Cervicogenic Headache Responsive To Galcanezumab In Patients With Comorbid Migraine: A Case Series. Running Head: CH And Migraine Responsive To CGRP Abs

Abstract

Introduction Cervicogenic headache (CH) is a chronic headache that is referred to the head from the cervical spine that typically starts or worsens with neck movement. The pain typically presents posteriorly with anterior radiation. Nociceptive input from structures innervated by the upper three cervical spinal nerves can theoretically exacerbate primary headache disorders like migraine. We present three cases of CH related to C1-C2 joint arthropathy that significantly improved after treatment with calcitonin gene-related peptide (CGRP) antibodies initiated for chronic comorbid migraine. Case Descriptions We describe a case series of 3 patients with co-morbid CH and migraine that were treated with CGRP antibodies. All three patients had significant improvement in their migraines with C1-C2 joint injections and subsequently CGRP antibodies provided a greater than 50% benefit in each patient preventing the need for repeat injections. Conclusions The diagnosis of CH in patients is confirmed when treatment of the cervical spine lesion alleviates pain significantly. While CH itself has not been shown to be associated with elevated serum CGRP as has been demonstrated in migraine, animal models of osteoarthritis have shown reduction of hyperalgesia with galcanezumab. An upregulation in CGRP related to nociceptive input from degenerative changes in the cervical spine could lead to potentiation and sensitization which could potentially respond to systemic administration of CGRP antibodies. As a result, the presence of features suggestive of CH in patients with migraine may be a predictor of a positive response to CGRP antibodies. For patients with comorbid migraine and CH, CGRP antibodies could prevent the need for invasive injection treatments.