Total Knee Replacement (TKR): How it Works Total knee replacements are one of the most successful procedures in all of medicine. A total knee replacement - also known as total knee arthroplasty (TKA) -substitutes metal for the articular surfaces of the bones, thus alleviating the chronic arthritic pain. Outcomes for knee replacement surgery are excellent. This procedure eliminates or significantly reduces pain while increasing function. Joint replacement surgery is a safe and effective procedure