1 School of Medicine, McMaster University, 2 Department of Medical Sciences and 3 School of Rehabilitation Science, McMaster University, Hamilton, 4 Department of Kinesiology, Redeemer University College and 5 Ancaster Sports Medicine Centre, Ancaster, Ontario, Canada.
Correspondence to: K. Trinh, Office of MD Admissions, McMaster University, 1200 Main Street West, Hamilton, Ontario, Canada L8N 3Z5.
![]() |
Abstract |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Methods. Online bibliographic database searches in any language from Medline, PsychINFO, CINAHL, Healthstar, PMID, CAM, EMBASE, Cochrane Database of Systematic Review (3rd quarter 2003), articles listed in reference lists of key articles and the author's personal files were performed. Randomized and quasi-randomized controlled trials examining the effects of acupuncture on lateral epicondyle pain were selected. From the six studies that met inclusion criteria, the first author, year of publication, population studied, dropout rate, treatment plan, assessment scale and outcome measures were extracted. Study quality was determined by using the Jadad scale, in which all studies were rated as high quality. A best evidence synthesis approach was used to analyse the data presented in the six studies.
Results. All the studies suggested that acupuncture was effective in the short-term relief of lateral epicondyle pain. Five of six studies indicated that acupuncture treatment was more effective compared to a control treatment.
Conclusions. There is strong evidence suggesting that acupuncture is effective in the short-term relief of lateral epicondyle pain.
KEY WORDS: Epicondylitis, Elbow pain, Tennis elbow, Acupuncture, Systematic review, Best evidence synthesis approach
![]() |
Introduction |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
There are several conventional therapies for tennis elbow, including transcutaneous electrical nerve stimulation, braces, conventional physiotherapy (such as stretching and strengthening exercises), corticosteroid injections [3] and surgery [5]. These interventions are believed to relieve pain, promote tissue healing and improve joint mechanics [1]. However, there is conflicting information regarding the effectiveness of these therapies [6]. Three systematic reviews on the conventional therapies for lateral elbow pain have been published in the Cochrane Review Series [5, 7, 8]. All three reviews concluded that there was little evidence supporting the effectiveness of these treatments. For instance, according to Buchbinder et al. [5] the results for surgical intervention were inconclusive due to the lack of randomized controlled trials. A second review by Buchbinder et al. [7] examined the efficacy of shock-wave therapy for lateral elbow pain. No conclusions could be drawn, due to conflicting results. Furthermore, the limited number of trials using orthotic devices in the review by Struijs et al. [8] prevented any definitive conclusions from being made.
Outside of the Cochrane Review Series, three systematic reviews of conventional therapies and corticosteroid injections for lateral epicondyle pain have been published [911]. These reviews also found little evidence on which to base clinically relevant conclusions for the effective treatment of lateral epicondyle pain, due to factors such as methodological weaknesses and heterogeneity. It was therefore difficult to formulate unequivocal clinical conclusions.
In the past 10 yr, acupuncture has gained wider acceptance for treating pain [3, 12]. Recently, in a publication by the National Institutes of Health (NIH), it was determined that results were promising enough to support the use of acupuncture. Areas in which the NIH felt acupuncture might be an acceptable alternative are low back pain, stroke rehabilitation, asthma, addiction and tennis elbow. In the Cochrane Review Series, there was one review examining the effectiveness of acupuncture treatments in lateral elbow pain [13]. The authors, Green et al., concluded that there was insufficient evidence to support the use of acupuncture in achieving long-term results for lateral epicondyle pain. The results did indicate that acupuncture provided short-term relief from such pain; however this finding is based on the results of two small trials, the results of which were not able to be combined in meta-analysis.
From the authors experience in this area, we felt that the Cochrane review by Green et al. on lateral epicondyle pain was heterogeneous, in which case meta-analysis might not be the most appropriate method of synthesizing the evidence. Since the Cochrane review, four new clinical trials meeting inclusion criteria have been identified [4, 14, 15; D. Irnich, H. Karg, N. Behrens, M. A. Schreiber, M. Krauss, P. Kroling, personal communication]. Therefore, we decided to conduct a systematic review of acupuncture and lateral epicondylitis using either a meta-analysis or the best evidence synthesis approach (BESA), depending whether the newly identified trials could be combined quantitatively or qualitatively, respectively. If the studies were clinically homogeneous, the results could be pooled statistically. On the contrary, if the studies were clinically heterogeneous it would be inappropriate to pool the studies statistically. Therefore, a qualitative analysis of the results using BESA would be employed. Furthermore, it has been over 2 yr since Green et al. published their paper, and because more recent studies have been published on this topic we feel that this was the right time to revisit this topic.
![]() |
Methods |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Selection criteria and outcome
Two independent reviewers assessed all the identified articles based on the following inclusion criteria: (i) the article described an original study; (ii) the study included patients with pain resulting from tennis elbow, lateral epicondyle pain, lateral elbow pain, lateral epicondylitis, or any description of pain originating from the common origin of the extensor tendon; (iii) patients were randomly or quasi-randomly assigned to the treatment groups; and (iv) needle acupuncture was used as the primary intervention.
Because of our prior knowledge of the small number of studies on this topic, we decided to include both randomized and quasi-randomized studies. There was no language restriction in the inclusion criteria; translators were contacted if necessary.
Exclusion criteria included (i) patients with elbow problems other than lateral epicondyle pain, such as fractures or neurological conditions, and (ii) patients concurrently receiving other treatments.
