Introduction: Deforming arthrosis, or osteoarthritis, is the most common rheumatic disease that involves the musculoskeletal system. The purpose of this research is to perform a retrospective review of the quality of life of patients with knee arthrosis, who underwent total knee arthroplasty (TKA) no less than five years ago, to evaluate, based on the Knee Society Scoring System, the efficacy of a modified measured resection technique, and to investigate factors that affect the outcomes. Material and methods: The research sample consisted of 44 patients who had severe osteoarthrosis, Kellgren-Lawrence grade III and grade IV. Results: The post-operative complications occurred in seven knee joints. Among them there were two cases of infection, two cases of periprosthesis fracture, and two cases of aseptic instability, each pair accounting for 4.3%, and one case of femoropatellar pain (2.3%). The remaining 38 knee joints (84.8%) were free of complications. Conclusions: Knee arthrosis is a serious health problem, given the significant rate of disability among patients and the significant reduction in the quality of life. Patients often seek medical help at the later stages of the disease, when pain is strong and knee function is significantly reduced. The approach to rehabilitation procedures and, in some cases, to lifestyle improvement should be more responsible.