Fracture of the humerus represents a common problem among the young and elderly populations. Although humerus fractures usually heal uneventfully, nonunions can sometimes occur. We present a case of humeral nonunion managed with shock wave therapy in the outpatient setting. A 62-year-old woman with a closed comminuted fracture of the proximal third of the humerus came to our attention 6 months after the trauma with a hypertrophic nonunion. Radiographs showed a hypertrophic callus with a fracture gap of 4 mm. We performed ten shock wave treatments in the outpatient department, with an interval of 60 days between each single treatment. Each session consisted of 2000 impulses at 0.86 mJ/mm 2 applied in two planes. No anesthesia was given during the treatment. The patient received a sling to support the treated arm during the first days following each treatment. Follow-up assessment by radiographic and physical examination, performed after 4 weeks and at 3, 6, 12, 18 and 24 months, showed complete bony union and cortical bridging, achieved at the end of the treatment. We believe that this method is a safe and effective alternative to surgery for the treatment of chronic hypertrophic nonunions.Moreover, in case such treatment is unsuccessful, subsequent surgery is not precluded.