BACKGROUND: Complex regional pain syndrome (CRPS) is a chronic pain condition that usually occurs in a limb following trauma or surgery. It is characterised by persisting pain that is disproportionate in magnitude or duration to the typical course of pain after similar injury. There is currently no consensus regarding the optimal management of CRPS, although a broad range of interventions have been described and are commonly used. This is the first update of the original Cochrane review published in Issue 4, 2013.
OBJECTIVES: To summarise the evidence from Cochrane and non-Cochrane systematic reviews of the efficacy, effectiveness, and safety of any intervention used to reduce pain, disability, or both, in adults with CRPS.
METHODS: We identified Cochrane reviews and non-Cochrane reviews through a systematic search of Ovid MEDLINE, Ovid Embase, Cochrane Database of Systematic Reviews, CINAHL, PEDro, LILACS and Epistemonikos from inception to October 2022, with no language restrictions. We included systematic reviews of randomised controlled trials that included adults (≥18 years) diagnosed with CRPS, using any diagnostic criteria. Two overview authors independently assessed eligibility, extracted data, and assessed the quality of the reviews and certainty of the evidence using the AMSTAR 2 and GRADE tools respectively. We extracted data for the primary outcomes pain, disability and adverse events, and the secondary outcomes quality of life, emotional well-being, and participants' ratings of satisfaction or improvement with treatment. MAIN RESULTS: We included six Cochrane and 13 non-Cochrane systematic reviews in the previous version of this overview and five Cochrane and 12 non-Cochrane reviews in the current version. Using the AMSTAR 2 tool, we judged Cochrane reviews to have higher methodological quality than non-Cochrane reviews. The studies in the included reviews were typically small and mostly at high risk of bias or of low methodological quality. We found no high-certainty evidence for any comparison. There was low-certainty evidence that bisphosphonates may reduce pain intensity post-intervention (standardised mean difference (SMD) -2.6, 95% confidence interval (CI) -1.8 to -3.4, P = 0.001; I2 = 81%; 4 trials, n = 181) and moderate-certainty evidence that they are probably associated with increased adverse events of any nature (risk ratio (RR) 2.10, 95% CI 1.27 to 3.47; number needed to treat for an additional harmful outcome (NNTH) 4.6, 95% CI 2.4 to 168.0; 4 trials, n = 181). There was moderate-certainty evidence that lidocaine local anaesthetic sympathetic blockade probably does not reduce pain intensity compared with placebo, and low-certainty evidence that it may not reduce pain intensity compared with ultrasound of the stellate ganglion. No effect size was reported for either comparison. There was low-certainty evidence that topical dimethyl sulfoxide may not reduce pain intensity compared with oral N-acetylcysteine, but no effect size was reported. There was low-certainty evidence that continuous bupivacaine brachial plexus block may reduce pain intensity compared with continuous bupivacaine stellate ganglion block, but no effect size was reported. For a wide range of other commonly used interventions, the certainty in the evidence was very low and provides insufficient evidence to either support or refute their use. Comparisons with low- and very low-certainty evidence should be treated with substantial caution. We did not identify any RCT evidence for routinely used pharmacological interventions for CRPS such as tricyclic antidepressants or opioids.
AUTHORS' CONCLUSIONS: Despite a considerable increase in included evidence compared with the previous version of this overview, we identified no high-certainty evidence for the effectiveness of any therapy for CRPS. Until larger, high-quality trials are undertaken, formulating an evidence-based approach to managing CRPS will remain difficult. Current non-Cochrane systematic reviews of interventions for CRPS are of low methodological quality and should not be relied upon to provide an accurate and comprehensive summary of the evidence.
BACKGROUND: Chronic pain, considered to be pain lasting more than three months, is a common and often difficult to treat condition that can significantly impact upon function and quality of life. Treatment typically includes pharmacological and non-pharmacological approaches. Transcutaneous electrical nerve stimulation (TENS) is an adjunct non-pharmacological treatment commonly recommended by clinicians and often used by people with pain.
