The sacroiliac joints are the connections between the sacrum at the base of the spine and the ilium bones of the pelvis. If you take both of your hands and place them on the narrowest part of your waist then slide them downward until they are resting on top of the large crest of bones that wrap from back to front, you have found your ilium bones. The pelvis which connects the spine and the legs is formed by two halves, each made up of three bones.

The sacrum itself is a flat, spade shaped bone near the base of the spine. It is positioned below the lumbar spine and above the coccyx. The sacrum is composed of five individual vertebrae that eventually fuse into a solid mass of bone beginning in the 2nd- 3rd decades of life. On occasion some people are born with six sacral vertebrae or only four. Many muscles cross from the bony sacrum to the pelvis and the femur bone of the thigh.

Where the flat sacral bone meets the ilium on either side is called the sacroiliac joint. The articulation is enclosed by a fibrous joint capsule and filled with a lubricating fluid called synovial fluid. Several ligaments span between the sacrum and the ilium further stabilizing the bony connections.

WHY IS THIS JOINT SO IMPORTANT?

Aside from acting as the only bony connection between the spine and pelvis, the SI joint’s main job is to stabilize this bony connection and to reduce the effect of forces traveling up the legs. While the joint is quite stable, it is capable of moving very small amounts as it absorbs the forces that travel up the legs toward the spine.

SACROILIAC JOINT PAIN

SI Joint Pain can have a few different causes:

• SI joint dysfunction
• Hypermobile SI joint (excess motion)
• Hypomobile (stiff) SI joint
• Slight mispositioning
• Sacroiliitis
• Inflammation of the SI joint
• Arthritis
• Pregnancy
• Pregnancy hormones can cause laxity and hypermobility in SIJ ligaments
• Trauma

• Pain that is sharp, stabbing or shooting
• Unilateral or bilateral buttock pain and/or midline lower spine pain
• Pain that radiates into the buttock and back of the thigh but not below the knee
• Local tenderness over the involved SI joint

• Prolonged standing
• Running
• Taking long strides
• Standing with more weight on one leg than the other
• Climbing stairs
• Lying on the side of pain
• Sitting too long

If you decide to work with a physical therapist to help correct your sacroiliac joint pain issues, your entire treatment plan could consist of around 8-20+ different physical therapy sessions that will each last 60-90 minutes. Once you complete your customized physical therapy treatment plan, you will be able to continue to do the prescribed stretches and exercises utilized during your PT sessions yet in the comfort of your own home.

PHYSICAL THERAPY FOR SI JOINT PAIN

Physical therapy is often a first line treatment for SI Joint pain. At times anti-inflammatory medications may be recommended by your doctor if acute inflammation is a primary contributor to your pain. Addressing the root cause is the main goal of physical therapy treatment to reduce pain and discomfort. When the root cause cannot be fixed such as when pain is caused by arthritis, your PT will work to minimize symptoms by addressing other factors that may contribute to pain. Common treatments for SIJ pain include:

• Modalities like heat or cold to minimize SIJ inflammation
• An SIJ belt may be prescribed in the acute phases to reduce inflammation and pain
• Exercises to maximize the strength of the glute and core muscles to support the SI joint
• Low back muscle control and stabilization exercises integrated into dynamic tasks
• Lumbar and SI joint manipulation and mobilization techniques
• Stretching to address shortened muscles