HIGH-ENERGY SHOCK-WAVES FOR THE TREATMENT OF NONUNIONS - AN EXPERIMENT ON DOGS

Several surgical as well as nonsurgical modes of treatment of nonunion s have been advocated in the literature. In an effort to achieve bony union in a new noninvasive way, we experimentally investigated the tre atment of nonunions with extracorporeally induced high-energy shock wa ves. With use of a modified canine nonunion model, two randomized grou ps of five dogs each were set up to obtain a treatment and a control g roup. Shock waves were applied with the Osteostar (Siemens A.G., Germa ny), a specially designed, experimental, transportable, high-energy sh ock wave apparatus. Each of the dogs in the treatment group received 4 000 shock waves of 0.54 mJ/mm(2) (14.5 kV), which were applied at four preselected sites, lying symmetrically on the dorsal and ventral side s of the nonunion. During the course of the experiments, the dogs were monitored radiographically. Immediately after the shock wave treatmen ts no radiographic changes could be detected. All of the treatment gro up dogs reached radiographically observable bony union 12 weeks after the shock wave treatment. In the control group, four dogs had radiogra phically persistent nonunions at termination of the study. Statistical analysis with Fisher's exact test (two-sided; P less than or equal to 0.05) demonstrated the significance in outcome between the two groups . We conclude that hypertrophic nonunions in dogs can be treated succe ssfully with extracorporeally induced high-energy shock waves. The res ults of this study may justify the application of shock waves for the treatment of certain types of nonunions, provided a specially designed shock wave apparatus is used for this purpose. We think that it may b ecome a reliable, nonsurgical, alternative for the treatment of certai n types Of nonunions. (C) 1994 Academic Press, Inc.