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Sacroiliac (SI) Joint Injection/Block

A sacroiliac joint injection both diagnoses the source of low back pain and treats it.

Commonly Asked Questions About Sacroiliac (SI) Joint Injection/Block

A local anesthetic is applied before the SI joint injection is administered. Typically, the injection is performed under X-rays or with ultrasound guidance in the office to ensure the accuracy of needle placement. After the diagnostic injection, the patient assesses pain to determine whether the medication injected actually relieved any pain from the sacroiliac joint. The therapeutic injection is identical except that corticosteroid is included in the injection to reduce inflammation and pain. 

SI joint injections determine whether the patient’s source of pain is indeed the sacroiliac joint or something else. Injections also provide pain relief to the sacroiliac joint. 

Because an anesthetic is used preceding the treatment, pain is minimal, but some may be felt as the needle is inserted into the skin and deeper tissues. 

Patients should follow the treatment with physical therapy with an emphasis on a home exercise program. Depending upon the success of the injection in treating pain, patients may receive up to three additional injections per year.