A spinal manipulation study has found that manual-thrust manipulation provides greater short-term reductions in self-reported disability and pain scores associated with acute and subacute low back pain, compared with mechanical-assisted manipulation and usual medical care. However, any significant differences were short-term, and lasted no longer than three months.
The study suggests that treatment for acute and subacute low back pain “during the past decade have shown a trend toward increased utilisation of mechanical manipulation devices”. As such, the authors felt it necessary to investigate the basis for this trend. The trial was funded by the National Institutes of Health, National Center for Complementary and Alternative Medicine (NIH/NCCAM) (Grant #R00 AT004196).
The randomised controlled trial, published in the journal Spine, enrolled 107 patients with low back pain with a follow-up of six months. The patients were randomised into three groups: manual-thrust manipulation (patients received high-velocity low-amplitude thrust manipulation in the side posture position); mechanical-assisted manipulation (in a prone position using the Activator IV Instrument; Activator Methods International); and usual medical care (over-the-counter analgesic and nonsteroidal anti-inflammatory drugs, consistent with current clinical guidelines for the primary care practice of non-specific low back pain).
All patients had onset of low back pain within the past 12 weeks. Participants in the manipulation groups were treated twice weekly during a four-week period and subjects undergoing usual medical care were seen three times during this period. Outcome measures included the Oswestry Disability Index (ODI) and numeric pain rating. Outcome measure scores were recorded at baseline, four weeks, three months, and six months.
The authors, led by Michael J Schneider, School of Health and Rehabilitation Sciences, University of Pittsburgh, USA, write, “Linear regression showed a statistically significant advantage of manual-thrust manipulation at four weeks compared with mechanical-assisted manipulation (ODI=−8.1, p=0.009; pain rating=−1.4, p=0.002) and usual medical care (ODI=−6.5, p=0.032; pain rating=−1.7, p<0.001). Responder analysis, defined as 30% and 50% reductions in ODI scores revealed a significantly greater proportion of responders at four weeks in the manual-thrust group (76%; 50%) compared with the mechanical-assisted (50%; 16%) and usual medical care groups (48%; 39%). Similar comparative results were found for pain: manual-thrust (94%; 76%); mechanical-assisted (69%; 47%); and usual medical care (56%; 41%).” It is important to note that patients in all three groups showed clinical improvement at four weeks, three months and six months. No statistically significant group differences were found between mechanical-assisted and usual medical treatments or for any comparison at three or six months.
Schneider at al thus conclude that, over the short term (less than three months), manual-thrust manipulation treatment, as opposed to mechanical-assisted or usual medical treatment offers greater reductions in self-reported low back pain disability and pain scores. The authors also point out that the treatment for this condition “is a classic example of preference-sensitive care” and suggest that all available treatment options should be offered to the patient, as “treatment options that align with patient preferences lead to enhanced patient satisfaction.”
Michael Schneider spoke to Spinal News International, and explained the significance of his findings: “There are two key findings from this study. The first is the comparison between manual manipulation and the mechanical instrument manipulation. Many chiropractors use mechanical instruments as a substitute treatment for manual-thrust manipulation, with the belief that they are therapeutically equivalent. The results of this study question that assumption. Significantly more patients in the manual-thrust group achieved moderate (>30%) or substantial (>50%) reductions in self-reported disability and pain at the end of treatment (four weeks).”
Schneider continued, “The second key finding is the comparison between manual-thrust manipulation and medical care. Many physicians believe that low back pain is a self-limiting disorder that will improve regardless of the type of treatment provided. There is some truth to this statement; about 40-50% of the patients in the medical care group showed moderate or substantial improvement at four weeks. However, manual-thrust manipulation group achieved substantially more improvement; 50-90% showed moderate or substantial improvement at four weeks. This suggests that manual-thrust manipulation should be considered a front-line treatment option for patients with acute or sub-acute low back pain.”