint translation using strapping and taping. We’ll control inflammation using laser and get rid of the guarding muscle spasms over your hip and lower back using various soft tissue treatments.

While we’re busy restoring the SIJ motion, we’ll focus on getting your core muscles to stabilize the sacroiliac joint, together with load displacement and firing pattern of your hip and lower back muscles. This requires a skilled professional to monitor and adapt your program as you progress through the stages of healing. As the SIJ movement improves, we’ll strengthen into the new available range.

Phases of rehabilitation

1st Phase: (Week 0-1)

The first order of business will be to get your levels of inflammation and pain under control. Then we can work on mobility, so that your normal day-to-day movements feel easier. Initially, it might be necessary to use a back brace or SIJ belt to support your sacroiliac joint. Pain medication is very helpful during this phase, to ease the initial pain and stiffness.

Our goal during this phase is to move within your limits of pain and avoid continuous flare-ups of inflammation.

2nd Phase: (Week 1 – 2)

With a lower intensity of pain, our goal will now be to improve your range of movement. Now you can push yourself a little bit more and get your sacroiliac joint to slowly adapt to the load again. Often, stiffness sets in after the pain settles. So, we would make sure your spinal and hip range of motion get back to normal. For this we use joint, neurodynamic and soft tissue mobilisations to gain range of movement.

Everyday things like getting up from sitting and turning around in bed should become easier in this phase of treatment.

3rd Phase: (Week 2 -3)

Walking around with sacroiliitis is bound to affect your walking pattern. Often, just getting used to putting pressure through the joint again is an exercise in itself. You’ll need to work on joint loading and not being afraid to put all of your weight on only your sore side. Thereafter, you’ll find it’s much easier to walk without any problems.

This phase will focus on single-leg and weightbearing exercises.

4th Phase: (Week 3 – 4)

An important part of sacroiliitis treatment is core strength. That will be the foundation of all your strengthening. It gives stability to your sacroiliac joint, which will ultimately be the best longterm benefit.

5th Phase: (Week 4 – 6)

Gradually returning to your routine and getting used to the intensity of your usual activities is a big part of your recovery. We need to determine if you are ready to return to fully working and training without any painful flare-ups. Even with repetitive movements throughout your day (like getting up and walking around in your office) or more load (like running), your sacroiliac joint must be able to carry the load. Your physiotherapist will guide you to re-engage in safe increments, and help you with further strengthening.

Getting you back to playing with your kids, hiking, running or skipping is the ultimate goal.

6th Phase: (Week 6 and on) 

By now you should be able to jump, lift weights or do backbends in the yoga class, but there are some specific stress tests that you should be able to do. This allows us to make sure the structure of the SIJ and surrounding muscles can handle stretch stress, maximum load, and compressive forces.

Now we can sign off on your recovery, knowing you’re safe.

Recovery period

Sacroiliitis takes anything from 6 weeks to a few months to treat, depending on the severity of your symptoms. You will need physiotherapy treatment twice a week for the first two weeks to work through the initial phase of treatment. The aim is to decrease inflammation and get your SIJ movement back to normal. After this, your treatment sessions can be spread out to once a week or once in two weeks. This is when you work on stability and strength and load displacement. Remember, you only spend an hour at a time with your physiotherapist. How fast you recover is greatly be up to you. At the end of your recovery process, your sacroiliac joint should be able to handle the demands of everyday life again.

Other forms of treatment for sacroiliitis

  • Your doctor might prescribe anti-inflammatory medication or give you a cortisone injection to treat sacroiliitis. Both of these medications gives temporary relief to the inflammation and pain. However, it isn’t the solution to your problem. Once the effect of the medication wears off, your pain could simply return.
  • Getting your back ‘aligned’ or ‘clicked’ in the hopes of improving the pain will not improve the inflammation or the state of the surrounding soft tissue and muscles. It could even trigger an increased inflammatory response.
  • A biokineticist will be able to help you in the final stages of your rehabilitation programme or to get you back to actively training for your sport.
  • Wearing a back brace or SIJ belt could be useful if your pain is severe. Even though the support can help, it is something you could get dependent on. Active movement is still important.
  • Stretching or foam rolling your back might ease some of your pain. But, forcing your spine into painful positions in the hopes of stretching or pushing the pain away, could actually worsen your inflammation response.

These treatments can be used in conjunction with physiotherapy. And at Well Health Pro, our physiotherapists will guide you in choosing the right treatment for your sacroiliitis.

Is surgery a treatment option for sacroiliitis?

Surgery is not something you need to consider straight away. If your pain is caused by sacroiliitis and it doesn’t respond to non-surgical treatment within 3 months, surgery could be an option. Discuss this with your physiotherapist and make sure you have the necessary information about the risks, expenses and long recovery time associated with surgery to your spine.

Before any surgery is done, an MRI should be taken to confirm the diagnosis. You would have to see a surgeon to discuss the results and surgical recommendations. A sacroiliac or lumbar joint fusion is one type of surgery that can be done for sacroiliitis. During this procedure the lumbar and/or sacral joints are fused together with pins and screws. After surgery, you have to wear a back brace for 2-6 weeks (depending on the procedure). And you have to comply to the specific doctor’s aftercare routine, like not being allowed to sit for a few weeks.

Regardless of which type of surgery you get, you are only halfway to a successful recovery. The rest of the process includes strengthening and letting your body adapt to the change. Physiotherapy after spinal surgery is vital to get you back to top form.

What else could it be?

  • Lumbar Facet joint pain – especially painful to bend backwards or sideways. Lower back and sometimes buttock pain.
  • Sciatica – burning, tingling type of pain that can spread from your buttock and lower back down your leg.
  • Ankylosing spondylitis – this is a type of inflammatory arthritis that can cause some of the bones in your spine to fuse. It makes the spine less flexible and can result in a hunched posture.
  • Buttock muscle strain – buttock pain that feels worse with movements like walking, climbing stairs or running.
  • Hip joint pain – pain and stiffness in the buttock and groin area that can spread down your thigh. Difficult to bend your hip and cross your legs

Also known as

  • SIJ pain
  • Inflamed sacrum joint
  • Locked SI joint
  • Painful and inflamed SI joint
  • Lumbosacral pain
  • Inflammatory sacroiliitis