2. Materials and Methods
primary knee osteoarthritis, weight loss, TKA
A retrospective cohort study design was planned to include patients over 65 years of age who had undergone unilateral TKA for primary knee osteoarthritis between February 2011 and September 2015 in Tekirdağ Yasam Hospital Orthopedics and Traumatology Clinic, Tekirdağ, Turkey. Ethical approval for the present study was obtained from the Clinical Research Ethics Committee, Faculty of Medicine, Namık Kemal University, Tekirdağ, Turkey (approval no.: 2021.114.04.09). All the patient data from the hospital’s medical records were obtained for this retrospective study without extracting personal identification details. The study was conducted in accordance with the Declaration of Helsinki; all the patients provided written informed consent to participate in the study and to the use of their data for scientific purposes by contacting them again.The indications for TKA included patients’ non-response to conservative treatments for primary knee osteoarthritis (drugs, physical therapy, weight loss, etc.) [A total of 144 patients were screened for inclusion in the study; among them, 21 refused to participate or could not be reached, and 17 were excluded due to the presence of comorbidities. Based on the findings obtained from this study, when a difference of 150 units between the means and standard deviations of 200 and 300, respectively, was considered, the statistical power of the study was determined to be 85% at a 95% confidence level and a significance level of 0.05. The study included a sample size of n1 = n2 = 52, with a total sample of The patients were further randomly divided into two groups (