Cortisone injections: Injections of a corticosteroid into your joint might relieve pain for a few weeks. Your doctor numbs the area around your joint, then places a needle into the space within your joint and injects medication.
Lubrication injections: Injections of hyaluronic acid might relieve pain by providing some cushioning in your knee, though some research suggests that these injections offer no more relief than a placebo. Hyaluronic acid is similar to a component normally found in your joint fluid.
Realigning bones: If osteoarthritis has damaged one side of your knee more than the other, an osteotomy might be helpful. In a knee osteotomy, a surgeon cuts across the bone either above or below the knee, and then removes or adds a wedge of bone. This shifts your body weight away from the worn-out part of your knee.
Joint replacement: In joint replacement surgery, your surgeon removes your damaged joint surfaces and replaces them with plastic and metal parts. Surgical risks include infections and blood clots. Artificial joints can wear out or come loose and might eventually need to be replaced.
Courtesy: Mayo Clinic