The posterior tibial slope affects the measurement reliability regarding the radiographic parameter of the knee.

"Declarations Ethical approval and consent to participateThis study was ethically approved by the Institutional Review Board (IRB) of Hallym University Sacred Heart Hospital (IRB No. 2022-12-015). All methods were carried out in accordance with the relevant guidelines and regulations of the IRB and the 1964 Helsinki Declaration. Informed consent from the patients was not required owing to the retrospective nature of the study. Consent for publicationNot applicable. Conflict of interestThe authors declare that they have no conflicts of interest. Competing interestsThe authors declare no competing interests. Conflict of interest The authors declare that they have no conflicts of interest. Competing interests The authors declare no competing interests."

"Funding This research was supported by Hallym University Research Fund 2023 (HURF-2023-18)."