Abstract: This invention comprises a knee brace for controlling knee instability and minimizing risk of injury to the knee in all types of sports. The mechanical hinge has the same kinematics as the human knee, allowing the knee brace to conform to the upper and lower leg throughout its range of motion. The knee brace includes a femoral brace and a tibial brace joined by unique variable axis hinges wherein arcuate slots are formed in each link with respective followers disposed on opposing links to provide rotation and slide movement between the femur and tibia resulting in the same path of the center rotation as the human knee. The femoral brace is conformed to the upper leg to provide maximum stability and protection. The tibial brace is conformed to the tibia tubercle, just below the patella and frontal area of the tibia, to provide maximum stability and protection therefor.