Sacroiliac Joint Pain

Sacroiliac (SI) joint is the joint in the bony pelvis that connects the pelvic bone (ileum) to the lowest part of the spine (sacrum). It is a small and very strong joint, reinforced by strong ligaments that surround it. SI joint does not have much motion, and it transmits all the forces of the upper body to the pelvis (hips) and legs, acting as a shock-absorbing structure. Whenever an SI joint is irritated or injured, the resultant joint dysfunction may cause pain in the lower back and legs.

Symptoms:

The pain is typically felt on one or both sides of the lower back and/or buttocks, and can radiate down the leg(s). The pain usually remains above the knee, but at times pain can extend to the ankle or foot. The pain is similar to sciatica, or pain that radiates down the sciatic nerve and is caused by a radiculopathy. The pain may also radiate into the groin area.

Causes:

• Different types of arthritis that affect all the joints of the body can also affect the sacroiliac joint causing pain.
• Too much movement (hypermobility or instability)
• Too little movement (hypomobility or fixation)

Diagnosis begins with a complete history and physical exam. X-rays can give your doctor an idea about how much wear and tear has occurred in the SI joint. The most accurate way of determining whether the SI joint is causing pain is to perform a diagnostic injection of the joint under fluoroscope. X- rays or MRI of the lumbar spine and hips are also helpful to rule out problems in these areas that may act and look like SI joint dysfunction. Laboratory tests may be ordered if there is any question whether you might have an infection or some type of arthritis affecting multiple joints.

Treatment:

Non-surgical options:

• Physical therapy
• Chiropractic care
• Non-steroidal anti-inflammatory medications.

Injection Therapy:

• A series of steroid injections to reduce inflammation
• Sacral lateral branch block (SLBB), which is a diagnostic block, followed by Radiofrequency ablation (RFA) of the SI joints.

Surgical treatment:

• In case of failure of other conservative treatment approaches, surgical fusion of the SI joint can help manage the dysfunction.