What is an occipital nerve block?

From the Guidelines

Occipital nerve block is a recommended procedure for the abortive treatment of migraine, with a "weak for" recommendation, as it has been shown to improve pain outcomes with minimal risks and benefits, as stated in the 2023 U.S. Department of Veterans Affairs and U.S. Department of Defense clinical practice guideline for the management of headache 1.

Procedure Details

The procedure typically involves injecting a mixture of a local anesthetic and a corticosteroid around the greater and/or lesser occipital nerves.

• The injection site for the greater occipital nerve block is approximately one-third of the distance from the occipital protuberance to the mastoid process, about 2-3cm lateral to the midline.
• After sterilizing the area, 2-5ml of the medication mixture is injected using a 25-27 gauge needle.

Efficacy and Safety

Relief from the procedure can be immediate from the local anesthetic and may last hours to months with the addition of steroids.

• Potential side effects include temporary numbness, dizziness, and rarely infection or bleeding.
• The procedure works by reducing inflammation and interrupting pain signals from the occipital nerves, which are often involved in various headache disorders including occipital neuralgia, cervicogenic headaches, and some migraines.

Clinical Considerations

This minimally invasive procedure can be performed in an outpatient setting and typically takes only a few minutes to complete.

• Clinicians should be aware of the benefits and risks of the procedure, as well as the individual patient's values and preferences, when deciding whether to recommend an occipital nerve block for the treatment of migraine, as noted in the guideline 1.
• Additionally, the guideline suggests that greater occipital nerve blocks may be offered to patients with postdural puncture headache (PDPH) after spinal anesthesia with a narrower-gauge needle, although headache may recur in a substantial proportion of patients, as stated in the consensus practice guidelines on postdural puncture headache from a multisociety, international working group 1.

From the Research

Occipital Nerve Block Efficacy

• The effectiveness of occipital nerve block (ONB) for treating occipital neuralgia and migraines has been studied in several research papers 2, 3, 4, 5, 6.
• A prospective analysis of 44 patients with occipital neuralgia found that 95.45% of patients who underwent ONB showed satisfactory results for at least 6 months, with a significant decrease in headache severity and analgesic medication consumption 2.
• However, a randomized, double-blinded, placebo-controlled study found that ONB with local anesthetic and corticosteroid did not reduce the frequency of moderate to severe migraine days in patients with episodic or chronic migraine compared to placebo 3.

Comparison of Local Anesthetics and Corticosteroids

• A study comparing the efficacy of ONB with lidocaine and bupivacaine found no statistically significant difference in the effectiveness of the two local anesthetics 2.
• Another study found that adding triamcinolone to local anesthetics did not improve the outcome of ONB and trigger point injections for chronic migraine or transformed migraine 5, 6.

Safety and Tolerability

• ONB has been shown to be a safe and well-tolerated treatment, with only 3% of patients reporting adverse reactions in one study 4.
• The majority of patients in another study found the treatment to be well tolerated, with no significant differences in outcome measures between the treatment groups 5, 6.

Acute Pain Relief

• A retrospective observational study found that ONB provided significant and immediate relief for acute migraine pain, with 27% of patients reporting significant relief and 42% experiencing reduced pain scores 4.
• Another study found that ONB resulted in significant and rapid relief of headache, neck pain, photophobia, and phonophobia in patients with chronic migraine 5.