Headache in Patients with Cervical Spondylotic Myelopathy

PURPOSE: The anatomical mechanisms of cervicogenic headache caused by upper cervical lesions have been reported. However, the pathomechanisms of headache caused by lower cervical spine disorders remain unknown. The purpose of the current study was to clarify the prevalence and pathogenesis of headaches in patients with cervical spondylotic myelopathy (CSM). METHODS: In this retrospective study, a questionnaire regarding preoperative and postoperative symptoms was sent to 147 patients with CSM who were surgically treated in our hospital during the previous 10 years. All of the surgical procedures were decompression surgeries between the C3 and C7 levels. Data from 74 patients (50.3%) were available for analysis. Subjects were divided into four groups according to the presence or absence of preoperative and postoperative headache. The severity of pain, severity of neuropathic pain symptoms, depression, severity of myelopathy, and quality of life (QOL) were also evaluated using questionnaires. The scores of these questionnaires were then compared between the four groups. Kruskal–Wallis tests with Dunn–Bonferroni post hoc tests were used for comparisons. RESULTS: Of the patients with CSM, 31% had headaches preoperatively, and 43% of these headaches disappeared postoperatively. Type 4 (preoperative headache-positive/postoperative headache-positive) patients had more severe pain and neuropathic pain symptoms and lower QOL scores compared with type 1 (preoperative headache-negative/postoperative headache-negative) patients. CONCLUSIONS: Approximately one-third of all patients with CSM had headaches preoperatively. Headache in patients with CSM may be neuropathic pain. A proportion of headaches in patients with CSM can be treated by decompression surgery.