1Introduction

Most Commonly Used CAM Therapies for Back Pain

Acupuncture is one of the oldest forms of therapy and has its roots in ancient Chinese philosophy. According to the classic acupuncture theory all disorders are reflected at specific points, either on the skin surface or just below it. An appropriate choice of the 361 classic acupuncture points is believed to restore the balance in the body. Modern acupuncturists use not only traditional meridian acupuncture points, but also nonmeridian or extra-meridian acupuncture points. Many acupuncturists (particularly those with conventional medical training) practice without reference to traditional Chinese concepts. The exact mechanisms underlying the action of acupuncture remain unclear. It has been suggested that acupuncture might act by principles of the gate control theory of pain. Another theory relates to diffuse noxious inhibitory control (DNIC), which implies that noxious stimulation of heterotopic body areas modulates the pain sensation originating in areas where a patient feels pain. There is also some evidence that acupuncture may stimulate the production of endorphins, serotonin, and acetylcholine within the central nervous system, enhancing analgesia.³ Acupuncture is a heterogeneous set of diverse practices and therefore some types of acupuncture maybe more effective than others.

Spinal manipulation therapy is defined as the application of high-velocity, low-amplitude manual thrusts to the spinal joints. The practice of spinal manipulation is frequently performed by chiropractors,⁴ and also by osteopaths, and physical therapists. The mechanism of effect of spinal manipulation is unclear; it is hypothesized that spinal manipulation displaces and deforms the tissues, altering orientation or position of anatomic structures, unbuckling some structures, releasing entrapped structures or disrupting adhesions. Other hypotheses focus on the neurological response of cell or matrix systems to the input forces of spinal manipulation. Evidence suggests that spinal manipulation impacts primary afferent neurons from paraspinal tissues, the motor control system, and pain processing.⁵

Spinal mobilization is another commonly used manual therapy that uses low grade/velocity , small or large amplitude passive movement and neuromuscular techniques within a patient’s range of motion. The mechanism of action of spinal mobilization is also not entirely clear. It has been proposed that these spinal techniques improve signs and symptoms by directly facilitating the restricted mobility of the facet joints and simultaneously influencing the mobility of the intervertebral joint.⁶ Spinal mobilization is frequently performed by chiropractors,⁴ and also by osteopaths, and physical therapists.

Massage is a way of easing pain, while at the same time aiding relaxation and promoting a feeling of well-being and a sense of receiving good care by manipulation of local or remote soft tissue. The mechanisms by which massage exerts these multiple therapeutic effects are not yet known. It was hypothesized⁷ that massaging affected muscles and fascia induces local biochemical changes that modulate local blood flow and oxygenation in muscle. These local effects may influence neural activity at the spinal cord segmental level and could modulate the activities of subcortical nuclei that influence mood and pain perception. Soft tissue massage may increase the pain threshold through the release of endorphins. Mechanistic studies are needed to delineate underlying biologic and psychological effects of massage and their relationship to outcomes.³ It is important to note that manual therapies (massage and manipulation / mobilization) are practiced in different ways by different practitioners (e.g. chiropractic manipulation may be quite distinct from that practiced by a physical therapist).

Additionally, nonspecific effects of therapy (i.e. attention/touch/empathy) need to be also considered. For example, it is difficult to separate out specific effects from nonspecific effects of CAM treatment due to the inability to blind subjects to the treatment.

Back Pain and Treatment Approaches

The classification of back pain is not consistent within the clinical community. Generally, back pain treatments are aimed at specific anatomical regions (cervical, thoracic, and lumbar); there is variation in how the various CAM techniques actually affect the intended region currently being treated or other parts of the back. In addition to the body region, clinicians tend to define and develop treatment approaches for back pain based on the perceived underlying mechanical or pathological diagnosis; patients are generally categorized into specific back or nonspecific back pain groups. Specific back pain can include such patient diagnoses as radiculopathopathy, degenerative disc disease, disc herniation, spinal stenosis, or myofascial pain syndrome to name a few. Nonspecific back pain represents the largest clinical groups in which patients are categorized and generally reflects that no particular functional or structural factor is ascribed as the primary source of the current episode. Within both these categories of back pain, there is inconsistency in the manner in which patients are assigned to one or the other category. This problem is further compounded when considering that back pain is recurrent in nature; therefore, many patients with acute back pain may in fact have chronic back pain but are currently being treated for an acute exacerbation. All these factors are potentially key sources of heterogeneity across studies.

Given the inconsistency of grouping persons with symptomatic back pain, it is not surprising that there is significant variation in the treatment approaches used. Variation is further increased by the differing health professionals as well as differing philosophies of treatment within a specific health discipline. Finally, clinicians frequently employ mixed modalities when treating patients with back pain that can be within a specific CAM therapy (for example manipulation and mobilization) or across different types of CAM therapies (for example combining mobilization with acupuncture and exercise). Our primary focus in this systematic review is on evaluating the efficacy of the most prevalent CAM therapies, massage, manual therapy, and acupuncture; and as such, we limited combined treatments to those which would allow evaluation of each of these primary CAM therapies.