Greater occipital nerve block for the treatment of migraine: An umbrella review, systematic review, and meta-analysis.

BackgroundGreater occipital nerve block (GONB) has become an established treatment for migraine. Though numerous systematic reviews and randomised control trials (RCTs) are cited as supporting evidence, the quality and consistency of this data remains unclear.MethodsAn umbrella review of systematic reviews investigating GONB for migraine was conducted. Additionally, an independent systematic review and meta-analysis of relevant RCTs was performed in accordance with PRISMA guidelines. Both evaluated MEDLINE ('PubMed'), Embase, and CENTRAL databases.ResultsNine relevant systematic reviews were identified; all had significant limitations and/or contained methodological errors. The reviews had been cited 256 times. None were eligible for statistical analysis.Sixteen RCTs (930 patients) and seven RCTs (401 patients) were included for qualitative and quantitative analyses respectively. Studies were heterogeneous in their methodologies. No serious adverse effects were identified. With moderate certainty, local anaesthetic (LA) GONB reduces headache severity in acute migraine attacks at 30 min (-2.08; p < 0.001). With low certainty, weekly bilateral LA GONB injections reduce headache severity (-1.33; p < 0.001) and monthly headache days (-4.46; p < 0.001) at one month for chronic migraine. Sustained benefits of GONB remain unclear. Data was insufficient to analyse the efficacy of steroid GONB, LA-steroid GONB, nor unilateral GONB for chronic migraine, and GONB - of any type - for episodic migraine.ConclusionsThere is limited RCT evidence supporting GONB for the treatment of migraine. Existing systematic reviews should be interpreted with caution. RCTs with homogeneous methodologies are required to evaluate GONB in the management of disability in migraine.Trial RegistrationPROSPERO registration ID: CRD42024595492.