Context: Published data on extracorporeal shock wave therapy (ESWT) for heel pain provide controversial evidence about the clinical effectiveness. In previous studies, three interventions of ESWT without local anaesthesia demonstrated excellent outcome.
Objective: To give confirmatory proof of effectiveness and safety of focused ESWT administered without local anaesthesia in the treatment of chronic painful heel syndrome.
Design and Participants: Prospective, double-blind, randomized, placebo-controlled multicenter FDA trial conducted among 250 patients.
Interventions: ESWT (0.25 mJ/mm2) or placebo. Both groups received three interventions of 2000 shock wave impulses, each session 1 week apart.
Main Outcome Measures: The primary outcome was the percentage change of heel pain quantified by VAS composite score, as well as the change of Roles and Maudsley score at 12 weeks after the last intervention compared to baseline. Secondary endpoints were defined as single success rates (more than 60% reduction of morning pain, pain at daily activities, and pain with force-meter), overall success rate, physician’s judgment of effectiveness; patient’s satisfaction with outcome, patient’s willingness to recommend treatment, and subject’s analgesic medication consumption.
Results: Follow-up was excellent with 246 patients (98.4%) available for intention-to-treat analysis at 12-week follow-up. ESWT resulted in a 69.2% reduction of heel pain regarding the primary endpoint VAS composite score compared to baseline, compared to 34.5% for placebo (p=0.0027, one-sided). ESWT was also significantly superior to placebo for the Roles and Maudsley score (p=0.0006, one-sided). The combined overall result of the eight secondary criteria also showed statistical significance (P = 0.0015 one-sided, multivariate directional Wilcoxon-Mann-Whitney test). No clinically relevant device-related adverse events were recorded.
Conclusion: The results of the present study provide confirmatory proof of effectiveness of ESWT without local anaesthesia in the treatment of refractory painful heel syndrome.