OBJECTIVES: To provide an overview of evidence from Cochrane Reviews of the effectiveness of TENS to reduce pain in adults with chronic pain (excluding headache or migraine).To provide an overview of evidence from Cochrane Reviews of the safety of TENS when used to reduce pain in adults with chronic pain (excluding headache or migraine).To identify possible sources of inconsistency in the approaches taken to evaluating the evidence related to TENS for chronic pain (excluding headache or migraine) in the Cochrane Library with a view to recommending strategies to improve consistency in methodology and reporting.To highlight areas of remaining uncertainty regarding the effectiveness of TENS for chronic pain (excluding headache or migraine) with a view to recommending strategies to reduce any uncertainty.
METHODS: Search methodsWe searched the Cochrane Database of Systematic Reviews (CDSR), in the Cochrane Library, across all years up to Issue 11 of 12, 2018.Selection of reviewsTwo authors independently screened the results of the electronic search by title and abstract against inclusion/exclusion criteria. We included all Cochrane Reviews of randomised controlled trials (RCTs) assessing the effectiveness of TENS in people with chronic pain. We included reviews if they investigated the following: TENS versus sham; TENS versus usual care or no treatment/waiting list control; TENS plus active intervention versus active intervention alone; comparisons between different types of TENS; or TENS delivered using different stimulation parameters.Data extraction and analysisTwo authors independently extracted relevant data, assessed review quality using the AMSTAR checklist and applied GRADE judgements where required to individual reviews. Our primary outcomes included pain intensity and nature/incidence of adverse effects; our secondary outcomes included disability, health-related quality of life, analgesic medication use and participant global impression of change.
MAIN RESULTS: We included nine reviews investigating TENS use in people with defined chronic pain or in people with chronic conditions associated with ongoing pain. One review investigating TENS for phantom or stump-associated pain in people following amputation did not have any included studies. We therefore extracted data from eight reviews which represented 51 TENS-related RCTs representing 2895 TENS-comparison participants entered into the studies.The included reviews followed consistent methods and achieved overall high scores on the AMSTAR checklist. The evidence reported within each review was consistently rated as very low quality. Using review authors' assessment of risk of bias, there were significant methodological limitations in included studies; and for all reviews, sample sizes were consistently small (the majority of studies included fewer than 50 participants per group).Six of the eight reviews presented a narrative synthesis of included studies. Two reviews reported a pooled analysis.Primary and secondary outcomes One review reported a beneficial effect of TENS versus sham therapy at reducing pain intensity on a 0 to 10 scale (MD -1.58, 95% CI -2.08 to -1.09, P < 0.001, I² = 29%, P = 0.22, 5 studies, 207 participants). However the quality of the evidence was very low due to significant methodological limitations and imprecision. A second review investigating pain intensity performed a pooled analysis by combining studies that compared TENS to sham with studies that compared TENS to no intervention (SMD -0.85, 95% CI -1.36 to -0.34, P = 0.001, I² = 83%, P < 0.001). This pooled analysis was judged as offering very low quality evidence due to significant methodological limitations, large between-trial heterogeneity and imprecision. We considered the approach of combining sham and no intervention data to be problematic since we would predict these different comparisons may be estimating different true effects. All remaining reviews also reported pain intensity as an outcome measure; however the data were presented in narrative review form only.Due to methodological limitation and lack of useable data, we were unable to offer any meaningful report on the remaining primary outcome regarding nature/incidence of adverse effects, nor for the remaining secondary outcomes: disability, health-related quality of life, analgesic medication use and participant global impression of change for any comparisons.We found the included reviews had a number of inconsistencies when evaluating the evidence from TENS studies. Approaches to assessing risk of bias around the participant, personnel and outcome-assessor blinding were perhaps the most obvious area of difference across included reviews. We also found wide variability in terms of primary and secondary outcome measures, and inclusion/exclusion criteria for studies varied with respect to including studies which assessed immediate effects of single interventions.
