Knee pain may be the result of an injury, such as a ruptured ligament or torn cartilage, meniscus. Medical conditions including arthritis, gout and infections. Physical therapy and knee braces also can help relieve knee pain. In some cases, your knee may require surgical repair. Signs and symptoms that sometimes accompany knee pain include: Swelling, stiffness, Redness, warmth to the touch, Weakness or instability, Popping or crunching noises, "Locking," or inability to fully straighten the knee.