Neuromusculoskeletal pain conditions are among the most common complaints for which people consult with a health professional. Acupuncture (and dry needling) is increasingly recognised as a legitimate approach to conservative management of common pain complaints and has a strong public reputation as a safe and effective treatment.
This article presents osteopaths, acupuncturists, and other musculoskeletal health professionals with a research-oriented framework for evaluating the clinical considerations of acupuncture treatment in the management of neuromusculoskeletal pain. It aims to provide information that can inform the application of all approaches to acupuncture practice for pain problems, while recognising that acupuncture practice is diverse and it is difficult to advocate one approach over another.
Pain is increasingly recognized as a major health problem.1 Up to 20% of Australians, including children and adolescents, will suffer chronic pain in their lifetime.2 Epidemiological surveys from other countries indicate similar figures, with some reported prevalence estimates closer to 50%. The high prevalence of persistent pain and disability has a significant economic and human impact on communities.1 According to the recently published Australian National Pain Strategy document, “People suffering chronic pain are at substantially increased risk of depression, anxiety, physical deconditioning, poor self-esteem, social isolation and relationship breakdown. Their reduced physical function and mobility can lead to loss of independence, and they may not be diagnosed and treated for social anxieties that may have contributed to, or result from, their condition.”3
Many people in pain access allied and complementary health professionals. It is estimated that 50-80% of patients who consult a complementary medicine practitioner do so for treatment of pain.3 Acupuncture has a strong reputation as an effective intervention for pain management, and according to Easthope et al.4 “with its high ratings for safety and therapeutic value [acupuncture] is clearly in a different category than other therapies”. There is good evidence that acupuncture as a complement to standard care is cost effective and results in significantly better pain outcomes than standard care alone.5 In Victoria Australia, up to 90% of GPs refer patients for acupuncture.4 Acupuncture is also recommended in the recent UK NICE Guidelines for the early management of persistent non-specific low back pain. It is therefore common for neuromusculoskeletal pain disorders to comprise the majority of complaints for which patients are consulting an acupuncturist.
There is no doubt that a clear role exists for acupuncturists in contributing to efforts to improve patient care for pain conditions. It is also clear from a large body of research that this will be best achieved though an evidence-based and multidisciplinary approach to pain management. This article draws on acupuncture and research literature and presents a synthesis that will aid acupuncture professionals in providing safe and effective care for patients in pain and ensuring efficient interdisciplinary communication.
AN EVIDENCE-BASED APPROACH TO ACUPUNCTURE PAIN MANAGEMENT
The evidence-based medicine (EBM) concept is defined as being (1) the judicious use of the best external evidence, combined with (2) the practitioner’s clinical experience and (3), consultation with the patient. Each of the three parts is important to the overall concept, although in most critiques of EBM, the clinical experience and patient consultation components are mysteriously disregarded.
A common misperception is that practicing according to an EBM model restricts the clinician only to those methods that research has shown to be efficacious, while disregarding previous clinical experience and completely ignoring individual patient needs. Practicing along these lines is clearly in contradiction to the definition of EBM provided above and we refer to this type of misconceived practice as ‘evidence-only medicine’. Practicing EBM is about balancing clinical experience, best external evidence and patient needs. EBM is not the dry, uninvolved application of clinical practice guidelines or management algorithms. Not surprisingly, attempts to practice ‘evidence-only’ medicine are unsatisfactory for both the patient and the practitioner. Attempting to practice ‘evidence-only’ medicine swiftly leads to ‘therapeutic paralysis’, a state where the selection of treatment methods is severely restricted, and the practitioner is unable to offer any treatment for lack of support.
When evaluating the applicability of external evidence to a particular clinical situation, it is important to distinguish between there being the existence of good quality studies that demonstrate no effect of a certain treatment, and there being none, or very few studies that report investigations into the various acupuncture treatment approaches for different conditions. The two situations are completely different, and the onus lies with the presenter of an argument to be clear about which scenario they are referring to. The ‘absence of evidence’ is different from ‘evidence of absence’. Where a relevant evidence base is absent, inconclusive, conflicting, or flawed, emphasis must be placed on the remaining components of EBM – the practitioner’s clinical experience and consultation with the patient.
