Acupuncture for pelvic girdle pain of pregnancy (n=386)

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1 Research reviews This section is designed to give a synopsis of some of the latest research published in Medline listed journals over the last year or so. It will concentrate on controlled trials and systematic reviews, but will also include other papers that may be of interest to the readership. Some papers will be reviewed in more detail than others. If summaries and comments are based on an abstract only, this will be indicated. The main reviewer in this section is Mike Cummings, London. Other reviewers are indicated after the relevant review. RCTs Acupuncture for pelvic girdle pain of pregnancy (n=386) Elden H, Ladfors L, Olsen MF, Ostgaard HC, Hagberg H. Effects of acupuncture and stabilising exercises as adjunct to standard treatment in pregnant women with pelvic girdle pain: randomised single blind controlled trial. BMJ 2005;330(7494): The aim of this study was to compare the efficacy of standard treatment, standard treatment plus acupuncture, and standard treatment plus stabilising exercises for pelvic girdle pain during pregnancy. A randomised single blind controlled trial was performed at East Hospital, Gothenburg, and 27 maternity care centres in Sweden. 386 women at between 12 and 31 weeks of pregnancy who met strict diagnostic criteria for pelvic girdle pain were randomised to three treatment groups for six weeks treatment with standard treatment (n=130) consisting of information, advice, pelvic belt and home exercise programme; the same standard treatment plus acupuncture (n=125), or the same standard treatment plus stabilising exercises (n=131). The primary outcome measure was pelvic pain related to motion (visual analogue scale) by morning and evening diary, and the secondary outcome measure was the assessment of severity of pelvic girdle pain by an independent examiner before and after treatment. Morning pain scores showed no reduction in the standard treatment group, reduced from 23 to 15 in the acupuncture group, and reduced from 22 to 18 in the stabilising exercises group. Similar changes were seen in the evening scores. Statistical analysis showed that, after treatment, the stabilising exercise group had less pain than the standard group in the morning (median difference =9, 95% confidence interval 1.7 to 12.8; P=0.0312) and in the evening (13, 2.7 to 17.5; P=0.0245). The acupuncture group, in turn, had less pain in the evening than the stabilising exercise group (-14, to -3.3; P=0.0130). Furthermore, the acupuncture group had less pain than the standard treatment group in the morning (12, 5.9 to 17.3; P<0.001) and in the evening (27, 13.3 to 29.5; P<0.001). Attenuation of pelvic girdle pain as assessed by the independent examiner was greatest in the acupuncture group. In conclusion, acupuncture and stabilising exercises constitute efficient complements to standard treatment for the management of pelvic girdle pain during pregnancy. Acupuncture was superior to stabilising exercises in this study. In many ways this is an exemplary study with much to ponder: pelvic girdle pain of pregnancy was carefully diagnosed with the posterior pelvic pain provocation test, Patrick s test (Faber test), a modified Trendelenburg s test, Lasegue test and palpation of the symphysis pubis. Standard treatment made not the least difference to their pain. The addition of stabilising exercises training the transverses abdominis and multifidi performed in four positions, together with exercises for increasing the circulation in hip rotator muscles, and stretching of the hip external rotators and extensors in the sitting position was significantly superior. Acupuncture had an even greater effect, but this was intensive acupuncture treatment: 17 needles were used, all manipulated to elicit deqi three times in 30 minutes, and treatment was repeated twice weekly for six weeks. Point selection was individualised by tenderness: seven points had to be extrasegmental 86

2 (chosen from GV20, LI4, ST36, BL60) and ten points had to be segmental for symphysis pubis and sacroiliac joints (KI11, ST26, ST32, ST33, GB30, SP12 and Huatuojiaji thoracolumbar fascia at L4/5). There is a growing body of evidence on the value of acupuncture in low back pain in pregnancy, and this study is easily the most rigorous so far, and shows the largest effect. It is difficult to fault it on any technicalities at all, though various statements the authors make lead me to doubt whether the analysis Acupuncture for chronic neck pain (n=135) White P, Lewith G, Prescott P, Conway J. Acupuncture versus placebo for the treatment of chronic mechanical neck pain: a randomized, controlled trial. Ann Intern Med 2004;141(12): Despite substantial increases in acupuncture s popularity and use, its effectiveness for chronic mechanical neck pain remains unproved. The aim of this study was to compare acupuncture and placebo for neck pain. A randomised, single-blind, placebocontrolled, parallel-arm trial with one year follow up was conducted in the outpatient departments of Southampton and Salisbury hospitals, from 1999 to One hundred and thirty five patients of 18 to 80 years of age who had chronic mechanical neck pain were recruited by referral from rheumatologists or primary