Effects of low voltage pulsed current on edema formation in frog hind limbs following impact injury.

The purpose of this study was to test the effect of low voltage pulsed current (LVPC) on posttraumatic edema formation in frog hind limbs. Feet of 26 anesthetized bullfrogs were systematically injured by weight drop. One hind limb of each animal was randomly selected to receive continuous 100-pps LVPC at 90% of motor threshold; the opposite hind limb served as a control. A series of four 30-minute treatments (interrupted by 30-minute rests) was begun minutes after injury. Changes from pretrauma limb volumes were determined before and after each treatment and at 8, 17, 20, and 24 hours posttrauma. Analysis of variance revealed no significant treatment effect. Similar studies utilizing high voltage pulsed current (HVPC) at 90% of motor threshold revealed significant curbing of edema formation in frogs. Waveform (LVPC versus HVPC) seems to influence the efficacy of electrotherapy for edema control.