The Ability of Injections Versus Needle Insertion to Decrease the Severity and Frequency of Symptoms for Patients With Chronic Headaches: A Critically Appraised Topic
Authors: Casciato Alexandra 
Published: September 2024

Clinical Scenario: Headaches can be categorized as tension-type headaches, migraine, trigeminal autonomic cephalgia, and other primary headache disorders according to the Third International Classification of Headache Disorders. Headaches are one of the most common disorders within the nervous system and have a prevalence of >48% within the general population. Nerve blocks are a type of nerve stimulation that is believed to help reduce the frequency and severity of headaches. The physiological effect of the greater occipital nerve block on headaches is thought to be due to the central nervous system connections of the greater occipital nerve and trigeminal and cervical afferent fibers, which is believed to be the prime origin of migraine headaches. Nerve blocks can contain a variety of drug regimens including steroids, local anesthetics, or a mixture of both. Trigger point injections (TPIs) are an invasive therapy where a needle is guided directly into a trigger point that has been previously identified upon examination. Botulinum toxin A is an alternative treatment modality that can be injected with TPIs. Botulinum toxin A is a potent naturally occurring toxin that causes dose-dependent muscular relaxation by inhibiting the release of acetylcholine at the neuromuscular junction. Summary of Key Findings: (1) Both greater occipital nerve blocks and TPIs have been shown to reduce headache frequency and severity in the short term; however, it appears to be due to the needle injected into the soft tissue structures and not due to the type of solution injected. (2) Ultrasound guidance allows for a more accurate and effective technique than a blind injection as it allows for accurate injection into the targeted muscles, thereby minimizing complications and increasing the chance of success. (3) Once symptoms have been alleviated, clinicians should evaluate the patient’s mechanics in the upper trunk to determine whether there are any mechanical abnormalities leading to the formation of myofascial pain and/or trigger points causing the headache symptoms. If identified and treated appropriately, this can allow for a long-term solution in correcting the cause rather than the symptoms alone. (4) Participants receiving a greater occipital nerve block or TPI, despite the drug regimen or dosage, experienced similar benefits with no statistical significance. In deciding which treatment approach to take, the clinician should speak with the patient to educate them on the available options and allow the patient to be part of the decision-making process to best meet their needs and include a rehabilitation plan with all the treatment approaches. Clinical Question: In patients who experience chronic headaches, was there a greater decrease in headache frequency and severity with a greater occipital nerve block or TPI? Clinical Bottom Line: Needles into the supraclavicular region for headaches lead to decreased severity and frequency of headaches in the short term but will not lead to headache resolution. Strength of Recommendation: B.