 Detailed observational data will be collected during the surgical procedures, and participating patients will be evaluated at prescribed intervals pre-operatively, and 2,4,6, and 12 months post-operatively using survey instruments, clinical indicators, and routine radiologic outcomes. Radiologic outcomes will be assessed using standard x-rays that are obtained in the course of normal care for all patients who undergo total knee arthroplasty TKA. A subset of the first 30 patients enrolled into each treatment arm will, in addition, be asked to voluntarily undergo a computed tomography CT scan of the lower extremity hip, knee, and ankle joints 8-12 weeks after surgery to measure 3-dimensional accuracy of prosthesis placement and limb alignment. 