The efficacy of extracorporeal shock-wave therapy for tennis elbow was investigated using a single fractionated dosage in a randomised, double-blind study. Outcomes were assessed using the Disabilities of Arm, Shoulder and Hand questionnaire, measurements of grip strength, levels of pain, analgesic usage and the rate of progression to surgery. Informed consent was obtained before patients were randomised to either the treatment or placebo group. In the final assessment, 74 patients (31 men and 43 women) with a mean age of 43.4 years (35 to 71), were included. None of the outcome measures showed a statistically significant difference between the treatment and control groups (p > 0.05). All patients improved significantly over time, regardless of treatment. Our study showed no evidence that extracorporeal shock-wave therapy for tennis elbow is better than placebo