[Quantitative determination of the effect of induced alternating currents on the integration of autologous spongiosa transplants].

In a right-left experiment on the ulna of beagles, the authors investigate the influence of induced alternating current on the number of healed-in autologeous spongiosa grafts taken from the same side of the body. At first an atrophic pseudarthrosis is produced in both ulnae of twenty animals by bone resection and electrocoagulation over six months. Following to spongiosa transplantation and plate osteosynthesis, the ulnae are stimulated during eight weeks with a sinusoidal current of 38 cps and an electromagnetically induced alternating-current voltage of 600 mV on an average. The blindfold evaluation of the X-ray picture is performed by four experts and shows significantly better results in the stimulated side. By variance analysis of the results of electronic planimetry of serial layers in the region of transplantation represented by microradiography, it is demonstrated that the greater bone density of the stimulated grafts compared to the control grafts is statistically significant. It has to be considered that these results refer strictly to the electric data and treatment times applied by the authors. Particularly the results are not valid for the unique application of electromagnetic fields without alternating-current component.