Although more specialized forms of massage have been found effective for chronic back pain, this may be the first large trial evaluating relaxation massage for this problem. This study found that a course of relaxation massage, using techniques commonly taught in massage schools and widely used in practice, had effects similar to those of a more specialized technique. Specifically, at weeks 10 and 26, adjusted 95% CI’s did not include mean differences in improvement between massage groups large enough to be considered clinically relevant (i.e. 2-point and 1.5-point differences for the RDQ and bothersomeness measures, respectively [8
]). Relaxation massage was also found more effective than usual care in improving function and decreasing pain.
Beneficial effects of both types of massage were evident immediately after the 10-week treatment period and remained statistically and clinically significant for function at the 26-week follow-up. The one-year benefits of massage were of questionable clinical significance. We found no evidence of differential effectiveness among the therapists. Both relaxation and structural massage had very low rates of adverse effects.
The most recent review evaluating the effect of massage on non-specific back pain identified 13 trials published before May 2008 [5
]. As of February, 2011, two additional trials [17
] were identified in MEDLINE. Only the four [19
] trials conducted in North America evaluated techniques similar to the structural massage treatment in our trial, and all found positive results. None of the previous trials evaluated relaxation massage techniques commonly taught in massage schools and widely practiced in North America.
The mechanisms explaining the beneficial effects of relaxation and structural massage remain unclear. These distinct forms of massage may trigger similar physiological effects (e.g., via local stimulation of tissue and/or through a generalized central nervous system response), or may operate through different mechanisms (e.g., structural massage may foster beneficial changes in the treated soft-tissues, while relaxation massage may operate through the central nervous system). It is also possible that improvements in pain and function are due to “non-specific effects” such as time spent in a relaxing environment, being touched, receiving care from a caring therapist, being given self-care advice, or increased body awareness [19
]. A combination of these explanations is also possible.
This study has several limitations: 1) its restriction to participants with non-specific chronic low back pain in a single health care system serving a mostly White and well-off population, 2) exclusion of specific causes of back pain (e.g., disc herniations) which conceivably could benefit more from structurally focused massage, 3) possible therapist bias favoring structural massage, in which they had received specialized training--however, this seems unlikely since the results did not favor structural massage, 4) participants assigned to usual care (which often involved no additional treatment) may have been disappointed they did not get massage, possibly resulting in less positive outcome reports, 5) slight differences in exercises recommended in the two massage groups, and 6), study massage therapists may be atypical, having practiced at least 5 years and learned structural massage techniques. Uncertainties associated with these limitations make it difficult to determine the true magnitude of the benefits of massage observed in this trial. Major strengths include a large sample size, comparison of two massage techniques, inclusion of a control group, having the same therapists deliver both treatments, high treatment adherence and follow-up rates, and long-term follow-up.
Future research should explore the relative contributions of non-specific context effects and specific treatment effects on patient outcomes, whether different forms of massage produce benefits through the same or through different physiological pathways, whether less experienced therapists would produce similar results, whether fewer treatments could have achieved equivalent outcomes, and whether education and self-care recommendations contribute to the effectiveness of massage.
These results indicate that both relaxation and structural massage are reasonable treatment options for persons with chronic low back pain. Possible advantages of relaxation massage are that it is more readily accessible because it is based on techniques taught in virtually all massage schools and is slightly less expensive than more specialized forms of massage which require additional training.