Dear Patient, Welcome, and thanks for sharing your concern I went through your query, and I feel, if your joints are damaged to the extent that you need constant dose of analgesics, than it is better to go for knee replacement, as too much of analgesics can cause damage to your kidneys and stomach, which can be more dangerous. so if you feel pain is not under control with exercises, better go for knee replacement. I hope my advice would have been useful, in decision making regarding your treatment, still if you have any clarifications or doubts feel free to contact back. Thanks.