[The value of shockwave therapy in treatment of humero-radial epicondylitis]

Shock wave therapy for lateral elbow pain

BACKGROUND

This review is one in a series of reviews of interventions for lateral elbow pain.

OBJECTIVES

To determine the effectiveness and safety of extracorporeal shock wave therapy (ESWT) for lateral elbow pain.

SEARCH STRATEGY

Searches of the Cochrane Controlled Trials Register (Cochrane Library Issue 2, 2004), MEDLINE, EMBASE, CINAHL, and Science Citation Index (SCISEARCH) were conducted in February 2005, unrestricted by date.

SELECTION CRITERIA

We included nine trials that randomised 1006 participants to ESWT or placebo and one trial that randomised 93 participants to ESWT or steroid injection.

DATA COLLECTION AND ANALYSIS

For each trial two independent reviewers assessed the methodological quality and extracted data. Methodological quality criteria included appropriate randomisation, allocation concealment, blinding, number lost to follow up and intention to treat analysis. Where appropriate, pooled analyses were performed. If there was significant heterogeneity between studies or the data reported did not allow statistical pooling, individual trial results were described in the text.

MAIN RESULTS

Eleven of the 13 pooled analyses found no significant benefit of ESWT over placebo. For example, the weighted mean difference for improvement in pain (on a 100-point scale) from baseline to 4-6 weeks from a pooled analysis of three trials (446 participants) was -9.42 (95% CI -20.70 to 1.86) and the weighted mean difference for improvement in pain (on a 100-point scale) provoked by resisted wrist extension (Thomsen test) from baseline to 12 weeks from a pooled analysis of three trials (455 participants) was -9.04 (95% CI -19.37 to 1.28). Two pooled results favoured ESWT. For example, the pooled relative risk of treatment success (at least 50% improvement in pain with resisted wrist extension at 12 weeks) for ESWT in comparison to placebo from a pooled analysis of two trials (192 participants) was 2.2 (95% CI 1.55 to 3.12). However this finding was not supported by the results of four other individual trials that were unable to be pooled. Steroid injection was more effective than ESWT at 3 months after the end of treatment assessed by a reduction of pain of 50% from baseline (21/25 (84%) versus 29/48 (60%), p<0.05). Minimal adverse effects of ESWT were reported. Most commonly these were transient pain, reddening of the skin and nausea and in most cases did not require treatment discontinuation or dosage adjustment.

AUTHORS' CONCLUSIONS

Based upon systematic review of nine placebo-controlled trials involving 1006 participants, there is "Platinum" level evidence that shock wave therapy provides little or no benefit in terms of pain and function in lateral elbow pain. There is "Silver" level evidence based upon one trial involving 93 participants that steroid injection may be more effective than ESWT.

Shock wave therapy for lateral elbow pain

BACKGROUND

This review is one in a series of reviews of interventions for lateral elbow pain. Lateral elbow pain, or tennis elbow, is a common condition causing pain in the elbow and forearm and lack of strength and function of the elbow and wrist. Shock wave therapy (ESWT) involves the application of single pulsed acoustic wave. Since the 1990's reports of benefit of ESWT in the treatment of tendon disorders have been appearing in the literature. A systematic review published in the German language appeared in 2000 (Boddeker 2000)

OBJECTIVES

To determine the effectiveness and safety of ESWT in the treatment of adults with lateral elbow pain.

SEARCH STRATEGY

Comprehensive electronic searches of MEDLINE, CINAHL, EMBASE and SCISEARCH were combined with searches of the Cochrane Clinical Trails Registrar and the Musculoskeletal Review Group's specialist trial database. Identified keywords and authors were searched again in an effort to identify as many trials as possible.

SELECTION CRITERIA

Two independent reviewers assessed all identified trials against pre-determined inclusion criteria. Randomised and pseudo randomised trials in all languages were evaluated for inclusion in the review provided they described individuals with lateral elbow pain and were comparing the use of ESWT as a treatment strategy.

DATA COLLECTION AND ANALYSIS

For continuous variables means and standard deviations were extracted or imputed to allow the analysis of weighted mean difference. Weighted mean difference using a random effects model was selected when outcomes were measured on standard scales. A fixed effects model was used to interpret results and assess heterogeneity. For binary data numbers of events and total population were analysed and interpreted as relative risk.

MAIN RESULTS

Two trials of ESWT versus placebo are included in this review (~~Rompe 1996~~, ~~Haake 2001~~). Both trials included similar study populations consisting of participants with chronic symptoms who had failed other conservative treatment. The frequency of ESWT application and the doses and techniques used were similar in both trials. The first trial demonstrated highly significant differences in favour of ESWT whereas the second trial found no benefits of ESWT over placebo. When the data from the two trials were pooled, the benefits observed in the first trial were no longer statistically significant. The relative risk for treatment failure (defined as Roles-Maudsley score of 4) of ESWT over placebo was 0.40 (95% CI, 0.08 to 1.91) at six weeks and 0.44 (95% CI, 0.09 to 2.17) at one year. After 6 weeks, there was no statistically significant improvement in pain at rest [WMD pain out of 100 = - 11.40 (95% CI, -26.10 to 3.30)], pain with resisted wrist extension [WMD pain out of 100 = -16.20 (95% CI, -47.75 to 15.36)] or pain with resisted middle finger extension [WMD pain out of 100 = -20.51(95% CI, -56.57 to 15.56)]. Results after 12 or 24 weeks were similar.

REVIEWER'S CONCLUSIONS

The two trials included in this review yielded conflicting results. Further trials are needed to clarify the value of ESWT for lateral elbow pain.