Occipital nerve blocks: when and what to inject?
BACKGROUND
Occipital nerve block (ONB) is a promising treatment for headaches. Its indications, selection criteria, and best techniques are not clear, however.


OBJECTIVE
To summarize in narrative format what is known about ONBs and what needs to be learned.


METHODS
MD Consult and Google Scholar were searched using the terms occipital, suboccipital, block, and injection to identify relevant articles that were reviewed. This process was repeated for all additional pertinent articles identified from these articles, and so on, until no additional articles were identified.


RESULTS
A total of 21 articles were identified.


CONCLUSIONS
Occipital nerve block is an effective treatment for cervicogenic headache, cluster headache, and occipital neuralgia. While a double blinded randomized placebo controlled clinical trial is lacking, multiple open label studies reported favorable results for migraine. Two other possible uses of ONB worthy of further study are use as a rescue treatment and as an adjunctive treatment for medication overuse headache. ONB may be effective for tension headache, but only under very specific circumstances. ONB is either ineffective or only effective under as yet unstudied circumstances for hemicrania continua and chronic paroxysmal hemicrania. Some practitioners use occipital nerve (ON) tenderness to palpation (TTP) or reproduction of headache pain with ON pressure (RHPONP) as selection criteria for identifying appropriate patients. While only a clinical trial can produce a definitive answer, current evidence suggests that these selection criteria are not necessary for cervicogenic headache or cluster headache. Occipital neuralgia by definition involves TTP of the ONs. Whether RHPONP or ON TTP predicts success in migraine is unclear, and may relate to whether steroids are used. A single blinded randomized controlled trial evaluating local anesthetic with steroids vs local anesthetic alone for transformed migraine reported slightly worse results with steroids, but there are several alternate explanations for this finding other than steroids being counterproductive. The technique of repetitive ONBs deserves further study.
Tobin
Joshua
J
21st Century Neurology-Neurology, 2601 North Third Street, Phoenix, AZ 85004, USA.
Flitman
Stephen
S
D000779:Anesthetics, Local / Q000008:administration & dosage*; D000818:Animals; D006261:Headache / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D009407:Nerve Block / Q000379:methods*; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D013127:Spinal Nerves / Q000187:drug effects / Q000502:physiology
D000779:Anesthetics, Local