care physicians or from physiotherapy waiting lists. They had to have a baseline VAS score of 30 (scale 0 to 100) for five of the seven days of the run-in week. Eleven patients withdrew from treatment, and 124 completed the primary end point. Patients were randomly assigned to receive, over four weeks, eight treatments with acupuncture or with mock transcutaneous electrical stimulation to acupuncture points using a decommissioned electroacupuncture stimulation unit. The primary outcome was VAS pain one week after treatment. Secondary outcomes were pain at other time points, score on the Neck Disability Index and the Short Form-36, and use of analgesic medications. Both groups improved statistically from baseline, and acupuncture and placebo had similar credibility. For the primary outcome (weeks 1 to 5), a statistically significant difference in VAS pain in favour of was intention-to-treat in the usual meaning of the phrase. The authors summary statement that acupuncture was the treatment of choice takes no account of the costs of treatment. Finally, these authors admit that they are not sure whether the acupuncture used in this study was optimal. Would the pharmaceutical industry allow trials of suboptimal therapy? I doubt it. Adrian White acupuncture (6.3 mm (95% CI, 1.4 to 11.3 mm); P=0.01) was observed between the two study groups, after adjustment for baseline pain and other covariates. However, this difference was not clinically significant because it demonstrated only a 12% (CI, 3% to 21%) difference between acupuncture and placebo. Secondary outcomes showed a similar pattern. The limitations of the study include the facts that all treatments were provided by one practitioner, so the results are not necessarily generalisable; although the control was credible, it did not mimic the process of needling; and a non-intervention group was not present to control for regression to the mean. The authors concluded that acupuncture reduced neck pain and produced a statistically, but not clinically, significant effect compared with placebo. They also commented that the beneficial effects of acupuncture for pain may be due to both nonspecific and specific effects s The results of this trial are very difficult to interpret, and the authors are cautious in their discussion and conclusions. These were patients with chronic pain (with an average history of about 5 years) needing secondary referral. Both groups of patients were significantly better over time: the improvements in pain in the short term were 66% in the acupuncture group and 48% in the mock TENS group; in the long term the figures were 58% and 55% respectively. By any standards, this is a clinically significant improvement. Acupuncture was responsible for the small difference in the short term effect, but the majority of the benefit was due to other factors. This could have been the interaction with the researcher, the effect of time alone, or the Hawthorne effect simply the result of being involved in a research project. 87

3 It is interesting that this trial did not show effects of acupuncture that have appeared in other trials: some have found that acupuncture is better than control in the first few weeks, but then the difference levels out as the effect of time comes in to play. Other trials have found that there is rather little difference during the time when the acupuncture treatment is being given, but a gap opens up afterwards, during the follow up period. Clearly, the whole business of the effect of acupuncture is complex and there may still be important factors that we are really not aware of. It is not correct to conclude from this study that we should be placing rubber pads on our patients and attaching them to a defunctioned TENS apparatus. That is because the trial treatment also involved telling patients that the machine could stimulate acupuncture points through high frequency, Minimal acupuncture appears as effective as standard acupuncture in migraine (n=302) Linde K, Streng A, Jurgens S, Hoppe A, Brinkhaus B, Witt C et al. Acupuncture for patients with migraine: a randomized controlled trial. JAMA 2005;293(17): Acupuncture is widely used to prevent migraine attacks, but the available evidence of its benefit is scarce. The aim of this study was to investigate the effectiveness of acupuncture compared with sham acupuncture and with no acupuncture in patients with migraine. This was a three-group, randomised, controlled trial (April 2002-January 2003) involving 302 patients (88% women), mean (SD) age of 43 (11) years, with migraine headaches, based on International Headache Society criteria. Patients were treated at 18 outpatient centres in Germany. Acupuncture, sham acupuncture, or waiting list control. Acupuncture and sham acupuncture were administered by specialised physicians and consisted of 12 sessions per patient over eight weeks. Patients completed headache diaries from four weeks before to 12 weeks after randomisation and from week 21 to 24 after randomisation. The main outcome measure was the difference in headache days of moderate or severe intensity between the 4 weeks before and weeks 9 to 12 after randomisation. Between baseline low intensity simulation and therefore would not produce any sensation. This misinformation would not be ethical in a