EVIDENCE OF EFFECTIVENESS FOR NEUROMUSCULOSKELETAL PAIN
The clinical effectiveness of acupuncture has been extensively researched, and numerous systematic reviews and commentaries on these reviews have been published. While there is a remarkable amount of data available, conclusions about the effectiveness of acupuncture unfortunately remain controversial.1 One of the principle difficulties in interpreting data included in systematic reviews is the substantial heterogeneity in both acupuncture treatment variables and the type of controls used. The majority of systematic reviews also report significant biases and methodological inadequacies within primary studies. Therefore, positive conclusions are frequently limited to tentative or qualified support.1-3
In addition to biases that inflate the efficacy of acupuncture, there are other important flaws that lead to false negative conclusions.4,5 Proponents of acupuncture have indicated that many trials do not employ treatment interventions that are considered adequate by most acupuncturists.2,6,7 White et al.6 reviewed 47 systematic reviews of acupuncture published from 2000 to 2007 and reported that only 6 included criteria for assessing treatment adequacy. Further, the adequacy of the sham interventions has also been criticised.8,9 For example, many trials use sham acupuncture procedures that involve active components, and may even be indistinguishable from some forms of real acupuncture.10 Unless both adequate acupuncture and an inactive sham are used in a particular trial, then that trial cannot be interpreted as dismissive.6
Only four systematic reviews of neuromusculoskeletal pain conditions have included criteria for assessing treatment adequacy: two examining low back pain,11,12 and two examining chronic knee pain associated with osteoarthritis.13,14 All four of these trials concluded that acupuncture is significantly more effective than sham interventions. Two other reviews – Ezzo et al.4 examining chronic pain conditions, and Trinh et al.15 examining neck pain disorders – have performed sub-analyses of treatment adequacy components, both reporting that a minimum of 6 sessions was significantly correlated with positive outcomes. Although Ezzo et al. concluded that the evidence of effectiveness over a range of chronic pain conditions is generally limited, the high-quality studies with positive findings included in the review pertained to musculoskeletal pain conditions.4
Ernst et al.1 conducted a series of systematic reviews in 2000 and updated in 2005, which included 7 common neuromusculoskeletal pain conditions. They concluded that the evidence of effectiveness was positive for osteoarthritis and fibromyalgia, tentatively positive for back pain and migraine, and uncertain for headache, neck pain and rheumatoid arthritis. More recent reviews strengthen positive conclusions of effectiveness for osteoarthritis of the hip and knee,13,14,16 and for chronic low back pain.11,17 Acupuncture has been also associated with larger effect sizes than manipulation therapy and exercise for chronic low back pain.18 For neck pain disorders there is moderate evidence of efficacy over placebo and no treatment.15 There is also some evidence to support the efficacy of acupuncture over placebo for lateral elbow pain.19 Evidence remains inconclusive for migraine and tension headache, particularly due to confounding from the use of potentially active sham controls.20,21 There is currently insufficient evidence to either support or refute the effectiveness of acupuncture for shoulder pain.22
A NOTE ABOUT MYOFASCIAL TRIGGER POINT DFRY NEEDLING
Myofascial trigger points (MTPs) are common explanation for regional muscle pain associated with the presence of hyperirritable foci.23 It has been claimed that MTPs are the primary source of musculoskeletal pain in 30-85% of patients.24 Further, MTPs have been identified with nearly every painful musculoskeletal condition, and have even been claimed to mimic other common musculoskeletal conditions.23,25,26,27 The precise pathophysiology of MTPs remains poorly understood, and this is reflected in the impressive range of different methods used to treat them.28 However, the common feature of treatments that have received the majority of attention is the application of direct stimulation at the hyperalgesic foci, including punctate stimulation using an acupuncture needle.29
Many traditional acupuncturists voice growing concern about the proliferation of acupuncture-like ‘dry needling’ of myofascial trigger points by other health professionals in the treatment of musculoskeletal pain. A common criticism is that the programs of training are very short in duration and narrow in scope relative to training in traditional acupuncture and therefore cannot provide adequate instruction or experience to ensure safe and effective treatment. While there is insufficient evidence to determine whether dry needling is more or less safe than acupuncture performed by traditional acupuncturists there are additional issues that acupuncturists should be aware of.
Dry needling of MTPs developed from the observation that long-term therapeutic results of MTP injection therapy (‘wet needling’) were unlikely to be due the injected substance.30,31 In 2001, Cummings and White32 reviewed needling therapies for MTPs and concluded needling appears to be effective but that any positive effect was more reasonably the result of the needle or placebo effects than the injection of a particular substance. Despite the now common belief that direct needle disruption of MTP foci and eliciting a local muscle ‘twitch response’ are essential for confirming adequate treatment and obtaining optimal outcomes,33,34 Baldry has indicated that superficial needling into the subcutaneous tissues directly overlaying MTPs may be equally effective.31,35 Further, a recent meta-analysis of MTP dry needling found no significant evidence that direct dry needling of a MTP is more effective than sham or non-specific needling.24
It should be noted that the validity of MTPs remains controversial. There is currently no accepted diagnostic reference standard, and consensus on the physical diagnostic criteria for MTPs is limited.23 Further, researchers are yet to demonstrate that determination of the presence of a MTP or the commonly proposed clinical features of MTPs are reproducible among different examiners, thereby establishing the reliability of physical examination in the diagnosis of the MTPs.23,35,36 In the absence of an accurate diagnosis, the results of any epidemiological, pathophysiologic, or clinical investigation of MTPs will be misleading.23 The most reliable diagnostic characteristics of MTPs are local tenderness and pain recognition.36 However, the presence of these clinical signs are associated with numerous other musculoskeletal pain conditions, the explanation for which does not necessitate the evocation of a separate pathological entity.36,37 Local tenderness and pain recognition are clinical features also synonymous with the Ashi points described within traditional acupuncture literature.
These issues pose a challenge to claims that direct needling of a clinically relevant pathological entity is responsible for improved outcomes in patients who receive dry needling treatments for trigger points. In fact, needling of tender, symptomatic sites and hypertonic muscles is a common recommendation for pain conditions in most traditional acupuncture systems (i.e. needling Ashi) ,38,39,40 which may indicate that clinical efforts to accurately identify and then penetrate the foci of a MTP are unnecessary.
BALANCING PASSIVE AND ACTIVE MANAGEMENT
There is increasing evidence that over-reliance on passive strategies to pain management is a strong predictor of chronicity and risk of disability.41,42 Active approaches to the management of chronic neuromusculoskeletal pain are frequently associated with better outcomes than passive treatments,43 and where manual therapies have shown benefit it is often when used in conjunction with active management.44-47 According to best practice guidelines, acupuncturists should incorporate active management strategies within the treatment planning for patients with pain complaints.
