Plies
This exercise works the inner as well as outer thighs, and does not place a lot of stress on the joints either. To do this exercise, stand with your feet a little more than shoulder width apart. Turn your feet out (such that they imitate a duck's feet), then slowly lower yourself, such that your thighs are almost parallel to the floor. Hold this position for a few seconds. Slowly come back to the starting position and repeat the exercise for 10-12 repetitions, 3 sets each.