The sacroiliac joint connects the sacrum (triangular bone at the bottom of the spine) with the pelvis (iliac bone that is part of the hip joint) on each side of the lower spine. It transmits all the forces of the upper body to the pelvis and legs. There is not a lot of motion in the joint and it is very strong and stable.
It is not clearly understood why sacroiliac joint dysfunction occurs, although some believe it is due to a limitation in its normal motion patterns and/or misalignment of the joint. Sacroiliac joint (SI joint) pain typically results in pain on one side very low in the back or in the buttocks. Another term for sacroiliac joint pain is sacroiliitis, a term that describes inflammation in the joint.
Sacroiliac Joint Dysfunction Symptoms
SI joint problems are a common cause of low back pain. Additional symptoms may be characterized by the following:
- Pain in the thigh and/or buttock, and possibly pain that radiates down the sciatic nerve, although it rarely radiates into the foot
- More commonly experienced on one side of the body, but may occur on both sides
- More commonly found in young or middle age women.
Treatments for Sacroiliac Joint Dysfunction
Treatment for SI joint pain is most commonly nonsurgical, and is generally focused on reducing inflammation and pain and restoring normal motion in the joint. Nonsurgical treatment may include one or a combination of the following:
- Physical therapy and exercise. See also Exercise for Sacroiliac Joint Pain Relief
- Pain medications (such as acetaminophen or muscle relaxants) and anti-inflammatory drugs (such as ibuprofen or naproxen)
- Use of a pelvic belt to provide stability
- Osteopathic or chiropractic manual manipulation of the sacroiliac joint
- Injections to the sacroiliac joint. The injections introduce pain relieving medication and/or anti-inflammatory medication directly into the joint, and are most successful when done using fluoroscopy. Length and amount of pain relief is variable.
In This Article:
- Sacroiliac Joint Anatomy
- Spine Anatomy Interactive Video
For the rare cases in which the patient experiences chronic, severe pain originating in the sacroiliac joint, surgery to fuse the sacroiliac joint may be an option. The goal of a fusion for sacroiliac joint dysfunction is to properly align the joints and set up the environment to allow them (either one or both of the joints) to fuse together, thus eliminating any abnormal motion.