In the early management of acute musculoskeletal pain, recent practice guidelines have recommended the provision of information (explaining the pain), assurance (that recovery is expected and there is no major problem) and encouragement to gradually resume normal daily activities.48 Advice to continue normal daily activities as soon as possible can reduce the risk of chronic disability development due to pain, and this encouragement should not be dependent on complete pain relief first.49 Waiting for complete pain relief before resuming normal activities appears to be unnecessary and may promote fear-avoidance behaviour which can lead to greater disability.48 If pain persists beyond the acute phase, a programme of graded re-exposure to physical activities according to tolerance, which may include exercises, can be recommended to promote normal movement and maintain strength of the surrounding muscles. However, for acute low back pain the benefit of specific exercises is not strongly supported and patients can be encouraged to resume normal activities directly.48
As pain persists and becomes more chronic, the patient’s presentation is commonly associated with long term reduced or altered movement, and most approaches to pain management should incorporate movement of some kind into the treatment strategy. Stretching exercises and resistance exercises aiming to strengthen deconditioned tissue or to address impairments in control and stability are commonly prescribed for chronic pain and can be effective in some conditions, however, unloaded movement facilitation exercises such as yoga can be equally effective.50 Acupuncturists may feel that prescription of active approaches according to TCM tradition or principles, such as Qi Gong, is more relevant to their practice. A recent, high-quality systematic review of Qi Gong for pain conditions has reported encouraging results.51
Unfortunately, patient adherence to exercises is often poor, and functional reconditioning often requires more than the prescription of a movement programme. Including cognitive-behavioural principles such as setting specific goals and systematic reinforcement of progress within exercise or movement rehabilitation programmes may produce better functional outcomes than exercises alone.52
OPTIMISING ACUPUNCTURE TREAMENT FOR PAIN
The effects of acupuncture within a therapeutic context are complex.1 In addition to the distinct effects of needle penetration at specific locations, every treatment involves a therapeutic relationship, a physical examination, formulation of a diagnosis, and provision of education, advice and often co-interventions.2 Thus the clinical effects of acupuncture may not be easily determined simply by the amount of needling stimulus. The individual patient’s perceptions, for example, of the practitioner’s touch and characteristic needle sensations (de qi), of interoceptive sensations resulting from relaxation, or expectations and other cognitive factors must also be considered.2 Nevertheless, specific acupuncture stimulation is the central feature of acupuncture treatment and therefore the components of needling procedures and the patient’s immediate response to them should be elucidated.2
There is little agreement and very limited research literature regarding the optimal acupuncture needling parameters for the treatment of different conditions and for different patients.2,3,4,5 Extending an international consensus recommendation for optimal acupuncture treatment,5 White et al.2 propose a concept of ‘dose’ of acupuncture, which includes both the stimulus given to the patient and aspects of the patient’s perceptions and response that are known to be linked to subsequent therapeutic responses. While White et al. focus on the neurophysiological correlates of dosage-related factors, the concept of dose should also be seen as important from a traditional acupuncture perspective. Valid conclusions from clinical research will require such a consensus about the factors that are associated with adequate acupuncture treatment for various conditions.
The components of the needling stimulus that are most likely to be significant are: the location of needling; the depth of penetration (tissue level); needle diameter; the intensity and method of manual stimulation, and the presence and nature of the de qi response; the duration of needling; the frequency and intensity of electrical stimulation (where applied); and the treatment schedule.2,3 The patient’s expectations and perceptions resulting from acupuncture needling may prompt modification of these components. The dose may also be affected by the state of the patient (e.g. emotional and physical condition), and different doses may be required for different conditions depending on the intended mechanism of the effect (e.g. Tonifying or Dispersing).2
The choice of needling sites is the most inconsistent parameter within acupuncture therapies, and the one that causes the greatest concern among novices. The numerous acupuncture treatment styles illustrate the considerable variance in the theoretical and clinical processes recommended for choosing effective locations for needling. Clear indications might follow from a universally accepted theory of acupuncture, however, this is not the case and one method cannot be claimed as superior to the rest.6,7,8
Despite the apparent ubiquity of needling sites, it is likely that some sites are more effective than others. From an anatomical perspective, the more commonly used classical acupuncture points have a been associated with muscle motor-endpoints, regions with a high concentration of free nerve endings, and the vicinity of peripheral nerve trunks, which some authors argue may help provide a contemporary rational for the clinical applications of traditional acupuncture literature. Some evidence suggests that acupoints local to the tissue source of the pain (especially those within the same neural segment) have a more significant effect on pain mechanisms. However, there are complex spatial somatic interactions which defy explanation in terms of the traditional segmental organisation of the nervous system. There is no doubt that acupuncture involves a number of significant extrasegmental and cortical effects, or that stimulation of points segmentally distant from pain sites is also effective for relieving pain. Finally, there are obvious anatomical limitations to choosing needling sites that must always be observed.
Very little evidence is available indicating the most effective needling sites for particular conditions. In the absence of high-quality RCTs directly comparing different point selections or point selection methods, evidence may be gleaned from systematic reviews comparing the effects of different treatments across multiple trials.6 For example, Vas and White6 have reviewed acupuncture treatments for osteoarthritis of the knee and report that needling of points distal to the knee may not significantly increase positive outcomes. In a trial examining acupuncture for chronic shoulder pain, the use of local classical shoulder acupoints and distal points on the arm was found to be significantly more effective than superficial needling at ‘sham’ points medial to the Stomach meridian at the tibial crest.9 Tough et al.10 found that there is currently no evidence that direct MTP needling is more effective than needling other sites.
NUMBER OF SITES NEEDLED
There is little evidence on whether a particular number of sites must be stimulated for acupuncture to be effective in pain management.5 The number of sites needled in trials of acupuncture for musculoskeletal pain ranges from 111 to 20.12 Vas and White6 suggest that the correlation between effect sizes and the number of points used across different trials may indicate a threshold effect. For example, in reviewing trials of acupuncture for knee osteoarthritis Vas and White6 report that little benefit may be gained from using more than 4 points. However, this assumes that all possibly effective points for a condition will have an equal effect on outcomes. Such an approach may also fail to allow for the complexities of patient presentations common in clinical practice.
