According to the Public Health Institute of Vojvodina one of the main causes of morbidity, invalidity and absence from work in Vojvodina are musculoskeletal diseases. Osteoarthritis is a multifactorial joint disease, with catabolism and inflammation in its background. For radiological classification of knee osteoarthritis stage Kellgren-Lawrence scale is used. It consists of five levels, from stage "0" to stage "4". The goal of osteoarthritis treatment is to reduce pain and muscle spasms, improve limb function, prevent joint contractures and train patients to function in everyday life and professional activities. The therapy is divided into conservative (medical and physical) and surgical. Arthroplasty is a surgical procedure that involves destruction of articular surfaces and replacement of degenerative joints with endoprostheses, which result in increased general and working ability. Modern endoprostheses enable a high success rate of the procedure. At the Department of Orthopedics and Traumatology, Clinical Center of Vojvodina in Novi Sad, the first knee aloarthroplasty was performed in 1989. Since then, more than 3000 knee aloarthroplasties have been done. Clinical patient evaluation was obtained through subjective status, functional evaluation and use of scoring systems. More than 80% of patients had a good or a great score.