Effect of lithotripsy on immature rabbit bone and kidney development

Although extracorporeal shock waves have been used to treat kidney stones for several years, little is known to their effect on developing tissue. In order to determine if lithotripsy has any negative effects on development, immature rabbits were used to study the relationship of extracorporeal shock waves to renal and skeletal growth. Rabbits in both the control and treatment groups had metallic clips placed surgically to demarcate the kidneys. Following unilateral kidney and femoral head treatment of the respective study groups with the Dornier Lithotripter Model HM-3, the rabbits were allowed to grow to maturity (six months). Plain radiographs were taken at three months. There was no significant difference between control and study groups when length of the kidneys or femurs, the diameter of the femoral heads, or the rabbits weights were compared. At six months of age, the rabbits were weighed, then sacrificed. The kidneys and femurs were removed. Comparisons between the control and study groups were then made for weight of the rabbit, weight and volume of the individual kidneys, femoral length, and femoral head diameter. Following these measurements sectioning and histologic examinations were done. In all parameters grossly and histologically, there was no statistically significant difference. It is concluded from this study that treatment with extracorporeal shock waves does not adversely affect overt rabbit renal or bone growth, making treatment of pediatric patients with ESWL appear safe in regard to these parameters. Future studies will be directed at confirming these findings in children.