Dose-Response Chiropractic Care for Cervicogenic Headache
Headache is a common pain-related complaint affecting approximately 16% of the general population; cervicogenic headache (HA), defined as pain that originates in the cervical spine and refers to the head, is thought to affect up to 2.5% of the general population and 33.8% of headache patients in pain clinics.
Researchers investigated the effect of chiropractic treatment on cervicogenic HA, specifically focusing on the dose-response relationship number between of treatments and pain relief.
Twenty randomized patients completed the study between February and October 2002. Participants were assigned to one of three treatment groups for comparison: Group one received a total of three office visits, one visit per week, for chiropractic manipulation; group two received a total of nine office visits, three visits per week, for chiropractic manipulation; and group three received 12 total visits, four per week.
Patient HA and functional disability was measured using follow-up questionnaires and the Modified Von Korff (MVK) Scales of Underwood et al, comprised of six 11-point numerical rating scales. "The MVK Pain Scale, the primary outcome, is the average of 3 numerical rating scales (scaled to 100 points) rating: HA pain today, worst HA pain in last 4 weeks, and average HA pain in the last 4 weeks. The MVK Disability Scale is the average score of 3 numerical rating scales measuring interference with 1) daily activities, 2) social and recreational activities, and 3) the ability to work outside or around the house."
Researchers found a correlation between the number of chiropractic visits and positive outcome: "For HA pain, substantial differences were found between participants receiving 1 treatment per week and those receiving either 3 or 4 treatments per week. At four weeks after randomization, the advantage was 13.8 for 3 visits per week and 18.7 for 4 visits per week. At the 12-week follow-up, the advantage was 19.4 for 3 visits per week and 18.1 for 4 visits per week."
According to the authors, this study further supports a larger clinical trial testing the relationship of HA and chiropractic treatment; the researchers conclude that there are benefits to "9 to 12 [chiropractic] visits over 3 weeks for the treatment of HA/neck pain and disability. A larger number of visits than 12 in 3 weeks may be required for maximum relief and durability of outcomes."
Haas M, Groupp E, Aickin M, et al. Dose response for chiropractic care of chronic cervicogenic headache and associated neck pain: a randomized pilot study. JMPT 2004;27(9):547-553.
