RESEARCH REPORT POSTER DISPLAY

CERVICAL MUSCULOSKELETAL IMPAIRMENTS IN CERVICOGENIC HEADACHE – A META-ANALYSIS. Gadotti I, Armijo-Olivo S, Magee D; University of Alberta, Edmonton, Canada

PURPOSE: The differential diagnosis of cervicogenic headache (CEH) requires the presence of a pattern of symptoms and cervical musculoskeletal signs that distinguish it from other types of headaches. The objective of this meta-analysis was to evaluate the available literature regarding cervical musculoskeletal impairments (CMI) in patients with CEH when compared with control subjects. RELEVANCE: The evaluation of musculoskeletal impairments of the cervical spine can help in the diagnosis of CEH as well in its overall treatment. PARTICIPANTS: Not Applicable METHODS: Studies were searched from 1965 up to and including May 2006 and were obtained through a search of bibliographic databases including Medline-Pubmed, Embase, Cochrane Library and Best Evidence, ISI Web of Sciences, and CINAHL. Key words used were: cervicogenic headache, cervical headache, headache, cephalalgia, cervical vertebrae, neck, neck muscles, neck pain, neck injuries, and physical/musculoskeletal impairment. The outcomes of interest were any musculoskeletal impairment in the cervical spine (i.e. altered range of motion, muscular activity, cervical or head posture, and muscular function). ANALYSIS: Two trained physical therapists analyzed all papers for the inclusion/exclusion selection criteria. The methodological quality of the final selected studies was analyzed with a methodological scale. This scale considered nine important methodological issues. Revman 4.2 Software was used to summarize the effects (standardized mean differences) and odds ratio from the variables for each CMI. RESULTS: The database search resulted in a total of 1769 articles. Of these 1769 articles, 21 were selected as potential studies based on their abstracts. However, only 10 met the relevance criteria. Three articles were of strong methodological quality, 4 moderate, and 3 of weak methodological quality. Seven articles were considered for the meta-analysis. The following standardized mean differences between patients with CEH and a control group were found for craniocervical angle: −0.22; complete cervical rotation: −0.54; cervical flexion-extension: −0.78; cervical range of motion of rotation with cervical flexion: −2.23; flexor strength: −0.56; neck flexors endurance: −1.56; flexor muscle performance: −1.08; proprioception of the neck: −0.07. Odds ratio of having the flexion rotation test positive for patients with CEH were 107.54 and manual segmental examination positive at the level Co-C1: 7.89 when compared with control subjects. CONCLUSIONS: Patients with CEH have altered range of motion in rotation, flexion-extension, cervical rotation with cervical flexion, altered cervical flexor strength, and altered cervical flexor endurance when compared with normal subjects. IMPLICATIONS: Musculoskeletal impairments must be evaluated in patients suffering from CEH in order to guide diagnosis and treatment. The cervical flexion-rotation test and cervical manual segmental motion can assist in the differential diagnosis of CEH and in the identification of movement impairment at the C1/2 segment. However, there is a clear need for well-designed controlled trials with greater sample size using valid and reliable methods to investigate CMI in CEH. KEYWORDS: cervicogenic headache, musculoskeletal impairments, meta-analysis. FUNDING ACKNOWLEDGEMENTS: This study was supported by Alberta Provincial CIHR Strategic Training Program in Bone and Joint Health, Izaak Walton Killan scholarship from the University of Alberta, and Physiotherapy Foundation of Canada. CONTACT: igadotti@ualberta.ca