There are also theoretical considerations in choosing the number of sites to be needled. For example, it is commonly believed that regional muscle pain caused by an active MTP can be effectively resolved by deactivation of the MTP using needle penetration.13,14 This suggests that for such presentations needling of a single site should be effective. However, this concept is complicated by the numerous reports that clinical features associated with MTPs usually occur in multiple locations within a symptomatic region.15,16 A traditional acupuncture approach would rarely involve needling only a single symptomatic point. Other local acupoints and distal acupoints along the same meridian may also be used – a procedure which is often mirrored in segmental neurophysiological approaches to acupuncture.7 Carlsson17 has hypothesised that acupuncture needling of multiple local sites may produce cumulative peripheral opioid responses and both manual and electrical acupuncture stimulation at several sites simultaneously has also been associated with cumulative analgesic effects.18,19 The optimal number of sites for maximizing cumulative analgesic acupuncture effects is unknown and may be individual-specific.
The effects of needle depth on clinical outcomes are complex and an optimal depth of needling is currently unknown.5 The substantial heterogeneity of needling variables used in various acupuncture treatments has been used to support the argument that acupuncture works predominantly or entirely as a complex placebo.20 This implies that the specific needle stimulation is not a critical factor in clinical outcomes. However, it has also been suggested that the insertion of needles itself may have a therapeutic effect more or less irrespective of the needling site, depth or stimulation.4,21 For example, several studies report significant pain relief in response to both standard acupuncture and control interventions involving subcutaneous (2-4mm) needling at non-acupuncture sites, but no appreciable difference in outcome between the groups.22-28
There are a number of factors that may determine the depth of needling used. These primarily include: the acupoint being needled, the sensitivity to stimulation, the patient’s condition, the local anatomy, age, body size and body weight. Deeper needling has been shown to be superior to superficial needling in some conditions;5 however, superficial needling can be as effective as deep needling.4,23,29 When needle manipulation is used, the depth of needling significantly increases the volume of tissue stimulated, which may also affect the nature and degree of responses.30
Lund and Lundeberg23 suggest a basis for the hypothesis that stimulation of deep tissues may have a greater effect on the sensory components of pain, whereas superficial needling may have a more predominant effect where there is a larger affective component to a pain complaint. Deeper stimulation may be recommended for many patients as it appears to be more consistently effective in reducing pain and may influence both the sensory and affective dimensions,8,20 however, the patient’s physical condition and sensitivity to acupuncture treatment should be the primary considerations.
Acupuncture needles vary in length, diameter, material, and polishing. The type of needle used is usually based on the intended depth of the tissue to be stimulated and intensity of the stimulation. Polished needles will pass more easily through the skin and may reduce the incidence of needle prick pain. Unpolished needles have a rougher surface and tend to give stronger stimulation during needle manipulation due to increased drag of the surrounding tissue. However, this also results in a greater degree of local tissue trauma. Longer needles used to stimulate deep tissues often require a larger diameter to prevent bending. Marcus30 has demonstrated that the volume of mechanically stimulated tissue increases with the square of the needle radius. Therefore thicker needles will also produce stronger stimulation, as well as increased local tissue damage.
As a general guide, in cases where superficial needling and minimal stimulation is desired a polished needle of 10-30mm length and 0.20-0.25mm diameter may be used. Stronger stimulation and deeper needling may be done with a polished or unpolished needle of 30-75mm length and 0.28-.35mm diameter.
Specific mechanical stimulation in acupuncture occurs as soon as the needle tip (or guide tube) contacts the epidermis. Once the needle enters the tissues continuing mechanical stimulation results from increased local volume due to the presence of the needle. The volume of tissue stimulated may then be further increased by needle manipulation procedures. The magnitude of mechanical effects is related to the radius and depth of the needle, degree of rotary manipulation, and the duration of manipulation.30-33 Langevin et al.33 have demonstrated that common needle manipulation methods involving rotational and longitudinal movements cause connective tissue displacements up to 4cm from the needle shaft.
Needle manipulation is usually performed with the aim of producing or enhancing de qi sensations. Depending on the tradition, stimulation procedures are more or less important in achieving these effects, with some considering them essential for optimal therapeutic effect.8,34 Clinically, the intensity of stimulation used depends significantly on the condition and tolerance level of the patient. Strong responders, sensitive patients, or those with a widespread or multiple-site chronic pain presentation will frequently report adverse reactions during or after mid- to high-intensity stimulation. Other patients may require stronger needle stimulation to achieve significant benefit.
The mechanical and psychophysical effects of needle manipulation are not unique to classical points,32,35,36 however, there is evidence to suggest differences in central neurophysiological responses between classical points and other sites.37,38 Clinically relevant responses to stimulation may not be limited to sensory effects. For example, needle manipulation involving rapid, low-amplitude longitudinal movements, or sparrow pecking in traditional acupuncture, is used in dry needling of MTPs to produce a characteristic local muscle twitch response that is considered essential for optimal outcomes.39
Electrical stimulation of inserted needles is often considered a separate therapy to manual acupuncture and has been termed electroacupuncture (EA). Barlas et al.40 have reported that high-intensity, but not low-intensity, unilateral EA generates a significant and persistent bilateral hypoalgesic effect, indicating that high-intensity stimulation may be important in optimal dose selection for EA. Different analgesic mechanisms have been demonstrated between high- and low-frequency stimulation, with high-frequency at local points recommended for segmental inhibition and low-frequency at distal sites for more diffuse systemic effects.19,33,35,41 Stimulation of local sites may also be an important variable in optimal EA.6,42 Although electrical stimulation is commonly used in trials of acupuncture for pain conditions, the relative effectiveness of electroacupuncture over manual stimulation may vary for different conditions. For example, Vas et al.6 report high-intensity EA stimulation may be important for optimal outcomes in knee osteoarthritis, whereas Furlan et al.60 found EA gave no additional benefit for low back pain. Positive responses to electrical or manual stimulation may also be patient-specific.43
DURATION OF NEEDLING
There are very few comparative studies examining the effect of needling duration on outcomes in musculoskeletal pain.5 Most traditional acupuncture approaches recommend leaving needles in situ for 10-30mins and giving intermittent mechanical stimulation.7,44 A large proportion of acupuncture trials have used comparable strategies. The limited evidence available suggests that less than 5mins is inadequate and greater than 20mins may not confer additional benefits.5,6,45,46 However, short durations, from a few seconds to 2 minutes, can be effective in patients who respond strongly to acupuncture. Shorter needling periods are also recommended for children.
