Sacroiliac Joint Injection for Lower Back Pain

Sacroiliac (SI) joint injection is a minimally invasive procedure that involves injecting a mixture of local anesthetic and/or corticosteroid medication directly into the SI joint.¹Jung MW, Schellhas K, Johnson B. Use of Diagnostic Injections to Evaluate Sacroiliac Joint Pain. International Journal of Spine Surgery. 2020;14(s1):S30-S34. https://doi.org/10.14444/6081 The SI joint is located in the lower back and connects the sacrum to the ilium bone (part of the pelvis).²Raj MA, Ampat G, Varacallo M. Sacroiliac Joint Pain. [Updated 2022 Sep 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. https://www.ncbi.nlm.nih.gov/books/NBK470299 The injection is performed under x-ray or ultrasound guidance to ensure accuracy and precision.

Goals of SI Joint Injections

SI joint injections are used for one or both of the following purposes¹Jung MW, Schellhas K, Johnson B. Use of Diagnostic Injections to Evaluate Sacroiliac Joint Pain. International Journal of Spine Surgery. 2020;14(s1):S30-S34. https://doi.org/10.14444/6081:

• Diagnostic purposes: To help confirm whether the SI joint is the source of lower back pain. This injection is typically performed using only a local anesthetic. If the patient experiences significant pain relief immediately after the injection, it’s a strong indicator that their SI joint is likely the source of their pain.
• Treatment: To help provide longer relief from SI joint pain. Depending on the mixture of medications used, the duration of pain relief varies but can last anywhere from several days to months.²Raj MA, Ampat G, Varacallo M. Sacroiliac Joint Pain. [Updated 2022 Sep 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. https://www.ncbi.nlm.nih.gov/books/NBK470299

When used as a treatment, the goal of this injection is to provide relief from lower back pain caused by SI joint dysfunction, help advance the goals of physical therapy, and improve the patient’s quality of life by improving function in the affected joint.

See Sacroiliac Joint Dysfunction Symptoms and Causes

SI Joint Injections: Types and Uses

Administering a steroid mixture into the joint is a common type of SI joint injection, but there are several other types of injection treatments for SI joint pain, and each type acts through a different mode of action to provide pain relief. 

• Local anesthetic and steroid injections. Local anesthetic and corticosteroid medications are used to reduce inflammation and provide symptom relief to patients with arthritis, inflammatory conditions, and/or acute injuries.³Kao MC, Chuang CW, Hung SK, Pan PT. Diagnosis and interventional pain management options for sacroiliac joint pain. Tzu Chi Medical Journal. 2019;31(4):207-210. http://doi.org/10.4103/tcmj_54_19
• Prolotherapy injections. Prolotherapy is a type of regenerative therapy that involves injecting a medicated solution into the affected area to induce tissue regeneration, promoting healing and reducing pain.⁴Bae G, Kim S, Lee S, Lee WY, Lim Y. Prolotherapy for the patients with chronic musculoskeletal pain: systematic review and meta-analysis. Anesth Pain Med. 2021.16(1):81-95. https://pubmed.ncbi.nlm.nih.gov/33348947
• Platelet-rich plasma injections. Platelet-rich plasma, or PRP, helps repair damaged cartilage, tendons, ligaments, muscles, or even bone using the patient’s own blood and its natural healing properties.⁵Singla V, Batra YK, Bharti N, Goni VG, Marwaha N. Steroid vs. Platelet-Rich Plasma in Ultrasound-Guided Sacroiliac Joint Injection for Chronic Low Back Pain. Pain Pract. 2017;17(6):782-791. http://doi.org/10.1111/papr.12526
• Radiofrequency ablation. Radiofrequency ablation (RFA), also called radiofrequency neurotomy, is a procedure that involves heating a part of a pain-transmitting nerve with a radiofrequency needle to create a heat lesion to prevent the nerve from sending signals to the brain.⁶Manchikanti L, Abdi S, Atluri S, Benyamin RM, Boswell MV, Buenaventura RM, et al. An update of comprehensive evidence-based guidelines for interventional techniques in chronic spinal pain. Part II: Guidance and recommendations. Pain Physician. 2013;16(2 Suppl):S49-S283. https://pubmed.ncbi.nlm.nih.gov/23615883/ Watch Lumbar Radiofrequency Neurotomy Video

A physician with special training in the treatment of musculoskeletal disorders can help identify the type of injection treatment suitable for the specific underlying condition and symptoms.

Common Conditions Treated with Sacroiliac Joint Injections 

SI joint injections are indicated when the source of lower back pain or leg pain is suspected to originate from the sacroiliac joint.

The SI joint can become painful due to a variety of conditions, including¹Jung MW, Schellhas K, Johnson B. Use of Diagnostic Injections to Evaluate Sacroiliac Joint Pain. International Journal of Spine Surgery. 2020;14(s1):S30-S34. https://doi.org/10.14444/6081:

• SI joint dysfunction: Pain caused by excessive or insufficient movement of the SI joint. SI joint dysfunction is the most common cause of SI joint pain and typically occurs due to⁷Hamidi-Ravari B, Tafazoli S, Chen H, et al. Diagnosis and current treatments for sacroiliac joint dysfunction: a review. Curr Phys Med Rehabil Rep. 2014;2:48-54. http://doi.org/10.1007/s40141-013-0037-7:
  • Injury
  • Pregnancy
  • Osteoarthritis
• Ankylosing spondylitis: Inflammatory arthritis that affects the spine and can lead to SI joint inflammation over time

It is important to note that before considering an SI joint injection for lower back pain, it is necessary to rule out other potential causes and try non-interventional treatments first, such as physical therapy or over-the-counter medications. Patients with chronic lower back pain who have not found relief from other treatments, such as oral medication, physical therapy, or manual manipulation, may benefit from SI joint injections.²Raj MA, Ampat G, Varacallo M. Sacroiliac Joint Pain. [Updated 2022 Sep 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. https://www.ncbi.nlm.nih.gov/books/NBK470299

See Treatment Options for Sacroiliac Joint Dysfunction