Lower back pain affects 80% of Americans at some point in their lives. In The United States it is the most common cause of job-related disability, and a leading contributor to missed work.  Sacroiliac Joint Dysfunction or “SI Joint Pain” is a common cause of low back pain. This joint is shaped like an ear, and is located in the buttock region between the sacrum and iliac bone.  The SI joint is a synovial joint stabilized by seven ligaments.

SIJ pain is more common in females.  However, males can also develop this condition.  SI joint dysfunction can be secondary to “locked joint” or a joint that is loose or unstable.  Women during pregnancy can experience SI Joint pain due to the release of a hormone called “relaxin”  that creates instability (unstableness) within the SI joint.    Repetitive bending and twisting activities can contribute toSIJ dysfunction.  Other common causes include: sports related injuries, rear end motor vehicle accidents, and falls onto the buttock.   The most common symptom is isolated pain in the buttock.  Frequently patients will have pain that refers into the groin or into the back part of the thigh.  Rarely does the pain extend below the knee.  In addition, patients can experience secondary muscle spasms in their low back and buttock.  Pain from SI joint dysfunction is brought on with rising from a seated position, climbing or descending stairs, riding in a car for long periods, sitting or lying on the painful side, turning in bed or getting in and out of a car. For athletes this can occur with extreme loading on one leg, heavy lifting, performing fast rotation like in golf or landing/falling while skiing.

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