AUTHORS' CONCLUSIONS: We found the methodological quality of the reviews was good, but quality of the evidence within them was very low. We were therefore unable to conclude with any confidence that, in people with chronic pain, TENS is harmful, or beneficial for pain control, disability, health-related quality of life, use of pain relieving medicines, or global impression of change. We make recommendations with respect to future TENS study designs which may meaningfully reduce the uncertainty relating to the effectiveness of this treatment in people with chronic pain.
BACKGROUND & AIMS: Musculoskeletal pain, the most common cause of disability globally, is most frequently managed in primary care. People with musculoskeletal pain in different body regions share similar characteristics, prognosis, and may respond to similar treatments. This overview aims to summarise current best evidence on currently available treatment options for the five most common musculoskeletal pain presentations (back, neck, shoulder, knee and multi-site pain) in primary care.
METHODS: A systematic search was conducted. Initial searches identified clinical guidelines, clinical pathways and systematic reviews. Additional searches found recently published trials and those addressing gaps in the evidence base. Data on study populations, interventions, and outcomes of intervention on pain and function were extracted. Quality of systematic reviews was assessed using AMSTAR, and strength of evidence rated using a modified GRADE approach.
RESULTS: Moderate to strong evidence suggests that exercise therapy and psychosocial interventions are effective for relieving pain and improving function for musculoskeletal pain. NSAIDs and opioids reduce pain in the short-term, but the effect size is modest and the potential for adverse effects need careful consideration. Corticosteroid injections were found to be beneficial for short-term pain relief among patients with knee and shoulder pain. However, current evidence remains equivocal on optimal dose, intensity and frequency, or mode of application for most treatment options.
CONCLUSION: This review presents a comprehensive summary and critical assessment of current evidence for the treatment of pain presentations in primary care. The evidence synthesis of interventions for common musculoskeletal pain presentations shows moderate-strong evidence for exercise therapy and psychosocial interventions, with short-term benefits only from pharmacological treatments. Future research into optimal dose and application of the most promising treatments is needed.
BACKGROUND: Complementary and alternative medicine (CAM) therapies may be used as a non-pharmacological approach to chronic pain management. While hundreds of trials about individual CAM modality have been conducted, a comprehensive overview of their results is currently lacking for pain clinicians and researchers.
AIM: This umbrella review synthesized the quality of meta-analytic evidence supporting the efficacy, tolerability and safety of CAM therapies for the management of chronic pain.
MATERIALS & METHODS: MEDLINE, EMBASE, CINAHL, and CENTRAL were searched from October 1991 to November 2016. Reviews of clinical trials (randomized and non-randomized) with meta-analysis investigating the utility of any CAM modality for chronic pain were eligible. Pain relief post-intervention was the main outcome and secondary outcomes included patients' adherence and incidence of adverse effects during CAM protocol.
RESULTS: Twenty-six reviews (207 clinical trials, >12,000 participants) about 18 CAM modalities, falling under natural products, mind and body practices or other complementary health approaches were included. Inhaled cannabis, graded motor imagery, and Compound Kushen injection (a form of Chinese medicine) were found the most efficient (with moderate-to-high effect sizes and low heterogeneity) and tolerable (≥80% of adherence to study protocols) for chronic pain relief. When reported, adverse effects related to these CAM were minor.
CONCLUSION: Although several CAM were found effective for chronic pain relief, it remains unclear when these modalities are a reasonable choice against or in conjunction with mainstream treatments. In that sense, future research with a clear emphasis on concurrent evaluation of CAM overall efficacy and patient adherence/tolerance is needed.
BACKGROUND: This article is the first in a series presenting the strongest published evidence for physical and rehabilitation medicine (PRM) to date coming from the Cochrane Collaboration. The intent of the series is to stimulate ideas for reviews and research in neglected areas of PRM.
