Position a stability ball in the small of the back and the wall. Next, ensure the stance leg’s foot is in a position that is far enough away from the wall so the knee will remain in good alignment throughout the squatting motion. Flex the non-stance knee to 90 degrees.
With the arms resting at the sides, slowly squat down on the stance leg in a slow controlled motion in a stable, pain-free range of motion. The uninvolved leg will simply stay flexed with the foot moving posteriorly toward the wall during the descent. Ideally, the unsupported foot should not touch the wall or floor. Pause at the bottom for 1-2 seconds and then return to the start position. Repeat for 10 repetitions and then switch legs. Perform 2-3 sets.