If viewed from a neurophysiological perspective, the duration of retention has little effect on the intensity of the stimulation due to nerve fibre adaptation. However, the duration of needle manipulation may have a significant effect, as an increasing number of nerve fibres are mechanically stimulated.95,99 In some cases, retention of the needle with no stimulation may also limit the therapeutic benefits as the resulting sensations (de qi) are thought to be partly responsible for the specific effects of treatment, however further research is needed to verify this.8,47 Immune responses and other local mechanisms may play an additional role where longer duration of retention without stimulation is used.
There are also theoretical considerations to determining duration. For example, the activation different analgesic mechanisms resulting from mechanical or electrical stimulation may each be dependant on a minimum duration of stimulation.5,48 Li et al.49 have demonstrated broader and more significant characteristic brain responses to needling at a classical point for 3 mins than for 30 or 60 secs. In TCM it is advised that cases of deficiency require longer needle retention duration and less intense stimulation to avoid dispersing qi, whereas stagnation at Ashi points may require only a short duration of retention.
NUMBER AND FREQUENCY OF SESSIONS
There is some evidence that the number and frequency of sessions are an important component of optimal treatment. In a systematic review of acupuncture for chronic pain, Ezzo et al.50 found that six or more treatments was significantly associated with positive outcomes. Trinh et al.51 reported a similar result in a review of acupuncture for neck disorders. Vas et al.6 found that at least 10 sessions was associated with the best outcomes for knee osteoarthritis, with the greatest response occurring in a trial that gave weekly sessions. Ceccherelli et al.3 reported that weekly sessions gave a better results for migraine than bi-weekly sessions. Several weekly sessions may also be more effective for dry needling treatment of MTPs.10 Conversely, Harris et al.52 reported that tri-weekly sessions gave greater symptom relief to fibromyalgia patients than weekly treatment, with the frequency of treatment being the only variable correlated with outcomes.
The relationship between the number of sessions and positive outcomes may be due to various cumulative effects on neurophysiology modulation and endogenous analgesia.17,18,53,54 This might offer further justification to the common convention of recommending patients complete a course of treatment. However, continuing treatment for patients who report little response should be conducted with prudence. In general, where there has been no effect at all from the first 3-4 treatments the diagnosis and treatment strategy should be reviewed. In some cases, it may not be worth persevering.
As is evident from the preceding discussion, there is currently insufficient evidence to draw reliable conclusions from the research literature regarding optimal acupuncture procedures for common musculoskeletal pain disorders. An evidence-based approach will therefore emphasise practitioner clinical experience and consultation with the patient; however, the available data from current evidence as well as consensus criteria from the few systematic reviews of acupuncture for musculoskeletal pain disorders that have used a concept of ‘adequate’ treatment2,6 do offer some clinically useful insights. In addition to treatment considerations related to Pattern and Meridian diagnosis, the following provisional guideline may be proposed:2
- a minimum of six treatments, with a minimum of one treatment per week
- at the least, using several local acupoints
- needles retained for approximately 5-20mins
- where relevant, de qi sensation achieved via initial and intermittent mechanical stimulation, or administration of high-intensity (but sub-noxious) electrostimulation
THE PATIENT’S EXPERIENCE
An optimal dose of acupuncture should also take into consideration each patient’s experience of the treatment proceedure.1 While this is especially important in determining appropriate clinical application and ensuring patient comfort and safety, it is also clear that the significance of communication within the patient-practitioner relationship, incidental factors inherent to the therapeutic encounter, and perceptions relating specifically to the application of acupuncture needling are relevant to the outcome of treatment.
