Sacroiliac Joint Injection

I. Introduction

• The Sacroiliac Joint Injection (SIJI) is a procedure targeted toward a symptomatic or painful sacroiliac joint thought to be responsible for a patient’s low back pain. The joint is injected and anesthetized with the intent of relieving this pain.
• The SIJI delivers a low volume of concentrated medication directly into the affected joint space.
• Low Back Pain (LBP) is often multifactorial and difficult to diagnose because the symptoms overlap considerably with those of other degenerative disorders of the lumbar spine and hip.
• The SIJI is useful in both the diagnosis and the treatment of LBP; therefore, it is both a diagnostic as well as a therapeutic procedure. In other words, if we inject a medication within the suspected joint space and the pain improves, we are fairly confident that this joint is responsible for the pain; conversely, if we inject a medication and the pain is no better, this implies that this joint is likely not responsible for the pain.

II. The Sacroiliac Joints

• The Sacroiliac Joints are the joints that connect the spine (lumbar spine) to the pelvis. There are two SI joints, a right and a left, and they are located in the back at the base of the spine.
• Like any other joint in the body, can become diseased, and thereby become painful.
• Arthritis is probably the most common cause of SI joint pain. Arthritis is a degenerative, inflammatory condition that over time results in loss of joint cartilage, bone overgrowth (‘osteophytes’ or ‘spurs’), erosions of the joint, and ultimately instability of the joint itself may occur in this joint.
• The sacroiliac joints and their surrounding tissues are lined with nerves. As this degenerative, inflammatory condition progresses, the nerve endings become irritated and inflamed; this produces the sensation of pain. Any and all of this degenerative process may be painful.
• The primary role for imaging studies prior to the procedure is that while arthritis is probably the most common cause for sacroiliac joint pain, other rare conditions need to also be considered, and imaging helps to evaluate for this.

III. Sacroiliac Joint Pain

• Pain arising from the sacroiliac joints is often difficult and troublesome to diagnose
• SI join pain may be unilateral or bilateral, and may include the following:
  • i. Groin pain
  • ii. Sitting intolerance (can stay seated for only short periods of time)
  • iii. Referred numbness, burning or tingling in the buttock or lower extremity
  • iv. No associated radiculopathy

IV. Patient Selection

• Patients who have chronic low back pain without radicular symptoms are candidates for SIJI.
• Routing imaging prior to this procedure typically is limited to plain film X-RAYs, but may include CT and/or MRI scanning.

V. Procedure

• The procedure is explained to the patient, questions are answered and informed consent is obtained.
• The patient is placed prone (stomach down) on the fluoroscopic table or CT scanner and the lower back is sterilely cleansed with povidone-iodine (Betadine) and alcohol.
• The exact level is then locate, and the skin overlying this area is anesthetized (numbed) with lidocaine.
• A needle is sterilely advanced into the lower ½ of the SI joint.
• Typically, as small amount of water-soluble contrast (dye) is injected to confirm proper needle tip position.
• Once this is confirmed, a mixture of anesthetic (lidocaine or bupivacaine) and anti-inflammatory medication (steroid) is injected.
• The needle is slowly withdrawn
• This procedure may be performed with either CT or Fluoroscopic guidance.