Sacroiliac (SI) joint dysfunction is a lesser known musculoskeletal problem that is easily confused with hip or spinal pain, due to its location within the body. If left undiagnosed and untreated, it is possible to experience additional problems beyond pain.

Joint Fusion

For some people, the pain of SI joint dysfunction is caused by decreased movement of the joint or even fusion. This is often due to underlying conditions, such as ankylosing spondylitis. Since the SI joint is responsible for absorbing force from the upper-body during activities such as sitting, standing, and walking, the joint may feel stiff and the joint surfaces may eventually become damaged due to increased friction. Decreased motion at the SI joints can be more difficult to treat beyond using anti-inflammatory medications or injectable steroids to reduce pain.

Pelvic Instability

The other reason for SI joint pain may be too much motion at the joints (hypermobility). There are a large network of ligaments responsible for holding the SI joints in place. The ligaments can become weakened due to the expansion of the pelvis during pregnancy and childbirth, injuries, or inflammation. In the case of pelvic instability, some non-invasive treatments may be helpful, such as the use of anti-inflammatory medications.

The use of a SI belt may provide relief since it is wrapped snugly around the pelvis and helps to prevent hypermobility of the entire pelvis. With severe damage, often due to injury or chronic inflammatory processes, surgery may provide better long-term relief. The surgical approach consists of using metal plates to hold the SI joints in place, which constricts excess movement. In some cases, the addition of a bone graft may be necessary to help the bones fuse together.


Excess motion of the SI joints and/or inflammation may irritate the sciatic nerve. Previously, sciatica due to SI joint dysfunction was dismissed as a problem, since the SI joints do not come into direct contact with the nerve. There has been a resurgence of interest in the SI joints as a cause of sciatica, instead of purely associating sciatica with nerve compression or conditions of the lumbar spine.

SI-related sciatica is relatively easy to diagnose and differentiate from other causes. An injection of steroids and lidocaine into the SI joints would bring relief of sciatic pain if SI joint dysfunction is the underlying cause. Lidocaine is used for immediate pain relief, which allows testing of the SI joints immediately after the procedure and steroids provide several months of pain relief.

Although SI joint dysfunction is often misdiagnosed or overlooked as a serious problem, the impairments can cause considerable pain during daily activities and lead to significant disability. If you are experiencing lower back and/or buttocks pain, make sure to ask your doctor (like those at The Advanced Spine Center) to thoroughly evaluate your SI joints.