EFFECTS OF DIFFERENT LEVELS OF DIRECT-CURRENT ON EARLY LIGAMENT HEALING IN A RAT MODEL

Electrical stimulation has been shown to enhance the repair of biologi cal tissues such as bane and tendon. The objective of this study was t o determine whether low level direct current enhances the early healin g of injured medial collateral ligaments. Eighty-seven rats were divid ed into three groups on the basis of the level of current delivered. A ll underwent transection of the medial collateral ligament bilaterally . The experimental medial collateral ligaments received current (which varied by group), while the contralateral medial collateral ligaments (the controls), with identical electrodes, received no current. After 12 days, each ligament was tested biomechanically with use of a hydra ulic materials testing machine. Group 1 (8.6 +/- 5.9 mu A) showed stat istically significant improvements in maximum rupture force, energy ab sorbed, stiffness, and laxity The groups that had received lower level s of current did not show significant improvements. In this study, sti mulation of 1-20 mu A was the most effective level of direct current f or the enhancement of early healing of the medial collateral ligament.