FAQs on Sacroiliac (SI) Joint Injection in Atlanta


A sacroiliac (SI) joint injection involves instillation of a corticosteroid or other medication directly into one of the SI joints, which are located on either side of the tailbone (sacrum). SI joints connect the tailbone to the pelvis.

What is the purpose of the SI joint?

When the steroid is injected into the SI joint, this reduces the swelling and inflammation of tissue in and around the joint space. In turn, this eliminates or reduces pain and other symptoms associated with the joint irritation and inflammation of surrounding structures.

What medications are used for this procedure?

The actual injection only takes around 5-10 minutes, consisting of a mixture of a local anesthetic and corticosteroid substance. Occasionally, phenol is used during the procedure, to destroy nerve roots. The procedure does not require general anesthesia, but some patients choose to receive some sedation, which is given through an intravenous (IV) line.

Will the SI joint injection hurt?

The SI joint injection involves the insertion of a needle through the skin and deep tissues, so there is some pain involved. However, the doctor will numb these structures with a local anesthetic using a small needle beforehand.

How is the sacroiliac joint injection performed?

The SI joint injection is done with the patient lying on his/her stomach under x-ray guidance. The patient is monitored with EKG, oxygen saturation device, and blood pressure cuff. The skin is cleansed with an antiseptic solution, and the tissues are numbed. The needle is placed into the SI joint, and medications are then injected. Once the injection is complete, the needle is removed and a bandage is applied.

What should I expect after the SI joint injection?

Immediately after the procedure, you may feel that your pain is decreased or eliminated due to the local anesthetic. Once this medication effect wears off, you may experience soreness at the site for 24-48 hours. The steroid medication usually kicks in after 2-3 days.

If you receive sedation, you must have someone with you to drive you home. We advise patients to rest for the remainder of the day and apply ice to the affected area a few times each day. You will be permitted to return to normal activities the next day.

How many sacroiliac injections will I need?

If the first injection does not relieve your pain and other symptoms in 2 weeks, the doctor may recommend a subsequent SI joint injection. If you respond well to these injections but continue to have returning pain, the doctor could recommend a third injection. We only perform 3 injections in a six-month time period.

What are the risks and side effects of the SI joint injection?

Because a corticosteroid is used, certain side effects could occur, such as slight weight gain, water retention, and elevated blood glucose. However, these side effects are only temporary. The SI joint injection is a safe procedure, but rare complications do occur. These include prolonged pain at the injection site, infection, and bleeding.

Do SI joint injections work?

Researchers evaluated the therapeutic efficacy of SI joint blocks in 2009. They found that 67% of patients reported significant pain reduction that lasted for longer than 6 weeks. According to the American Society of Interventional Pain Physicians (2013), there is much evidence that these injections show 75-100% pain relief when compared to placebo treatments.