Sacroiliac joint pain (referred to as SI Pain), is one of the most common causes of lower back pain and can be very persistent and difficult to resolve. In this article we go over some of the most important factors that results in SI pain, as well as ways to prevent and help manage the pain.

The Sacroiliac Joint

The sacroiliac joint or SI joint is right at the bottom of the lower back, between the sacrum and the ilium of the pelvis. The SI joint is a strong, weight bearing joint that is powerfully connected by ligaments. We have two sacroiliac joints, one on either side of the sacrum. Often these joints match each other but are highly variable from person to person. Injury or impairment to these joints is a major cause of lower back pain and SI pain.

SI Pain - Sacroiliac Joint

What is SI Pain?

SI Pain is pain or discomfort originating from the sacroiliac joint. Impairment or sacroiliac joint injury are often referred to as sacroiliac dysfunction. SI Pain is usually a result of a variety of causes and conditions


What are the Causes of SI Pain?

The most common diagnoses of SI pain is sacroiliac dysfunction, this is where the SI joint is under torsion due to structural imbalance. Typically this occurs due to postural injuries, which includes repetitive strain injuries from prolonged seating (for example long drives, with bumpy surfaces), direct impact (for example, falling on your backside), change in your gait can also often lead to SI pain due to the increased stress on the SI joint. Often patients feel that their SI or pelvis is ‘out of place’ and can result in sharp SI pain with sudden movement.

Another common cause of SI pain is sacroiliac joint sprain. The ligaments around the SI joints are extremely powerful. They are primarily in place to prevent excessive movement and at times of sacroiliac joint injury, the ligaments may be sprained, causing inflammation and SI pain.

Sacroiliac joint sprain is also common in pregnancy, as hormones, such as relaxin, are released to allow ligaments to relax and prepares the pelvis and body for childbirth. Relaxation of the ligaments holding the SI joint ultimately leads to an increase in the SI joint motion, which leads to an increase in stress and added pressure on the SI joint as well as more strain on the ligaments, causing tears to the ligaments and producing SI pain.

Like other joints in the body, the SI joints have a cartilage layer protecting the bony surfaces. The cartilage allows for some movement and acts as a shock absorber between the bones. In degenerative arthritis (osteoarthritis) the cartilage can be damaged and start wearing away. Leading to the bones begin to rub on each other and resulting in SI pain as well as stiffness.

There are a number of inflammatory disorders also that affect the SI joints and cause SI pain. These include Ankylosing Spondylitis, Rheumatoid Arthritis, Psoriasis and Reiter’s Syndrome.

Sacroiliac Joint Dysfunction Symptoms

Pain is the most common symptoms.

SI pain usually presents as lower back pain and sometimes hip pain, but can also be felt in the groin and thighs.

The pain may often be difficult to pinpoint.

SI pain is usually worse when you are standing, seating for too long or walking. While symptoms may improve when laying down.

In cases of sacroiliac joint sprain pain is often worse in the morning and after long periods of rest due to inflammation of the surrounding structures.

If the cause of pain is inflammatory in origin, stiffness is often present as well.


What is the Treatment for SI Pain?

Physical therapy can be very helpful in resolving SI pain. Sacroiliac joint dysfunction is often caused by either little to no movement, or too much movement of the joint. A physical practitioner can resolve any torsions going through your SI joint and pelvis. They can also teach you stability and stretching exercises that can help reduce your pain. Yoga and Pilates has also been very beneficial to those with SI pain.

Oral anti-inflammatory medication can help with controlling your pain, but remember that they will only reduce the symptoms and not remove the cause of the SI pain.