Aims: Nonunion still remains a major complication after skeletal trauma or elective surgery. In the last decade, extracorporeal shock wave therapy has become a common tool for treatment of nonunions and was even referred to as treatment of þrst choice for this condition. But so far, no prospective, randomised trial was conducted to show efþciency of this form of treatment. Methods: This study was performed to determine the value of extracorporeal shock wave therapy for the treatment of nonunions. Previous published results in literature and own clinical results of 73 consecutive patients with nonunions, treated with extracorporeal shock waves, were analysed and confronted with natural history of union. Results: Concordant to literature, union was achieved in more than 55% of treated patients; better results were achieved for hypertrophic type of nonunion (61.8%). Mean time between shock wave therapy and bony consolidation was 5.3 months, ranging from 1 to 16.5 months. Conclusions: No study could prove efþciency of extracorporeal shock wave therapy on bone healing. Clinical studies, reporting acceleration of union after application of shock waves, rather seem to misinterpret natural history of union. No evidence is given for treatment of pseudarthroses with extracor-poreal shock waves. A randomised prospective clinical trial with control group has to be performed to take a þnal decision about this indication for extracorporeal shock wave therapy.