The insertion and manipulation of acupuncture needles is usually associated with characteristic needling sensations, or De Qi.2 The perception of de qi by patients is considered within many acupuncture styles to be necessary for clinical efficacy.3 However, while de qi may reflect relevant therapeutic input, correlation with clinical outcomes is not yet substantiated.4,5 Although data exists supporting a biological model for the role of de qi in acupuncture analgesia and anesthesia in acute pain, data from systematic research on the relationship of de qi to therapeutic effects in the treatment of pain conditions is very limited.5,6
Takeda and Wessel7 have reported that de qi was the sole predictor of positive outcome for knee pain associated with osteoarthritis in both real and sham treatment groups, suggesting that it is an important variable. However, the presence of clinically significant improvements following minimal stimulation superficial needling, such as methods used in Japanese acupuncture styles, may challenge claims that de qi is necessary. A recent study assessing the effects of both the presence and the strength of de qi on clinical outcomes in patients with osteoarthritic pain reported that neither the presence or intensity of de qi had any effect on the pain relief obtained.8 While there is a growing interest in the central neurobiological correlates of de qi and corresponding relationships to brain responses that might be responsible for the therapeutic effects of acupuncture,2,11,12,13 lack of consensus regarding the composite sensations of de qi complicates the interpretation of results.4,6 It is also possible that some components of de qi are more reliable indicators of treatment effectiveness than others.6
Acupuncture needling sensations can be classified as de qi or pain.9 De qi has been associated with sensations of dull aching, heaviness, distension, numbness, tingling, warmth and spreading. 3,4,5,9,10 Sharp, pricking and stinging sensations are usually described as noxious and occur most commonly at the skin.5,10 In addition to the potential for perception of de qi and sharp pain concurrently, the intensity of de qi sensations may reach a threshold after which it is also described as painful.9,11 Further, some components of de qi may be consistently described as painful (e.g. dull aching), although paradoxically not as being noxious.3,9
Gentle needling that induces de qi in the absence of sharp pain has been shown to result in extensive deactivation of limbic and paralimbic brain networks associated with pain processing.4,11,12 In the presence of inadvertent pain this effect is attenuated and a large subset of these regions become activated.4,11 Therefore, in addition to concerns for patient comfort, it is plausible that acupuncture needle stimulation which avoids the production noxious sensations – whether de qi is achieved or not – will be associated with superior clinical outcomes.
There is a growing body of evidence indicating that practitioners can enhance or diminish patients’ pretreatment expectations and that these contextual components of treatment can affect clinical outcomes.14,15,16 In addition to expectations regarding the delivery of health services and general optimism of recovery, patients may also have expectations related to the utilisation of a particular treatment.16,17 This may indicate a need for practitioners to clarify patients’ expectations in relation to acupuncture and related therapies.16
Evidence from some clinical trials has supported a relationship between patient expectations regarding acupuncture treatment and subsequent clinical outcomes. Linde et al.14 performed a pooled analysis of four randomised trials of acupuncture for chronic pain, including 864 patients, and found that expectations regarding the specific acupuncture treatment strategy patients were receiving had a significant impact on outcomes over a period of several months. Kalaoukalani et al.16 evaluated the association between a patient’s expectation of benefit from massage or acupuncture for low back pain and found that regardless of the treatment received, the outcome depended on the magnitude of relative expectations. In contrast, general optimism about treatment, divorced from a specific treatment, was not strongly associated with outcome.
However, a follow up study18 examining the role that treatment preference and expectations may have played in a recent trial comparing traditional individualised acupuncture, standardised acupuncture, simulated acupuncture using toothpicks and usual care for chronic lower back pain conflicted with the above studies. In fact, inconsistency has been noted in the literature on this topic across several other treatments for back pain, suggesting that the relationship between expectations and outcomes may be more complex than is currently thought. A more sophisticated understanding of these relationships is pressing and may assist acupuncturists in “maximising the potential clinical benefits of promoting reasonable treatment options that patients believe will be most helpful”.18
The clinical encounter between patient and practitioner is the core activity of all systems of health care, and acupuncture patients are known to place a high value on the relationship with their acupuncture practitioner.19 Acupuncture treatment is highly characterised by intimate verbal and physical communication between practitioner and patient.20 The nature and quality of these interactions are known to be associated with non-specific effects that significantly influence treatment outcomes and patient satisfaction.21,22
The practitioner–patient relationship has been extensively researched and significant correlations have been made between patient-centred consultations and positive health outcomes.23 For example, Price et al.19 have demonstrated that patients’ perception of acupuncture practitioner empathy has a direct impact on patient enablement and health outcomes. According to Kaptchuk et al.23 the clinical encounter can be divided into three main components: a patient’s response to observation and assessment, the patient’s response to the administration of a therapeutic ritual, and the patient’s response to the patient-practitioner interaction. In a large prospective study they found that such non-specific effects “can be disentangled into the three components that produce incremental improvement in symptoms in a manner resembling a graded dose escalation of component parts”. Non-specific effects were found to produce statistically and clinically significant improvement and supportive interaction with a practitioner was the most potent component of non-specific effects. Enhancing the significance of contextual components of the therapeutic encounter, such as such as warmth, empathy, duration of interaction, and the communication of positive expectation, may therefore maximise positive outcomes.
CURRENT EVIDENCE ON ADVERSE EVENTS AND PATIENT SAFETY
Acupuncture is generally perceived as a harmless procedure. A substantial body of literature examining adverse events following acupuncture indicates that patients can be reassured of the relative safety of needling when performed by a properly trained practitioner.1-6 Nevertheless, acupuncturists must be aware that a wide range of adverse events, from post-treatment fatigue to death, have been reported.1,7-10
The true incidence of adverse events resulting from acupuncture is difficult to determine. A lack of uniform definition and the likelihood of significant underestimation and underreporting has limited the conclusions of systematic reviews.1,5 In addition, the causation of some events is often difficult to determine beyond doubt.10 The incidence of adverse events may also differ according practitioner experience, body region being needled, and style of needling used. For example, superficial needling common in Japanese style acupuncture procedures generally do not employ needle penetration beyond the subcutis or needle manipulation and are therefore less likely to produce adverse events.1
Several large prospective surveys of practitioners using acupuncture have been conducted, reporting adverse events associated with a total of over 5,000,000 treatments in several countries and in a range of settings.6 Data from the four largest and most recent surveys,3,9,11,12 indicate that the most common minor adverse events are transient fatigue, minor local bleeding and haematoma, aggravation of symptoms, needling pain, and dizziness, all of which may occur in no more than 3-4% of treatments. Other minor adverse events include headache, nausea, sweating, bent/stuck needles, and skin irritation. Minor events occur in a total of 7-15% of treatments. Significant minor events, including forgotten needles, needle allergy, local infection, severe nausea and vomiting, fainting, significant exacerbation of pain or other symptoms, and psychological and emotional reactions, were reported to occur in 0-14 per 10,000 treatments. A systematic review of serious adverse events conducted by White4 reported a worldwide total of 715 incidents. The most common events related to infection were hepatitis B infection and infection of the external ear following auricular needling. The most common traumatic events were pneumothorax, cardiac and blood vessel trauma, and brain stem or spinal cord trauma. Causes of death from acupuncture were more frequently associated traumatic events. Other serious events reported were acute asthma attack, seizure, collapse, and dangerous drowsiness.
