Massage therapy has been defined as soft-tissue manipulation by trained therapists for therapeutic purposes (1
). Massage therapy has a long history, being first described in China during the second century B. C. and soon thereafter in India and Egypt (1
). More recently, massage therapy has been administered using mechanical devices in addition to hands-on treatment by therapists. Massage can be applied to single or multiple body parts or to the entire body. There are many different types of massage therapy including Swedish massage, Shiatsu, Rolfing, reflexology and craniosacral therapy. Most of the published trials on massage therapy have utilized Swedish or Swedish-type massage.
Despite the growing popularity of massage, there is inconsistent empirical support for its effectiveness in chronic pain. Although the effects of massage therapy on chronic pain has been the subject of prior reviews (described subsequently), most of these reviews have focused on a single chronic pain condition and the level of supportive evidence appears to vary greatly, depending on the particular pain condition investigated. This review aims to bring together the existing data on the effectiveness of massage therapy for a wide range of chronic, non-malignant pain conditions. (Evidence regarding the effects of massage on acute pain is reviewed under ‘Meta-Analysis—Massage Therapy Effects on Pain. Chronic pain has been defined by the International Association for the Study of Pain (IASP) as continuous or recurrent pain that persists for longer than the normal time of healing, generally about 3 months (2
). It is hoped that by providing an overview of the field, gaps in extant research may be identified in order to inform future clinical trials.
Typically, massage is viewed as adjunctive therapy to help prepare the patient for exercise or other interventions, and is rarely administered as the main treatment (3
). Following the methodology of the Cochrane Collaboration, the focus of this review will be on those studies in which massage for pain relief is delivered alone rather than as part of a treatment package, since it is difficult to draw conclusions regarding the effectiveness of massage when multiple treatments are involved. In addition, the emphasis of this review will be on randomized, controlled trials (RCTs) or quasi-RCTs of massage therapy. As noted above, the main purpose of this article is to provide a broad overview of extant literature on the application of massage to a wide range of chronic pain conditions. Prior reviews have typically focused on a single pain complaint, even though many chronic pain patients present with multiple pain conditions. Thus, the current review summarizes the findings of existing reviews and meta-analyses as well as key individual studies that have appeared since the publication of these comprehensive reviews. Although this approach is limited as it depends heavily on the methodology used in extant reviews and the quality of the methodology likely varied across reviews, it was considered the most feasible approach in order to synthesize the large number of studies examining massage for a broad array of chronic pain conditions.
This review is organized as follows. First, empirical findings of effectiveness are presented according to the type of chronic pain condition examined; each of these sections concludes with a summary statement of the level of evidence for the specific pain condition studied. (A summary table of the overall findings is also presented in .) It should be noted that a review of the findings from the handful of studies on mixed chronic pain problems is also included. Second, the results of a meta-analysis of massage therapy for pain complaints are discussed. This study was unusual in that it examined massage therapy effects across a number of pain complaints. The review concludes with a summary of the findings across the various chronic pain conditions, together with a discussion of putative mechanisms, clinical implications and recommendations for future trials.