Data analysis
Using the ChiSquare program, we calculated the agreement between investigators for the assessment of validity. The kappa statistic was used to measure agreement. Results less than zero reflect poor agreement, 00.20 slight agreement, 0.210.40 fair agreement, 0.410.60 moderate agreement, 0.610.80 substantial agreement and 0.811.00 almost perfect agreement [16].
Using a random effects model, the standard mean difference (SMD) and 95% confidence interval was calculated for outcomes reported in a continuous data format. SMD was used because different measures were frequently used to address the same clinical outcome. For instance, some studies measured pain intensity with a visual analogue scale while others measured pain unpleasantness with a 010 scale. The effect size (SMD) is a unitless measure reported in standard deviation units. Generally, an effect size can be interpreted as small (0.20), medium (0.50) and large (0.80), as defined by Cohen [17]. The SMD needs to be considered carefully as both positive and negative SMD can indicate a positive effect. For example, a negative SMD can reflect a reduced pain level or increased function, while a positive SMD can reflect a decrease in pain intensity or improved disability.
Dichotomous data were extracted for outcomes when continuous data were not available. Using a random effects model, the relative risk and the outcome rate in the treated vs control group was calculated. For undesirable outcomes, such as pain intensity on a VAS, a relative risk less than one represented a beneficial treatment.
Clinical judgement was used regarding the similarity of sample populations, types of elbow pain, interventions, durations of treatment, and outcomes used for assessment. Statistical pooling could be used to combine the treatment effects of studies with similar clinical features. If the studies were too dissimilar in clinical features, no statistical pooling should be used. Statistical method for pooling should also not be used if the test of homogeneity was statistically significant. In these instances, a qualitative review was performed as follows: Level 1, strong evidencegenerally consistent findings in multiple (two or more) high-quality randomized controlled trials; Level 2, moderate evidencegenerally consistent findings in one high-quality randomized control trial and one or more low-quality randomized controlled trials; Level 3, limited evidencegenerally consistent findings in one high-quality randomized controlled trial or more than one low-quality randomized controlled trial; Level 4, no evidenceone low quality randomized controlled trial, no randomized control trials, or contradictory results among different trials.
Several other systematic reviews have adopted this approach [18, 19]. Consistency was defined a priori as over 60% of the trials agreeing on the direction of the results. For our overall conclusion, we also considered other issues, such as quality of the original studies, adequate sample size, and precision of the studies other than just the actual proportion of positive studies. Quality of the studies was determined with the Jadad scale of validity assessment [20], as described below.
Assessment of validity
The quality of the randomized controlled trials was assessed using Jadad's scale [20, 21]. Two reviewers independently rated the quality of the studies. If there were any disagreements, they were resolved through consensus by discussion and clarification of different opinions. If disagreements continued, they were resolved through arbitration by a third reviewer. The calculated kappa value was 0.72. The Jadad scale determined the quality of the trials [20, 21]. Trials were classified as higher quality if their scores were 3 or higher and as lower quality if their scores were 2 or lower on the five-point Jadad scale. When using the Jadad scale, studies were each given a point for randomization, appropriateness of randomization, double-blinding, appropriateness of blinding, and mentioning withdrawals and dropouts [22]. According to Jadad [21], successful double-blinding requires that the participants and the investigators assessing the intervention outcome are unaware of the intervention each participant is to receive.
![]() |
Results |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
|
![]() |
Discussion |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Although all the studies used acupuncture as the primary intervention, the type of acupuncture administered appeared to be different in terms of dosing, such as the total number of treatments, frequency and duration of treatments, number of needles being used and the type of acupuncture (classical vs anatomical), etc. Therefore, the interventions were also heterogeneous.
The third area of heterogeneity identified was the outcomes used. There was no uniform definition of pain relief. Even though pain relief is important, especially from the patient's perspective, it is rather subjective. More objective measures, such as recovery of function and returning to work, were also important variables. Although Davidson's study [4] examined the recovery of function, no other study addressed the issue of returning to work. Looking at pain relief itself, there was great variability among these studies in terms of the definition of improvement for pain relief. In particular, the definition of short-term pain alleviation varied from immediately after one treatment to 3 months after a series of treatments. Nevertheless, even after we took the sample size, quality of the treatment protocol and quality of the research methodology into consideration, the evidence continued to support acupuncture's ability to alleviate epicondyle pain.
Furthermore, there is much debate at the moment in regard to what defines a reasonable sham control [25]. The selected studies used various sham controls (or sham acupuncture), including superficial needling [22], suggestive needling (stimulating the area with a pencil-like probe to simulate needle insertion and extraction) [23] and needling at non-traditional points [14; D. Irnich, H. Karg, N. Behrens, M. A. Schreiber, M. Krauss, P. Kroling, personal communication]. Sham acupuncture might in fact produce non-specific analgesic effects. According to Ezzo et al. [19], the proportion of improvement reported in the sham groups was significantly higher than that reported in inert placebo groups. However, in Ezzo's review, no studies specifically examining lateral epicondyle pain were included. Research is ongoing and will hopefully will one day give clearer guidance for the selection of appropriate sham controls [2628]. Finally, the sample size in the studies was small, the largest sample of 82 patients being in the study of Haker and Lundeberg [22].
Future research is recommended to resolve the issues discussed. There is a need for a larger scale multicentre study that will also address the issue of adequate sham control, uniformity of the definition of lateral epicondylitis, optimal acupuncture treatments, and the use of more objective outcomes.
![]() |
Conclusion |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
The authors have declared no conflicts of interest.
|
![]() |
References |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|