Effectiveness of Massage Therapy for Chronic, Non-malignant Pain: A Review

Jennie C.I. Tsao

Disclosures

Evid Based Complement Alternat Med. 2007;4(2):165-179. 

In This Article

Discussion

The existing literature provides varying levels of support for the effectiveness of massage therapy for chronic pain. The most abundant and rigorous evidence was found for the effects of massage on non-specific LBP. The Cochrane Collaboration,[3] concluded that massage therapy may be beneficial for patients with subacute and chronic non-specific LBP, especially when combined with exercises and education. Whereas the evidence supporting the application of massage for LBP is fairly robust, there is less support for the use of massage for the other chronic pain conditions reviewed. This review suggests that the level of evidence for massage therapy effects by pain condition is (in order from most to least): LBP, shoulder pain, headache pain, fibromyalgia, mixed chronic pain, neck pain and CTS.

Although shoulder pain has been the subject of only three studies, all of the studies yielded positive outcomes for pain and were methodologically rigorous, with one study including over 100 patients.[25] Moreover, one of these studies was cited by Moyer et al.[30] in their meta-analysis indicating that massage therapy demonstrates significant effects on the long-term assessment of pain. Like shoulder pain, massage for headache pain has only been the subject of three studies but the data are somewhat weaker. The Cochrane Collaboration[15] concluded that there is moderate evidence that spinal manipulation is superior to massage plus placebo laser for pain related to cervicogenic headache, although these conclusions were based on the results of a single trial reported in two studies.[16,17] Two additional studies provided preliminary evidence for the benefits of massage and craniosacral therapy in the treatment of pain related to migraine headaches[18] and tension-type headaches,[20] respectively. However, in the migraine study,[18] massage was combined with relaxation and other self-help techniques, making it difficult to draw conclusions regarding the specific effects of massage.

There is considerably less support for the effectiveness of massage therapy in treating the remaining chronic pain conditions. Of the four studies examining massage therapy for fibromyalgia, only two studies, both by the same research group, revealed therapeutic effects,[33,34] whereas the other two studies found no benefits[36] or improvements that attenuated over time.[35] Thus, there is only modest evidence for the effectiveness of massage for pain related to fibromyalgia. For mixed chronic pain, the three studies to date provide somewhat conflicting findings. Whereas one study found that massage was superior to usual care,[37] two other studies found that by follow-up, massage was no better than relaxation,[38] mindfulness meditation or usual care.[39] Taken together, these studies provide fairly weak support for the application of massage to mixed chronic pain. For neck pain, one trial using conventional massage techniques found that massage was similar to acupuncture by 3-month follow-up. A recent Cochrane review which included a broad array of massage techniques, many of which were considered questionable, reported that no firm conclusions could be drawn regarding the effectiveness of massage for neck pain.[31] Only one published trial has investigated massage therapy effects on CTS; this study found that massage was superior to no treatment. Based on these findings, there is only preliminary evidence to support the effectiveness of massage for both neck pain and CTS.

The precise mechanism of action in massage therapy is not known. It has been proposed that increased parasympathetic activity[41] and a slowed-down physiological state may underpin the behavioral and physiological processes associated with massage. As discussed by Wright and Sluka,[42] massage is thought to induce a variety of positive physiological effects that may contribute to tissue repair, pain modulation, relaxation, and improved mood. For example, these authors point to research showing that massage has beneficial effects on arterial and venous blood flow and edema.[43] In addition, they note that vigorous massage has been shown to increase local blood flow and cardiac stroke volume,[44] as well as improve lymph drainage;[45] massage also appears to have an anticoagulant effect.[46] Finally, Wright and Sluka maintain that massage may activate segmental inhibitory mechanisms to suppress pain and that some techniques may activate descending pain inhibitory systems,[43] as suggested by gate theory (discussed subsequently).

The main theories regarding the analgesic effects of massage include gate theory, the serotonin hypothesis, and the restorative sleep hypothesis.[47] According to gate theory,[48] pressure receptors are longer and more myelinated than pain fibers, and thus pressure signals from massage are transmitted faster, closing the gate to pain signals. The serotonin hypothesis maintains that massage increases levels of serotonin, a neurotransmitter that modulates the pain control system.[49] The restorative sleep hypothesis holds that because substance P, a neurotransmitter associated with pain is released in the absence of deep sleep, the ability of massage to increase restorative sleep reduces substance P and consequent pain.[50] There is little definitive data to support these major theories concerning the mechanisms underlying the analgesic benefits of massage.

