The review assessed the effectiveness of extra corporeal shock wave therapy (ESWT) in patients with plantar heel pain. This was a well-conducted review and the authors' conclusion, that the results does not support the use of ESWT for plantar heel pain in clinical practice, seems justified.

To determine the effectiveness of extracorporeal shock wave therapy (ESWT) in patients with plantar heel pain.

The Cochrane Musculoskeletal Injuries Group Specialised Register of trials (August 2003), the Cochrane CENTRAL Register (Issue 3, 2003), MEDLINE (1966 to September 2004), EMBASE (1982 to September 2004) and CINAHL (1982 to September 2004) were searched; the search terms were reported. In addition, bibliographic references of relevant articles and dissertations were checked. Studies reported in languages other than English were also included.

Study designs of evaluations included in the review

Randomised controlled trials (RCTs) were eligible for inclusion.

Specific interventions included in the review

Studies comparing ESWT with placebo, or comparing differing doses of ESWT, were eligible for inclusion.

Participants included in the review

Studies of individuals of any age with a clinically confirmed diagnosis of plantar heel pain were eligible. Treatment of patients with plantar heel pain arising from calcaneal fractures, calcaneal tumours, previous surgery for plantar heel pain or posterior heel pain was excluded. The included trials were in adults from the general population, athletes, or individuals with seronegative arthropathies and enthesopathies. Most of the participants had had plantar heel pain for more than 6 months.

Outcomes assessed in the review

The primary outcome considered in the review was morning pain (pain on first rising, first step pain or start up pain). The secondary outcomes included walking pain, pressure pain, disability, quality of life and adverse events.

How were decisions on the relevance of primary studies made?

Two reviewers independently reviewed identified papers for selection in the review.

A predefined check list was used to evaluate the quality of the primary studies. This assessed randomisation, allocation concealment, intention-to-treat analysis, blinding and follow-up. A maximum quality score of 6 could be allocated. Studies scoring four or more points were considered to be of high quality. Two reviewers independently assessed the primary studies for validity.

Two reviewers extracted the data from the primary studies; any disagreements were resolved through discussion. Attempts were made to contact the authors of the primary studies for additional information.

How were the studies combined?

Weighted mean differences (WMDs) for morning pain, and their 95% confidence intervals (CIs), were pooled in a meta-analysis using a fixed-effect model. Studies reporting other outcomes were combined in a narrative. A funnel plot was used to assess publication bias.

How were differences between studies investigated?

Chi-squared tests and the I-squared statistic were used to assess the heterogeneity of trials combined quantitatively. Sensitivity analyses looking at trial quality were performed. Clinical differences between the trials were reported in tabular format.

Eleven RCTs (n=1,290) were included. Six of these were included in the meta-analysis (n=980).

Compared with placebo or a therapeutically low dose, ESWT reduced reports of morning pain at 12 weeks (WMD 0.42, 95% CI: 0.02, 0.83; based on 6 RCTs, n=881). No significant heterogeneity was found (P=0.11). No statistically significant effect of ESWT was shown when the lowest quality trials were excluded from the analyses (WMD 0.21 cm, 95% CI: -0.29, 0.70; based on 4 RCTs); no statistically significant heterogeneity was found.

Of the eight trials reporting walking pain, five demonstrated a favourable outcome after treatment with ESWT.

Four of the five trials reporting pain on pressure demonstrated a favourable outcome after treatment with ESWT.

Data on resting and night pain were collected, but they are not considered common symptoms of heel pain. Two studies reported minimal adverse effects. The most common adverse effect with ESWT was pain, both during and after the treatment (4 RCTs).

This review did not support the use of ESWT for plantar heel pain in clinical practice. ESWT was effective for the treatment of plantar heel pain, but the effect size was small; when only high-quality trials were considered, this effect was not shown to be statistically significant.

A clear review question was presented with well-defined inclusion and exclusion criteria. Several electronic databases were searched, without apparent language restriction, and publication bias was assessed. The procedures implemented to select papers, extract the data and assess quality were likely to minimise error or bias. The quality of the primary studies was assessed using an appropriate tool, and the results of this assessment were reported in full. The statistical analysis appeared appropriate and the authors explored some differences in the characteristics of the selected studies. The authors acknowledged that information on 24% of the dataset were unavailable for the outcomes of interest. This was a well-conducted trial and the authors' conclusions are likely to be reliable.

Practice: The authors stated that the results do not support the use of ESWT for plantar heel pain in clinical practice.

Research: The authors stated that future trials should report sufficient detail in terms of measurement scores, variance, WMDs and CIs, to allow inclusion in meta-analyses. In addition, future trials should include outcomes of disability and impact on health-related quality of life.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.