Why is this trial needed now? Current technological advances in knee arthroplasty surgery have allowed surgeons to implant TKA with considerable accuracy. We however are not sure if the position we are placing the knee in is the "correct" position for most patients. It is thought that the relatively high percentage of patients that are not completely satisfied with the outcome of their knee replacement may have the implants in a suboptimal position for that individual patient. The traditional mechanical alignment may not be the optimal position for these patients. The anatomical alignment technique may reduce the percentage of dissatisfied patients. Implant companies with this technology are currently marketing this to surgeons and patients without clinical data to support this claim. There is also the possibility that placing an artificial knee joint in an anatomic position may impart a negative impact on longevity of the implant, thus increasing early revision rates and the significant health costs associated with this. Thus it becomes mandatory to evaluate this new technology before its widespread adoption in clinical practice to determine the real benefits or disadvantages of changing from a successful clinical practice (mechanical alignment) used over the last 40 years.