Background: Patients undergoing TKA are constantly increasing and some of them are not satisfied with the outcome of surgery. There are many factors that may predispose to dissatisfaction in those patients. We studied whether patient's psychological status, implant type or BMI had predicted poor outcome after TKA at the JRMS. Methods: We performed our study on 189 TKA in 158 patients to assess the effect of the above-mentioned factors and their relation to the patient's satisfaction at 1 year after surgery. Two surgeons independently applied the Likert's satisfaction Score system, however, all surgeries were performed by one surgeon. Outcomes generally included postoperative pain, dissatisfaction, or loss of function of the patients. Results: Overall, we found the satisfaction rate to be 81% in this study. We elaborated a noticeable difference between those who are satisfied and who are dissatisfied after having a look at the Likert satisfaction scoring system. Dissatisfied patients had a higher risk of anxiety, depression, less range of motion, more pain, and a lower life quality. The developed prediction tool consists of 5 simple but robust questions. The sensitivity of prediction satisfaction tool was 94% with a positive-predictive value of 89%. Conclusions: We found that a poor preoperative psychological status of a patient, higher BMI, greater than 40, might affect the post-operative satisfaction of a TKA. We also came to the conclusion of a satisfaction rate of 81% of all the TKA patients at the JRMS with the preoperative psychological factor being the most significant factor affecting the rate of post TKA satisfaction based on the used questionnaire with no significant effect of implant type.