Sacroiliac Joint Injection

A Sacroiliac (SI) Joint Block is a minimally invasive injection procedure designed to diagnose and treat pain originating from the sacroiliac joint — the joint that connects the lower spine (sacrum) to the pelvic bones (ilium). This joint bears significant load and stress during standing, walking, or sitting, and may become a major source of chronic low back or buttock pain due to arthritis, trauma, or postural imbalance. By precisely targeting the joint with a local anesthetic and anti-inflammatory steroid, the procedure helps confirm the pain source and provides lasting relief.

Indications

Sacroiliac joint block is typically recommended for:

  • Chronic low back or buttock pain not responding to medication or physiotherapy
  • Pain after falls, lifting injury, or pregnancy
  • Sacroiliac joint arthritis or dysfunction confirmed by imaging or physical tests
  • Pain radiating to the groin, hip, or thigh (not extending below the knee)
  • Diagnostic confirmation before radiofrequency ablation (RFA) of the SI joint nerves

SI joint pain is often unilateral, worsened by standing, stair climbing, or turning in bed, and relieved by lying down.

Procedure

1. Preparation

  • The procedure is performed in an outpatient setting under local anesthesia and fluoroscopic (X-ray) or CT guidance.
  • The patient lies face down, and the skin is sterilized.
  • A small amount of local anesthetic is applied to minimize discomfort.

2. Injection Technique

  • Under fluoroscopy, a thin needle is guided into the sacroiliac joint space.
  • A small quantity of contrast dye is injected to confirm accurate placement.
  • Then, a mixture of local anesthetic (for immediate pain relief) and corticosteroid (for long-term anti-inflammatory effect) is administered.
  • The entire procedure typically takes 10–15 minutes.

3. After the Procedure

  • Patients are observed for a short time and can usually walk and go home the same day.
  • Temporary numbness or mild soreness around the injection site is normal and resolves within hours.

Expected Benefits

  • Pain relief: Many patients experience significant reduction in back and pelvic pain within days.
  • Improved mobility: Allows better participation in physiotherapy and daily activities.
  • Diagnostic clarity: If pain subsides after the injection, the sacroiliac joint is confirmed as the primary pain source.
  • Adjunct therapy: May help postpone or avoid surgery when combined with exercise and posture correction.

Relief may last from several weeks to several months, depending on the degree of joint inflammation and patient response.

Risks & Complications

Sacroiliac joint injections are very safe when performed by trained specialists under image guidance. Potential risks include:

  • Mild injection site pain or bruising
  • Temporary numbness or leg weakness due to anesthetic spread
  • Allergic reaction to medication or contrast
  • Very rare: infection or bleeding near the joint

Severe or long-term complications are extremely uncommon.

Recovery & Follow-Up

  • Rest for 12–24 hours after the procedure is recommended.
  • Most patients resume daily activities the next day.
  • Pain relief may begin immediately or gradually as the steroid reduces inflammation.
  • Follow-up evaluation determines whether additional injections or radiofrequency ablation (RFA) of the sacral nerves is indicated for longer-lasting relief.
  • Regular core strengthening and pelvic stabilization exercises enhance long-term results.

Complementary Therapies

For patients with recurrent SI joint pain, additional options may include:

  • Radiofrequency ablation (RFA): Destroys small pain-carrying nerves for 6–12 months of relief.
  • Prolotherapy or platelet-rich plasma (PRP) injection: In selected chronic instability cases.
  • Sacroiliac joint fusion: A surgical option reserved for severe, treatment-resistant pain.

Patient Advisory

Each patient’s condition is unique — the cause and pattern of pain must be carefully evaluated before treatment. Your neurosurgeon or pain specialist will determine whether a sacroiliac joint block is the most appropriate therapy or part of a broader pain management plan. Do not make medical decisions or interpret results based solely on online information.