clinical situation. The treatment protocol seems to have been adequate. Treatment was individualised each session according to symptoms and local tenderness, from a list of points derived from previous reports and personal clinical experience. On average six points were used, bilaterally if the pain was bilateral. The main points used were GB20, GB21, GV14, SI12, SI13, SI14, BL9, BL10, LI4, SI3, GB34, TE5. Alternative distal points used were LI11, SI8, TE10, ST36, ST39, ST40, BL60, Luozhen. De qi was elicited from each needle, and during the 20 minutes treatment the needles were manipulated every seven minutes if necessary to continue the sensation. Adrian White and weeks 9 to 12, the mean (SD) number of days with headache of moderate or severe intensity decreased by 2.2 (2.7) days from a baseline of 5.2 (2.5) days in the acupuncture group compared with a decrease to 2.2 (2.7) days from a baseline of 5.0 (2.4) days in the sham acupuncture group, and by 0.8 (2.0) days from a baseline if 5.4 (3.0) days in the waiting list group. No difference was detected between the acupuncture and the sham acupuncture groups (0.0 days, 95% confidence interval, -0.7 to 0.7 days; P=0.96) while there was a difference between the acupuncture group compared with the waiting list group (1.4 days; 95% confidence interval; days; P<0.001). The proportion of responders (reduction in headache days by at least 50%) was 51% in the acupuncture group, 53% in the sham acupuncture group, and 15% in the waiting list group. The authors concluded that acupuncture was no more effective than sham acupuncture in reducing migraine headaches although both interventions were more effective than a waiting list control. This is the first one of the German ART studies (the acronym stands for acupuncture randomised trials) to be published. They are at least two or three others due out shortly. Three were performed with very similar protocols: three arms; superficial needling off-point as the sham control; n=circa300. The results are fascinating, especially when responder rates are 88

4 compared across the three trials, which investigated chronic low back pain, osteoarthrosis of the knee, and migraine (this one). On its own this trial might seem a little disappointing, indeed some commentators have claimed, unsurprisingly, that acupuncture works no better than fake acupuncture or placebo. However, when the results are compared with the other ART studies, the most remarkable outcome is the responder rate in the sham (or minimal) acupuncture group of the migraine trial 53%. In the trial on osteoarthrosis of the knee the responder rate in the sham group was about 27%, Ear acupuncture for postoperative pain (n=61) Usichenko TI, Dinse M, Hermsen M, Witstruck T, Pavlovic D, Lehmann C. Auricular acupuncture for pain relief after total hip arthroplasty - a randomized controlled study. Pain 2005;114(3): Auricular acupuncture (AA) is thought to be effective in the treatment of various pain conditions, but there have been no randomised controlled studies of AA for treatment of acute postoperative pain. The authors tested whether AA of specific points is superior to sham acupuncture for complementary analgesia after total hip arthroplasty in a study in which patients, anaesthetist, evaluator, and analyst were all masked (blinded). The patients were randomly allocated to receive true AA (lung, shenmen, thalamus and hip points) or sham procedure (four non-acupuncture points on the auricular helix). Permanent press AA needles were retained in situ three days after surgery. Postoperative pain was treated with intravenous piritramide (opioid receptor agonist with analgesic potency of 0.7 compared with morphine) using a patient-controlled analgesia (PCA) pump. The time to the first analgesic request, the amount of postoperative piritramide via PCA, and pain intensity on a 100mm visual analogue scale (VAS) were used to evaluate postoperative analgesia. Intraoperative anaesthetic requirement, incidence of analgesiarelated side effects, inflammation parameters and success of patients blinding were also recorded. Fifty-four patients (29 AA and 25 controls) completed the study. Piritramide requirement during the 36 and in the trial on chronic low back pain it was about 36%. The responder rates in the real acupuncture groups were in the region of 50% in all three trials. It could be that the different results in the sham groups indicate more about the studied populations (ie medical conditions) than about the efficacy or otherwise of acupuncture. Thomas Lundeberg (personal communication) suggests that migraine sufferers may have a more dramatic physiological response to superficial needling than normal subjects, in the same way has his research group found for fibromyalgia suffers. hours after surgery in the AA group was lower than in the control: 37+/-18 vs 54+/-21 mg (mean+/-sd); P= Pain intensity on VAS and incidence of analgesia-related side effects were similar in both groups. The differences between the groups as regard patients' opinions concerning success of blinding were not significant. Findings from this study suggest that AA could be used to reduce postoperative analgesic requirement. This is a small well conducted and reported trial. It is similar to the notable work of Kotani et al in The important difference is that instead of using a non-penetrating sham on the same points as the active intervention, as in Kotani et al, the investigators in this trial chose to use off-point needling. The history of acupuncture RCTs is full of needling off-point as a control ( missing the point 2 ), and this method is often criticised; however, if the question the authors were asking was about the point specificity of auricular acupuncture, then the method used is appropriate. Whilst most trials using off-point needling as a control fail to show a difference between groups, occasionally a significant result turns up. In terms of auricular acupuncture, Alimi et al is another example of a positive trial. 