Because a total knee replacement is an elective surgery, there are no serious or life-threatening consequences associated with not having it. However, it is important to understand what may result from this decision.
Currently, no medicine has been developed that can reverse the process of a joint wearing out. There are medicines and treatments that slow the process. However, the knee joint does not heal by itself when arthritis is present. With this in mind, patients with knee arthritis and pain generally do not get better with time, and often only experience these symptoms getting worse. In the end, it is your choice whether the disability caused by the arthritis is bothersome enough to have this surgery.
The final decision to have or not have surgery rests with you, but all concerns relating to this decision should be discussed with your doctor at length. Then you and your doctor can come up with a treatment method that is comfortable for you.