Although the data across these surveys is generally consistent, the reliability of practitioner reports is widely recognized to suffer from underreporting and underestimation, suggesting that these data should be regarded with a degree of caution.1,4,11,13 MacPherson et al.11 conducted a survey of patients following 30,196 acupuncture consultations given by practitioners from the same professional body sampled in an earlier large survey of practitioner-reported adverse events.11 The data from patient reports indicated a significant minor adverse event rate of 350 per 10,000, compared with a practitioner-reported rate of 13 per 10,000. However, patient reports of adverse events and nocebo effects may also be unreliable as they are significantly influenced by misattribution and provision of information, such as informed consent documents.11,14
Adverse events may be categorised as avoidable or unavoidable. Unavoidable events include needle prick pain, haematoma, nausea or vomiting, and exacerbation of symptoms. Unavoidable events are rarely serious or life-threatening. Adverse events that are undeniably avoidable include needle traumas such as pneumothorax, patient-to-patient infection, fainting of a patient treated while seated, needling when contraindications are present, and failure to remove a needle.1 Events associated with serious needle trauma may be considered entirely avoidable with the judicious application of extensive anatomical knowledge.10 Matching the needle length to the desired depth of penetration is also recommended. Bacterial infection and transmission of viral infection are avoided via standard clinical hygiene protocols and strict usage of single-use disposable needles. Contraindications to needling include bleeding disorders and anticoagulant drugs, local skin infection or lymphoedema, heart valve disease, immunodeficiency, and electroacupuncture in patients with a demand pacemaker.11 Careful attention to patient history, treatment position and patient comfort, vigilance during needle insertion, and encouraging frequent feedback throughout treatment may help minimise many of the common significant minor events. A systematic approach to maximising the safety of needling therapy has been detailed by White.5
CLINICAL DIAGNOSIS IN A MULTIDISCPLINARY ENVIRONMENT
Regardless of the acupuncture treatment model or tradition preferred by a practitioner, a systematic, pathoanatomical approach to screening the patient who presents with a complaint of pain is advisable. There are two main reasons for this: firstly, by first exploring the pain, the acupuncturist pays attention to rare or potentially serious causes of the patient’s pain or other findings that will require medical referral and/or arrangement for multidisciplinary management; and secondly, framing interview and examination findings in pathoanatomical terms will aid efficient interdisciplinary communication where this is necessary. Taking this approach does not preclude a TCM approach to the patient or identifying and treating the individual Pattern. It simply places safety as the first priority, as well as recognising that many patients, especially patients with chronic pain conditions, often require a multidisciplinary approach to pain management to achieve optimal outcomes.
Sources of Pain
The first stage is to identify all possible tissue sources associated with the pain description communicated by your patient. This serves as an aid to integrating pathoanatomical knowledge about possible structural sources of pain by prompting you to consider all of the structures known to be able to produce pain in a certain region. It is also important to have a working knowledge of those structures that are capable of referring pain to the region. Once you have this understanding, you can begin to formulate a problem solving approach to the patient’s pain.
Biomedical Diagnostic Sieve
The second stage in determining the patient’s source of pain is to take a pathological approach – what things can go wrong with the structures in the region of pain that could explain the patient’s current symptoms? To aid your memory, you can use the neumonic ‘FINNDICAATERS’ which is defined here as:
, Inflammatory / Infection
Arterial / Venous,
Endocrine / Metabolic / Nutritional
, Referred pain
, pSychosocial considerations
TCM diagnostic sieve
Acupuncturists are proficient in TCM differential diagnostic processes. A practitioner’s approach to diagnosis will also depend on the particular diagnostic and treatment tradition being used.
A systematic approach requires (and reinforces) a basic knowledge of common pathologies and their clinical presentation. Once a list of possible diagnoses has been generated it is then necessary to narrow these down into a short list of the most likely diagnoses. Therefore, it is only necessary to ask relevant questions and perform relevant tests for those potential diagnoses.
For example, if the patient complains of knee pain, you will have in your mind all of the structures capable of producing knee pain, or referring pain to the knee. You will also have in your mind the list of possible pathologies that can occur at the knee. Where the presence of red flags is already apparent, immediate medical referral is indicated.
Once you’ve narrowed down the possible diagnoses by asking directed questions, you will then need to determine what physical examinations should be performed. As with all patients, the history may indicate that certain systems examinations be undertaken prior to a musculoskeletal assessment (e.g. neurological or cardio-respiratory etc).
Clinicians must also investigate psychosocial considerations that may be relevant to the presentation. This is a complex topic and is therefore addressed in more detail in the following section of the handbook.
The key text from which some of these concepts are based on the work of Professor John Murtagh (2007). Murtagh, J. General Practice, 4th ed. Sydney: McGraw-Hill; 2007.