3 Similar to the latter trial, Usichenko et al also uses skin resistance measurement to confirm point location. It is possible that, in auricular acupuncture, skin resistance has more relevance than for body acupuncture, since the needle tip stimulates nerves 1 to 2mm under the skin, as opposed to 15 to 40mm or more for body 89

5 acupuncture. A physiological measure made on the skin surface may therefore have more relevance for auricular acupuncture; but this is merely hypothesis. Use of indwelling needles over the perioperative period to reduce postoperative analgesic requirements certainly appears to be a promising technique. Further trials will be needed to independently verify efficacy, before large pragmatic trials can address which technique is most effective in practice. I look forward to see how this field develops. Other papers PET study of acupuncture shows specific effects (n=14) Pariente J, White P, Frackowiak RS, Lewith G. Expectancy and belief modulate the neuronal substrates of pain treated by acupuncture. Neuroimage 2005;25(4): Both specific and non-specific factors may play a role in acupuncture therapy for pain. The authors of this paper explored the cerebral consequences of needling and expectation with real acupuncture, placebo acupuncture and skin-prick, using a singleblind, randomised crossover design with 14 patients suffering from painful osteoarthritis, who were scanned with positron emission tomography (PET). The three interventions, all of which were sub-optimal acupuncture treatment, did not modify the patients pain. The insula ipsilateral to the site of needling was activated to a greater extent during real acupuncture than during the placebo intervention. Real acupuncture and placebo (with the same expectation of effect as real acupuncture) caused greater activation than skin prick (no expectation of a therapeutic effect) in the right dorsolateral prefrontal cortex, anterior cingulate cortex, and midbrain. These results suggest that real acupuncture has a specific physiological effect and that patients expectation and belief regarding a potentially beneficial treatment modulate activity in component areas of the reward system. The key result (for those readers interested in acupuncture rather than expectation) in this study Reference list 1. Kotani N, Hashimoto H, Sato Y, Sessler DI, Yoshioka H, Kitayama M et al. Preoperative intradermal acupuncture reduces postoperative pain, nausea and vomiting, analgesic requirement, and sympathoadrenal responses. Anesthesiology 2001;95(2): Cummings M. ary: Controls for acupuncture - can we finally see the light? BMJ 2001;322(7302): Alimi D, Rubino C, Pichard-Leandri E, Fermand-Brule S, Dubreuil-Lemaire ML, Hill C. Analgesic effect of auricular acupuncture for cancer pain: a randomized, blinded, controlled trial. J Clin Oncol 2003;21(22): appears to be the activation of the ipsilateral insula (part of the limbic system) in patients receiving real acupuncture. This is particularly interesting as most sensory input to the brain is crossed, ie you would expect most activity from a sensory input to register on the opposite (contralateral) side rather than the same (ipsilateral) side of the brain. This may well have been the case of course, since what we see in the results is the difference between scans under the different interventions rather than an unadjusted view. It is difficult to interpret ipsilateral limbic system activation; however, we know that this is an important area of the brain in terms of the affective component of pain, ie how much we suffer with pain. So the paper certainly suggests that real acupuncture does something to the limbic system beyond expectation and beyond skin prick in patients who are in pain. We should note that there are uncrossed fibres travelling from the superficial dorsal horn of the spinal cord (the area where acupuncture probably has its greatest effects in modulating pain) up in the dorsolateral funiculus to the limbic system (Prof Dickinson: personal communication), and the key functions of the limbic system in terms of pain (suffering linked to future avoidance), do not really require lateralisation. You either suffer or you don t, and the side of the body doesn t matter that much in terms of the affective component of pain (ie how it affects you emotionally). By necessity this was a small trial (PET is rather an expensive and time-consuming investigation), but the results appear to have been very important in enhancing the credibility of acupuncture, particularly among sceptical technophiles who follow the general scientific media. 90