AIM: To systematically review the rehabilitation contents of the Cochrane Collaboration on disabilities due to spinal disorders or pain syndromes in adults.
METHODS: The Cochrane Database of Systematic Reviews was searched at the end of June 2013 for articles relevant for PRM about disabilities resulting from spinal disorders or pain syndromes in adults. Retrieved papers were classified according to the PRM approach: active therapies, which require active participation by patients to achieve treatment goals, and passive treatments, which rely on the application of external forces. The quality of the reviews was checked against the AMSTAR checklist.
RESULTS: Reviews on spinal disorders or pain syndromes were found in the Cochrane Back Group (CBG) and in the Pain, Palliative and Supportive Care Group (CPPSCG). Thirty-eight (42.8%) of 89 Cochrane reviews in the CBG and 7 (2.4%) of 293 Cochrane reviews in the CPPSCG were included. All were of high quality (range, 8-11 points out of 11 on the AMSTAR checklist). The contents of the reviews are given in detail.
CONCLUSION: This review presents an overview of the current evidence for PRM in the treatment of disabilities due to spinal disorders or pain syndromes in adults. Within PRM there is ample space for research in the Cochrane Collaboration and for producing original studies (randomized controlled trials [RCTs]).
CLINICAL REHABILITATION IMPACT: To apply evidence-based clinical practice, clinicians must be familiar with the current best evidence.
Acupuncture is commonly used for pain control, but doubts about its effectiveness and safety remain. This review was aimed at critically evaluating systematic reviews of acupuncture as a treatment of pain and at summarizing reports of serious adverse effects published since 2000. Literature searches were carried out in 11 databases without language restrictions. Systematic reviews were considered for the evaluation of effectiveness and case series or case reports for summarizing adverse events. Data were extracted according to predefined criteria. Fifty-seven systematic reviews met the inclusion criteria. Four were of excellent methodological quality. Numerous contradictions and caveats emerged. Unanimously positive conclusions from more than one high-quality systematic review existed only for neck pain. Ninety-five cases of severe adverse effects including 5 fatalities were included. Pneumothorax and infections were the most frequently reported adverse effects. In conclusion, numerous systematic reviews have generated little truly convincing evidence that acupuncture is effective in reducing pain. Serious adverse effects continue to be reported. Numerous reviews have produced little convincing evidence that acupuncture is effective in reducing pain. Serious adverse events, including deaths, continue to be reported.
OBJECTIVE: Several systematic reviews (SRs) have assessed the effectiveness of acupuncture for rheumatic conditions, often with contradictory conclusions. Our aim is to provide a critical evaluation and summary of these data. METHODS: Electronic searches were conducted in 15 databases to locate all SRs on acupuncture for rheumatic conditions published since 2000. Data were extracted by the authors according to pre-defined criteria. RESULTS: We found 30 SRs that met our inclusion criteria. They related to the following rheumatic conditions: FM, low back pain, lateral elbow pain, musculoskeletal pain, orthopaedic diseases, OA, RA, shoulder pain, frozen shoulder, neck disorder, AS and sciatica. Their conclusions were in several instances contradictory. Relatively clear evidence emerged to suggest that acupuncture is effective for OA, low back pain and lateral elbow pain and ineffective for FM and RA. CONCLUSION: Many SRs have recently been done. Only for OA, low back pain and lateral elbow pain is the evidence sufficiently sound to warrant positive recommendations of this therapy in routine care of rheumatic patients.
Systematic reviews of acupuncture have tended to support its use, but few applied rigorous inclusion criteria. We tested the credibility of conclusions of systematic reviews of acupuncture published since 1996 by applying rigorous inclusion criteria. Reinterpretation used randomised and double blind trials with valid outcomes or design, and with information available from at least four trials or from 200 patients. Qualified support for acupuncture was originally reported in 12 out of 35 systematic reviews, and strong support was found in another six. Applying stricter inclusion criteria, however, showed that none of the 35 reviews supported acupuncture, predominantly because there were too few patients in the randomised, double blind studies. Six reviews with more than 200 patients in randomised, double blind studies had good evidence of no benefit. Systematic reviews of acupuncture have overstated effectiveness by including studies likely to be biased. They provide no robust evidence that acupuncture works for any indication.
