Knee pain is a common complaint that affects people of all ages. Knee pain may be the result of an injury, such as a ruptured ligament or torn cartilage. Knee pain can also have causes that aren't due to underlying disease. Examples include heavy physical activity, lack of use, injuries such as sprains or strains, sitting in a constrained area, or sitting on knees for a prolonged period. If the symptoms companies Swelling and stiffness, Redness and warmth to the touch, Weakness or instability, Popping or crunching noises, Inability to fully straighten the knee. All these symptoms indicate your knee pain is not light and recommend seeking immediate therapy session as possible.