Massage Effects, Indications, Contraindications, and Research

Physiologic effects of massage

Massage produces some mechanical effects on the body. Mechanical pressure on soft tissue displaces fluids. Fluid moves in the direction of lower resistance under the static forces of the practitioner's hands, but a moving locus of pressure creates a pressure gradient. Assuming no significant resistance, pressure is lower proximal to the practitioner's advancing hand. Once mobilized fluid leaves the soft tissues, it enters the venous or lymphatic low-pressure systems. The amount of fluid mobilized in any single treatment is likely to be quite small; however, the physiatrist needs to be aware of this physiologic effect in patients with significantly compromised cardiovascular or renal function. When treating lymphedema, massage is performed more proximally and then moves distally, based upon the premise that proximal blockage in the lymph channels must be opened first to allow for subsequent distal mobilization of fluid and protein.

Kneading and stroking massage decreases edema; compression converts nonpitting to pitting edema. In addition to strictly mechanical effects, these massage approaches release histamine, causing superficial vasodilation to assist in washing out metabolic waste products. Venous return increases, which subsequently increases stroke volume.

Some evidence suggests that massage increases blood flow contralaterally; however, the mechanism of this postulated action has not been well established. These effects on mobilization of fluids are more important in flaccid or inactivated limbs, because normal compression supplied by skeletal muscle contraction usually is not present in those cases. Studies suggest that massage may decrease blood viscosity and hematocrit and increase circulating fibrinolytic compounds. Preliminary data suggest an explanation for the success of massage in decreasing deep vein thrombosis (DVT). Massage may be contraindicated in the presence of existingthrombosis.

Other blood compounds that show massage-related increases include myoglobin, creatine kinase, lactate dehydrogenase, and glutamic oxaloacetic transaminase. Temporary increases in these substances represent local muscle cell leakage from applied pressure. Lactate decreases in massaged muscles as well. Massage may decrease muscle spasm and increase force of contraction of skeletal muscle. Decreased spasm and increased endurance may result from wash out of metabolic waste products by fluid mobilization and increased blood flow. Decreased muscle soreness probably results from metabolic wash out.

Reflexive changes

Massage can stimulate cutaneous receptors, spindle receptors, and superficial skeletal muscle as well. These structures produce impulses that reach the spinal cord, producing various effects, including moderation of the facilitated segment. Somatovisceral reflex changes to the viscera are possible in this model.

Psychological effects of massage

Massage generally increases feelings of relaxation and well-being in patients. Whether this is from placebo effect or the result of some previously undiscovered reflex is not fully understood. Practitioners often incorporate a variety of psychophysical techniques, such as guided imagery, into massage treatment. A prospective, nonrandomized trial of massage therapy at a major US cancer center sought to examine massage therapy outcome in a large group of patients. Over a 3-year period, 1290 patients were treated with regular ("Swedish"), light touch, or foot massage, based on the request of the patient. The patients filled out symptom cards before and after a 20-minute (average) massage session. Symptom scores were reduced by approximately 50%, with outpatients demonstrating about 10% greater benefit than did inpatients. Anxiety, nausea, depression and pain demonstrated the greatest improvement in symptom score.

Several studies have investigated the role and potential benefits of massage duringpregnancy. A study by Field and colleagues found such a benefit not only in the recipient of the massage, but also in the patient's spouse.^[2] In this study, self-reported leg pain, back pain, depression, anxiety, and anger were reduced to a greater extent in pregnant women who underwent massage than in women in the control group. In addition, the women's partners, who performed the massages, reported feeling less depression, anxiety, and anger over the course of the massage therapy period than did partners in the control group. Moreover, the pregnant women and their partners showed improved scores on a relationship questionnaire. The data support the positive psychological effects of massage and reinforce thetherapeuticconceptoftouch,aspreviously discussed.

Therapeutic goals and indications for massage therapy

Massage may be used as primary therapeutic intervention or as an adjunct to other therapeutic techniques. Uses can include, but are not limited to, (1) mobilization of intertissue fluids, (2) reduction or modification of edema, (3) increase of local blood flow, (4) decrease of muscle soreness and stiffness, (5) moderation of pain, (6) facilitation of relaxation, and (7) prevention or elimination of adhesions. Massage may be used to alter pathophysiology of a primary condition (eg, contracture) or to prevent or modify deleterious effects of a previously used treatment modality.^[3]

Many studies have focused on the utility of massage to treat low back pain. The authors of one literature review concluded that strong evidence exists for the efficacy of massage in relieving chronic, nonspecific low back pain; they also found "moderate evidence that massage provides short- and longer-term follow-up relief of symptoms." Moreover, the authors determined there to be "moderate evidence that acupressure may be better than Swedish massage" for chronic low back pain, "especially if combined with exercise."