Complex regional pain syndrome (CRPS) is a chronic pain condition that usually occurs in a limb following trauma or surgery. It is characterised by persisting pain that is disproportionate in magnitude or duration to the typical course of pain after similar injury. There is currently no consensus regarding the optimal management of CRPS, although a broad range of interventions have been described and are commonly used. This is the first update of the original Cochrane review published in Issue 4, 2013.
OBJECTIVES:
To summarise the evidence from Cochrane and non-Cochrane systematic reviews of the efficacy, effectiveness, and safety of any intervention used to reduce pain, disability, or both, in adults with CRPS.
METHODS:
We identified Cochrane reviews and non-Cochrane reviews through a systematic search of Ovid MEDLINE, Ovid Embase, Cochrane Database of Systematic Reviews, CINAHL, PEDro, LILACS and Epistemonikos from inception to October 2022, with no language restrictions. We included systematic reviews of randomised controlled trials that included adults (≥18 years) diagnosed with CRPS, using any diagnostic criteria. Two overview authors independently assessed eligibility, extracted data, and assessed the quality of the reviews and certainty of the evidence using the AMSTAR 2 and GRADE tools respectively. We extracted data for the primary outcomes pain, disability and adverse events, and the secondary outcomes quality of life, emotional well-being, and participants' ratings of satisfaction or improvement with treatment.
MAIN RESULTS:
We included six Cochrane and 13 non-Cochrane systematic reviews in the previous version of this overview and five Cochrane and 12 non-Cochrane reviews in the current version. Using the AMSTAR 2 tool, we judged Cochrane reviews to have higher methodological quality than non-Cochrane reviews. The studies in the included reviews were typically small and mostly at high risk of bias or of low methodological quality. We found no high-certainty evidence for any comparison. There was low-certainty evidence that bisphosphonates may reduce pain intensity post-intervention (standardised mean difference (SMD) -2.6, 95% confidence interval (CI) -1.8 to -3.4, P = 0.001; I2 = 81%; 4 trials, n = 181) and moderate-certainty evidence that they are probably associated with increased adverse events of any nature (risk ratio (RR) 2.10, 95% CI 1.27 to 3.47; number needed to treat for an additional harmful outcome (NNTH) 4.6, 95% CI 2.4 to 168.0; 4 trials, n = 181). There was moderate-certainty evidence that lidocaine local anaesthetic sympathetic blockade probably does not reduce pain intensity compared with placebo, and low-certainty evidence that it may not reduce pain intensity compared with ultrasound of the stellate ganglion. No effect size was reported for either comparison. There was low-certainty evidence that topical dimethyl sulfoxide may not reduce pain intensity compared with oral N-acetylcysteine, but no effect size was reported. There was low-certainty evidence that continuous bupivacaine brachial plexus block may reduce pain intensity compared with continuous bupivacaine stellate ganglion block, but no effect size was reported. For a wide range of other commonly used interventions, the certainty in the evidence was very low and provides insufficient evidence to either support or refute their use. Comparisons with low- and very low-certainty evidence should be treated with substantial caution. We did not identify any RCT evidence for routinely used pharmacological interventions for CRPS such as tricyclic antidepressants or opioids.
AUTHORS' CONCLUSIONS:
Despite a considerable increase in included evidence compared with the previous version of this overview, we identified no high-certainty evidence for the effectiveness of any therapy for CRPS. Until larger, high-quality trials are undertaken, formulating an evidence-based approach to managing CRPS will remain difficult. Current non-Cochrane systematic reviews of interventions for CRPS are of low methodological quality and should not be relied upon to provide an accurate and comprehensive summary of the evidence.
