Pain in your lower back can be caused by many things including muscle pain, soft tissue pain, or joint pain. The sacroiliac (SI) joints can also be a cause of lower back and arthritis pain. Similar to the knee, the SI joint contains cartilage which degenerates over time. Saroiliac pain can cause different forms of arthritis including: osteoarthritis, ankylosing spondylitis, psoriatic arthritis, and gout.
When you feel pain in your lower back or hips, the pain can originate from muscles, soft tissues like tendons and ligaments, or joints.
But it’s not just the joints of the spine or the large hip ball-and-socket that may be the source of the problem—there’s also a pair of joints that can cause symptoms called the sacroiliac (SI) joints.
The SI joints connect the base the spine with the pelvis on both sides of the body. They’re strong, supportive joints that don’t move much, but they still have the same structure as more common joints in the body, like the knee. This means the SI joints have cartilage, which can degenerate, and synovial fluid, which can become inflamed—causing pain and inflammation in the joint.
Symptoms of SI joint dysfunction and sacroiliitis
Pain in the sacroiliac joint is known as SI joint dysfunction (sometimes also SI joint syndrome, disease, or disorder). Inflammation in the SI joint is known as sacroiliitis.
Regardless of the terms used to describe it, sacroiliac joint pain and inflammation cause these symptoms:
- Pain in the lower back, buttocks, hips, and/or groin
- Pain that radiates down the legs (similar to sciatica)
Types of arthritis that can cause SI joint pain
Symptoms in the SI joints can be the calling cards of several types of arthritis, including the following:
Age, excess weight, and repetitive motion can all take a toll on the SI joint’s cartilage, causing it to wear away and bony growths to form and irritate the surrounding tissue.
This form of arthritis causes inflammation where ligaments and tendons attach to bone, which often affects the spine. In fact, SI joint pain is often the first symptom of ankylosing spondylitis.
Continue reading the full article from Spine Health here.