Hospitalized patients who receive massage express improvements in mood, body image, self-esteem, and perceived levels of anxiety. This phenomenon is facilitated by reduction in physical symptoms and distress and may be accompanied by decreased tension, anxiety, and pain perception.

Another therapeutic effect derived from massage is muscle relaxation. Massage appears to reduce tone and enhance circulation to the area. Muscle relaxation also may result from increased sensory stimulation caused directly by massage. This increased sensory input to the spinal cord may result in changes in reflex pathways, leading to central modulatory decreases of muscle tone.

Other effects of massage are enkephalin release, endorphin production, promotion or absorption of fibrous tissue, restoration of connective tissue pliability, improvement of lymphatic flow (in some studies, up to 7-9 times), and increased levels of natural killer (NK) cells. Tanabe and Nakayama provided animal data that suggest that mechanical stimuli, such as massage, to adipocytes may inhibit expression of adipogenic transcription factor peroxisome proliferator-activated receptor, which is independent of systemic energy consumption.^[4] They postulate that such stimuli can assist in reducing the body’s fat stores, and may help to decrease obesity.

Contraindications for massage

Massage is contraindicated when it could cause worsening of a particular condition, unwanted tissue destruction, or spread of disease. Malignancy, thrombi, atherosclerotic plaques, and infected tissue could be spread by massage. Absolute contraindications to massage include (1) DVT, because increased blood flow in a limb could cause a thrombus to detach from the vessel wall, creating an embolism; (2) acute infection; (3) bleeding; and (4) a new open wound. Relative contraindications include (1) incompletely healed scar tissue, (2) fragile skin, (3) calcified soft tissue, (4) skin grafts, (5) atrophic skin, (6) inflamed tissue, (7) malignancy, (8) inflammatory muscle disease, and (9) pregnancy. The physiatrist should be aware that massage must be used very carefully in chronic pain patients.

The direct, hands-on nature of massage may potentiate strong psychophysical effects and may cause unintentional reliance on passive treatment modalities. In all patients, it is necessary to establish treatment end points at the beginning of the treatment period and to terminate treatment when those end points have been achieved. A 2003 review by Ernst that examined the safety of massage found that the majority of adverse effects of massage therapy came about as a consequence of performance by lay practitioners or as a result of using "exotic" massage practices, other than Swedish-style massage.^[5] He further concluded that while massage therapy is not entirely risk-free, reports of serious adverse events appear to be rare. It would be beneficial for the physiatrist, or other prescribing physician, to be aware of the training and experience of the massage therapist to which he or she is referring the patient.

Research in massage

While many studies have been conducted on the clinical utility of massage, the quality of these efforts has been somewhat variable. A number of studies have investigated the use of therapeutic massage in conjunction with exercise, acupuncture, or manipulation, particularly in athletic performance, and the reduction of postexercise or delayed-onset muscle soreness. A Cochrane review article from 2006 included 19 trials (1395 participants) and assessed whether massage alone or in combination with other treatments could help reduce neck pain and improve function. The authors concluded that overall, the quality of the studies was poor and the number of participants in most trials was small. Most studies lacked a definition, description, or rationale for massage and/or the massage technique.^{[6, 7]}

Similar conclusions were reported for numerous other studies, with a common consensus being the need for additional studies on the benefits of therapeutic massage. Research studies evaluating massage have had significant variations in sample size and constitution and have suffered from absence of adequate controls, methodologic errors, and other limitations. The long-term efficacy of massage has not been validated.

Future inquiry must establish the long-term efficacy of massage in a more rigorous, scientific fashion. Studies are needed that, using a valid experimental design, allow pretesting and posttesting; these investigations also need to employ appropriate sample sizes and statistical analysis methods, include reliable and valid measurement tools, and provide some degree of standardization of duration and frequency of treatment. It is also argued that some attempt to control for the so-called placebo effect (as well as touch) must be included in future studies. Additional research may examine the effectiveness of massage when it is used in conjunction with 1 or more other treatments, such as manipulation, exercise, or medications.