99 patients scheduled for primary total knee arthroplasty were randomized to kinematic alignment with the use of patient-specific cutting blocks (PSCB), or mechanical alignment with the use of computer navigation (NAV). The purpose of this study was to compare alignment and functional outcomes between the two groups. Results demonstrated that, while significant differences were noted between groups in terms of alignment of individual components, there were no significant differences between groups in overall coronal lower limb alignment postoperatively or change in functional outcome over 2 years.