I found the best way to remove plaques from areas like the elbows and knees is to moisturize with your favorite lotion then cover it so the plaques can soften. You can use plastic wrap but I have elbow sleeves that hold in the moisture. You leave them on for a few hours and then when you shower, the plaques rub right off.
Editor’s note: Special occlusion wraps or bandages can be purchased in a variety of shapes and sizes from local or online medical supply stores. Prescription treatments should not be occluded (wrapped) without consulting with your doctor/pharmacist.