The existing literature suggests that massage therapy may be a useful approach for pain relief in a number of chronic, non-malignant pain conditions, particularly musculoskeletal pain complaints (e.g., shoulder pain, low back pain). Massage is typically administered as adjunct therapy to help prepare the patient for exercise or other interventions and is rarely administered as the main treatment.[3] Thus, massage is not usually considered a first line treatment, but rather as a complement to other conventional first line approaches (e.g., physical therapy; medications). It should be noted that the studies reviewed above did not specifically report on findings regarding possible interactions of massage therapy with other CAM or conventional medicine approaches. Nevertheless, the increasing popularity of massage and the fact that it is typically used as an adjunctive approach with other established treatments suggests that massage may be successfully integrated into the treatment of a variety of chronic or recurrent non-malignant pain conditions. The paucity of data on negative side effects pertaining to massage does not necessarily mean that such effects do not exist. Future work should focus on systematically characterizing those patients for whom massage is not indicated.

This review highlights the need for continued rigorous research on the effectiveness of massage therapy for chronic, non-malignant pain conditions. Somewhat surprisingly, this review indicated that very few studies to date have focused on massage for pain related to chronic/recurrent headaches and chronic neck pain. Given that massage promotes relaxation, it would appear to be a particularly appropriate therapy for tension-type headaches as well as migraine related to increased stress. Moreover, at pointed out above, massage therapy may alter the mechanical stress caused by myofascial tissue disorders[21] which have been implicated in tension-type headaches.[23] In light of the contradictory findings noted above, future work may also continue to examine massage therapy effects on pain related to fibromyalgia which involves wide-spread, diffuse pain that is often not responsive to traditional approaches.

Numerous methodological problems were noted in the studies reviewed including small sample sizes, lack of equivalence across treatment and control groups, and inadequate blinding of assessors. However, one of the most notable limitations of the literature as a whole is that very few studies included follow-up assessments. As indicated by Moyer et al.[30] in their meta-analysis, the beneficial effects of massage therapy on pain are predominately evidenced after the end of active treatment. They concluded that such delayed effects on pain were substantial, with patients who were evaluated several days/weeks after treatment cessation exhibiting on average 62% less pain than controls and one study on LBP revealed significant benefits from massage persisting 1 year after the cessation of active treatment.[11] It should be noted however, that the conclusions by Moyer et al.[30] were based on only 5 studies, suggesting that future trials of massage therapy should include follow-up assessments in order to further quantify such delayed effects. Moreover, additional studies may focus on examining the optimal time periods for the scheduling of ‘booster’ sessions to maintain treatment gains. Previous work has suggested that psychological treatment delivered according to a schedule with increasing time intervals between sessions (e.g. 1, 4, 10 intervening days) is more effective over the long-term compared to a uniform schedule (e.g. 5, 5, 5 intervening days) of treatment delivery.[51] Thus, future research may also examine the optimal treatment schedule for delivery of massage therapy with a view to enhancing longer-term analgesic effects.

The main limitation of the current study is its reliance on existing reviews and meta-analyses. Thus, many of the conclusions drawn in this article are based on the findings of other authors. Relatedly, the soundness of the methodological approach of these existing reviews may have been limited (e.g. due to improper exclusion of specific studies) as well as highly variable across reviews. Nevertheless, the reliance on extant reviews was considered necessary in order to synthesize a vast and diverse literature examining a broad array of chronic pain conditions. Another limitation of the present study is that only those pain conditions that were the subject of at least one controlled trial of massage therapy were included. Thus, not all chronic pain problems were examined in this review. It is possible that positive effects for massage therapy on other chronic pain conditions may have been reported in uncontrolled trials and/or case studies.

In sum, this review identified important areas for future research on the effectiveness of massage therapy for chronic, non-malignant pain. Whereas there is fairly robust support for the analgesic effects of massage for non-specific LBP, there is only moderate support for such effects on shoulder pain and headache pain. Extant literature provides only modest, preliminary support for massage in treating fibromyalgia, mixed chronic pain, neck pain and CTS. One of the most important methodological considerations that should be addressed in future trials is the inclusion of follow-up assessments in order to allow further quantification of the longer-term effects of massage therapy on pain. Another key methodological consideration is the inclusion of comparison conditions that control for non-specific effects including physical contact and therapist time and attention. Moyer et al.[30] in their meta-analysis maintained that their positive findings for delayed assessment of pain are consistent with the notion that massage may promote pain reduction by enhancing restorative sleep. However, they note that data on sleep patterns was not included in the studies reviewed and therefore, this possibility remains to be tested. Thus, the careful consideration of potential mechanisms may inform future research, particularly with respect to the inclusion of key outcome variables as well as the examination of possible moderators and mediators of treatment response. Additional rigorous research is needed to establish massage therapy as a safe and effective intervention for the treatment of chronic, non-malignant pain.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....