Inflammatory mechanisms in cervicogenic headache: an integrative view

A Review of the Recent Findings in Minimally Invasive Treatment Options for the Management of Occipital Neuralgia

Occipital neuralgia (ON) is unilateral or bilateral neuralgia in the dermatomal nerve distribution of the greater, lesser or third occipital nerves and is a very common presentation of neuropathic pain. ON, although common and well defined, is still a poorly understood pain syndrome. It often requires invasive treatment for long term and significant pain alleviation; however, the evidence supporting different options is still limited. Several minimally invasive techniques have proven to be efficacious and safe, and the selection depends mostly on response to nerve blocks, patient choice and provider preference. This is a comprehensive review of the latest and seminal literature available about occipital neuralgia and currently available minimally invasive treatment options. It covers the anatomical and physiologic biology at the base of neuralgia, the presentation and diagnostic process. It then reviews the available literature to provide description and comparison of the available methods for alleviation.

Occipital Neuralgia and Cervicogenic Headache: Diagnosis and Management

PURPOSE OF REVIEW

Occipital neuralgia (ON) and cervicogenic headache (CGH) are secondary headache disorders with occipital pain as a key feature. Due to significant phenotypic overlap, differentiating ON and CGH from primary headache disorders such as migraine or tension-type headache, or other secondary headache disorders, can be clinically challenging. This article reviews the anatomy, clinical features, unique diagnostic considerations, and management approaches relating to ON and CGH.

RECENT FINDINGS

Conservative therapeutic approaches are considered first-line. Anesthetic nerve blocks may have a dual role in both supporting diagnosis and providing pain relief. Newer minimally invasive procedures, such as pulsed radiofrequency (PRF) and occipital nerve stimulation (ONS), represent an exciting therapeutic avenue for severe/refractory cases. Surgical interventions should be reserved for select patient populations who have failed all other conservative and minimally invasive options, to be weighed against potential risk. ON and CGH represent an ongoing diagnostic challenge. Further studies are required to consolidate efficacy regarding the comprehensive management of ON and CGH.

Therapeutic options for cervicogenic headache

The term cervicogenic headache (CeH) describes a syndrome originating from the cervical spine. There are a variety of therapeutic approaches used for the management of CeH, but scientific evidence of their effectiveness is scarce. No medication drug has proven to be effective. The evidence for greater occipital nerve blocks, cervical nerve blockades, facet joint injections and surgical procedures is limited. Several physical therapy interventions are proposed for CeH, with spinal manipulation and soft tissue interventions being the most commonly used. However, the lack of solid evidence of positive effects and risks of serious complications for spinal manipulation should be considered in favor of other physical therapy interventions associated with less risk. The inconsistent results in the literature can be related to the fact that maybe not all therapeutic interventions are appropriate for all patients with CeH or maybe not all patients with CeH will benefit from particular interventions.

Cervicogenic headache: practical approaches to therapy

Cervicogenic headache is a relatively common and still controversial form of headache arising from structures in the neck. The estimated prevalence of the disorder varies considerably, ranging from 0.7% to 13.8%. Cervicogenic headache is a 'side-locked' or unilateral fixed headache characterised by a non-throbbing pain that starts in the neck and spreads to the ipsilateral oculo-fronto-temporal area. In patients with this disorder, attacks or chronic fluctuating periods of neck/head pain may be provoked/worsened by sustained neck movements or stimulation of ipsilateral tender points. The pathophysiology of cervicogenic headache probably depends on the effects of various local pain-producing or eliciting factors, such as intervertebral dysfunction, cytokines and nitric oxide. Frequent coexistence of a history of head traumas suggests these also play an important role. A reliable diagnosis of cervicogenic headache can be made based on the criteria established in 1998 by the Cervicogenic Headache International Study Group. Positive response after an appropriate nerve block is an essential diagnostic feature of the disorder. Differential diagnoses of cervicogenic headache include hemicrania continua, chronic paroxysmal hemicrania, occipital neuralgia, migraine and tension headache. Various therapies have been used in the management of cervicogenic headache. These range from lowly invasive, drug-based therapies to highly invasive, surgical-based therapies. This review evaluates use of drug therapy with paracetamol and NSAIDs, infliximab and botulinum toxin type A; manual modalities and transcutaneous electrical nerve stimulation therapy; local injection of anaesthetic or corticosteroids; and invasive surgical therapies for the treatment of cervicogenic headache. A curative therapy for cervicogenic headache will not be developed until increased knowledge of the aetiology and pathophysiology of the condition becomes available. In the meantime, limited evidence suggests that therapy with repeated injections of botulinum toxin type A may be the most safe and efficacious approach. The surgical approach, which includes decompression and radiofrequency lesions of the involved nerve structures, may also provide physicians with further options for refractory cervicogenic headache patients. Unfortunately, the paucity of experimental models for cervicogenic headache and the relative lack of biomolecular markers for the condition mean much is still unclear about cervicogenic headache and the disorder remains inadequately treated.