This article is reprinted with the permission of National College of Chiropractic and JMPT. Our special thanks to the Editor, Dr. Dana Lawrence, D.C. for permission to reproduce this article exclusively at Chiro.Org
Patrick Boline, DC, Northwestern College of Chiropractic
Kassem Kassak, MPH, PhD, American University, Beirut, Lebanon
Gert Bronfort, DC, PhD, Northwestern College of Chiropractic
Craig Nelson, DC, Northwestern College of Chiropractic
A.V. Anderson, DC, MD, Pain Assment & Rehabilitation Center, Edina, MN
Funding was provided by:
the Foundation for Chiropractic Education and Research (FCER)
Background: In the United States headaches are responsible for more than 18 million office visits annually, and are the most common reason for using over-the-counter medications. It is estimated that 156 million work days are lost each year because of headaches, translating to $25 billion in lost productivity. Of the categories of chronic headaches, tension-type headaches are most common.
Headaches are commonly treated by chiropractic doctors with spinal manipulation, and several studies have reported good outcomes. These trials however, suffered from either a lack of a control group or inadequate statistical power. The purpose of this randomized clinical trial was to evaluate the effectiveness of spinal manipulation and a common pharmaceutical treatment (amitriptyline) for chronic tension-type headache.
Methods: One-hundred-fifty patients between the ages of 18 and 70 were randomly assigned to receive either six weeks of chiropractic or pharmaceutical treatment which was preceded by a two week baseline period and included a four week, post-treatment follow up period. Main outcome measures were change in patient-reported daily headache intensity, weekly headache frequency, over-the-counter medication usage, and functional health status using the SF-36 Health Survey.
Results: During the treatment period both groups improved at very similar rates in all primary outcomes. Four weeks following the cessation of treatment patients who received spinal manipulative therapy showed a reduction of 32% in headache intensity, 42% in headache frequency, 30% in over-the-counter medication usage and 16% in functional health status. By comparison, patients that received amitriptyline showed no improvement or a slight worsening from baseline values in the same outcome measures. The group differences at four week post-treatment follow up were considered to be clinically important and statistically significant. There is further need to assess the effectiveness of spinal manipulative therapy beyond four weeks and to compare spinal manipulative therapy to an appropriate placebo such as sham manipulation in future clinical trials.
Conclusion: The results of this study show that spinal manipulative therapy is an effective treatment for tension headaches. Amitriptyline was slightly more effective in reducing pain by the end of the treatment period, but was associated with more side effects. Four weeks after cessation of treatment however, patients who received spinal manipulation experienced a sustained therapeutic benefit in all major outcomes in contrast to the amitriptyline group, who reverted to baseline values. The sustained theraputic benefit associated with spial manipulation seemed to result in a decreased need for over-the-counter medication. There is a need to assess the effectiveness of spinal manipulative therapy beyond four weeks and to compare SMT to an appropriate placebo such as sham manipulation in future clinical trials. (see the Problem with Placebo/Shams Page for other issues associated with sham treatments provided in previous studies.)
Key words: clinical guidelines; low back pain; evidence based medicine; systematic reviews