NEW DELHI, March 24 -- No matter how much we want to avoid it, a knee replacement is the only reliable solution for endstage osteoarthritis or rheumatoid arthritis. With increasing life expectancy, the chances of getting a problematic knee have become higher - in the past 10 years, total knee replacement trumped coronary artery bypass graft surgery as the most common major surgery performed in the developed world. In spite of the modern medical technologies making knee replacement surgeries successful and easier than before, postoperative pain remains a major concern....