Sacroiliitis: Cause of Back Pain

Sacroiliitis is a condition characterized by the inflammation of the sacroiliac (SI) joints, which form where the sacrum meets the large pelvic bone (ilium) on each side of the lower back. It is important to distinguish sacroiliitis from sacroiliac joint dysfunction, which involves abnormal range of motion in the SI joints. These conditions can cause each other, but they are not the same.

A common symptom of sacroiliitis is pain in the lower back, buttocks and leg. Leg pain may radiate to the front of the thigh. Stiffness in the hips and lower back may be experienced. Symptoms are generally worsened by sitting or standing for prolonged periods of time. Pain may be worst when waking up in the morning.


Four of the most common causes of sacroiliitis are: spondyloarthorpathy, osteoarthritis, trauma and pregnancy. Spondyloarthropathy is defined as an inflammatory joint disease affecting the spinal column. The cause of this condition is not known for sure, but is thought to be genetic. Osteoarthritis signifies arthritis of the spine, and is caused by the wear and tear joints undergo, either due to simple aging or high levels of activity. Physical trauma to the SI joints, such as incurred during a car accident or hard fall, can cause inflammation in the joints. Finally, the loosening of pelvic joints experienced during pregnancy can cause the SI joints to inflame. Infection is another possible but less common cause.


The key to treating sacroiliitis is to reduce inflammation. Exact treatment methods will depend on the cause of the condition. General treatment techniques include the application of ice and sleeping on the side with a pillow between the knees to keep the joints aligned properly.

Some people may choose to use over-the-counter anti-inflammatory medications like NSAIDS to temporarily help reduce inflammation; others with more severe pain may opt for steroid injections directly into the joint.

These attempts to eliminate inflammation must be coupled with treatments designed to eliminate the cause thereof. If you are affected by a spondyloarthropathy, you may be prescribed a disease-modifying antirheumatic drug (DMARD). Though their exact mechanisms are not known, in some way DMARDS slow the progression of rheumatic disease and increase the likelihood of a good outcome. Immobilizing the joint and reducing inflammation with ice is the first step of treatment, and should be followed by exercise to keep nutrients flowing to the joint and supporting muscles and ligaments strong.

People whose osteoarthritis is causing inflammation of the SI joint may also be prescribed a DMARD. Water therapy is a great way for people with osteoarthritis to stay active and increase joint range of motion without jarring the sensitive joints. Supplements such as glucosamine and chondroitin may be taken to strengthen cartilage and keep joints lubricated. A physical therapist can be of great assistance to anyone with osteoarthritis or spondyloarthropathy.

If an injury has caused sacroiliitis, rest and ice are the primary treatments. After two days, it is essential to get moving again; otherwise, supporting muscles will weaken.

Pregnant women experience a loosening of pelvic joints caused by the hormone relaxin. This loosening makes room for the baby to grow and to be delivered. The change in the range of motion experienced by the SI joint can cause inflammation. After delivery and the necessary period of rest to recover, new moms need to re-strengthen their pelvic muscles and ligaments that support joints. A postnatal Pilates class would help any new mom on her way to recovery.

For every cause, effectively treating sacroiliitis involves three steps: demobilization, reduction of inflammation and remobilization. Whether the result of an injury or part of a larger condition, you can help your SI joint repair itself with ice and targeted exercises. Consider seeking out a physical therapist to guide you in the exercises that are best for you.