This retrospective real-world study aims to compare the medium- and long-term clinical outcomes, safety, and economic benefits of different knee prosthesis brands used in primary unilateral total knee arthroplasty (TKA) at our hospital. The study will include adult patients who underwent first-time unilateral TKA between January 1, 2022 and December 31, 2025. Outcomes such as postoperative knee function, complications, length of hospital stay, quality of life, and medical costs will be evaluated. The results are expected to provide evidence to support prosthesis selection and optimize healthcare resource allocation.