ASSESSING PSYCHOSOCIAL FACTORS
In both traditional Chinese medicine and modern medicine psychosocial factors have been hypothesised to contribute causally to disease, including acute and chronic musculoskeletal pain. Psychosocial factors are also considered to be obstacles to recovery. It is clear from the scientific literature that a patient’s tendency to catastrophise may increase their risk of chronicity. Further, catastrophisation, vigilance and distress or anxiety resulting from being in pain interacts in some way with patients’ beliefs and behaviours, as well as their coping strategies, which also interacts with how they engage in their work and social lives. In those patients who do develop chronic pain, this complex mix of variables may have an association with the transition of pain from the acute stage to the chronic stage.1
Pain progression is frequently categorised as a temporal transition from acute (0-6 weeks), to sub-acute (6-12 weeks) to chronic (>12 weeks). However, temporality of pain as the criterion for determining chronicity has been questioned.2,3 Loeser and Melzack3 suggest that it may be the individual’s inability to restore homeostatic mechanisms that signals the transition to chronic pain and this may be only partially time dependent. Tan et al. have hypothesised that the TCM theory describes this same phenomenon. However, instead of referring to the biochemical mediators of homeostatic regulation, TCM mediators are described by the concepts of Qi, Blood and Jing. Presentations involving Qi Xu or Yang Xu of the Kidney or Spleen can indicate challenges to physiological fortitude and balance and are similarly associated with fear, anxiety, mental fixation or depression as well as being commonly characterised by the presence of various musculoskeletal conditions (and other symptoms and signs).
Most patients do not go on to develop chronic pain and disability, so it could be argued that an in-depth assessment of psychosocial factors in all acute pain patients is not warranted. However, it is equally important to try and identify those patients in whom psychosocial factors represent a risk of developing chronic pain and disability, such that these factors can be modified with the intention of preventing chronicity and disability.
The assessment of psychosocial factors in patients presenting with a pain problem is based on the concept, and evidence, that psychological, behavioural, social and environmental variables contribute to the pain experience.4-9 There remains, however, controversy regarding the exact nature and extent of this contribution; and this controversy is not helped by the lack of a convincing and substantial body of evidence regarding exactly which psychosocial factors warrant assessment and are modifiable such that the risk of chronicity they pose is reduced.10 The main reason for evaluating psychosocial factors is in the hope that by addressing these factors, patients might be prevented from developing chronic pain and have a greater chance of recovery. While it is logical to target risk factors in prevention, we must recognize that if the variance explained by the risk factor is small, then the changes achieved by modifying those risk factors will also be small.
Multidisciplinary biopsychosocial interventions, behavioural therapy, and cognitive-behavioural therapy have been evaluated for efficacy in those with sub-acute and chronic pain. While some positive benefits arise from the application of these approaches, the recent systematic reviews discussed above do not provide convincing evidence that these approaches offer better outcomes than those already existing biomedical and rehabilitative approaches. For example, while behavioural therapy for chronic low back pain is better than no therapy, and better than placebo, it is not better than exercise therapy.11,12 Similarly, while intensive multidisciplinary biopsychosocial rehabilitation (with functional restoration) improves function and reduces pain, less intensive outpatient multidisciplinary biopsychosocial rehabilitation did not show improvement in pain, function or vocational outcomes when compared with usual care.12,13
Psychosocial factors may primarily increase the risk of chronic pain and disability and may be potentially remediable with a view to reducing the risk of chronic pain and disability and improving rehabilitation outcomes; however, this approach remains largely conceptual.10 Also, the decision to evaluate psychosocial factors in a patient will be influenced by whether they have acute, sub-acute or chronic pain. In patients with acute pain, it is proposed that the acupuncturist should make initial enquires regarding relevant psychosocial factors, with a view to implementing further and more detailed enquiry if the patient’s symptoms do not improve before they enter the subacute phase. Acupuncturists should informally, yet consistently, make an assessment of psychosocial factors during the medical interview and ensuing conversation and to include reassurance, education, and advice to stay active in acute pain patients.14 The primary reason for this is to make an early identification of relevant psychosocial issues in those patients who are progressing toward sub-acute pain and chronicity. However, it should be noted that of those patients with acute low back pain, only 2-7% develop chronic pain,15 and so it is in these 2-7% of patients who develop sub-acute pain (6-12 weeks duration) that psychosocial factors become increasingly relevant. In those with sub-acute pain, it is important to focus on and make a re-assessment of those psychosocial factors that were considered during the acute stage. This can be achieved verbally during the course of conversation, or could be more formally assessed using a questionnaire (such as the Depression, Anxiety, and Positive Outlook Scale – DAPOS16).
In patients who have already developed chronic pain, it is important to identify the presence of psychosocial factors that may have contributed to their current chronicity and therefore psychosocial issues should be more formally assessed. However, it may be considered that since chronicity has already occurred, assessment for psychosocial issues ceases to be for preventative purposes, and becomes important for the holistic management of an existing condition in order to meet patients’ physical and emotional needs. The most effective management of psychosocial factors in sub-acute and chronic pain is difficult to determine from the evidence. For patients who are not already under multidisciplinary care, musculoskeletal practitioners may consider referral to a psychologist or other specialist healthcare professional.
Below is a suggested outline of the extent to which psychosocial factors should be assessed in patients presenting with pain:
> Address the following concerns: “I hurt”, “I can’t move”, ” I can’t work”, I’m scared
> Make informal enquiries as to:
» Beliefs that pain is harmful or potentially disabling
» Fear-avoidance behaviours (physical, domestic, social, and vocational)
» Tendency to low mood and withdrawal from social interaction
» An expectation that passive treatments will help more than active participation
Sub-Acute & Chronic Pain
> As for acute pain, however added emphasis on each of these points is provided as determined on a case-by-case basis
> Re-assess, if necessary
> Consider using a formal questionnaire, such as the DAPOS.*
* Recognising that such questionnaires provide some type of formal quantification of psychosocial issues, but are still being developed and improved.