Unanswered questions regarding indications for device.

The purpose of this study is to evaluate and compare implant kinematics of conventional mechanically aligned and anatomically aligned total knee arthroplasties (TKA) at 1 year post-operatively.

Participants will be randomized to receive a primary TKA using either an anatomic alignment or a conventional mechanical alignment technique.

Participants will undergo a kinematic analysis of a deep knee bend using single-plane fluoroscopy at 1 year post-operatively. The primary outcome will be based on the 6 degree of freedom kinematics and associated joint component proximity during the knee bend task. Secondary outcomes include the Knee Society Score, the Knee Injury and Osteoarthritis Outcome Score, and the Forgotten Knee Score.

Inclusion Criteria:

• Males and females
• Primary arthroplasty for treatment of osteoarthritis
• Age between 40 and 80 years old
• Willingness to provide written consent for study participation

Exclusion Criteria:

• Revision arthroplasty
• Pre-operative knee flexion lower than 90 degrees
• Varus knee deformity greater than 15 degrees
• Pre-operative valgus knee deformity
• Presence of infections, highly communicable diseases or metastatic disease
• Significant neurological or musculoskeletal disorders or disease that may interfere with normal gait or weight bearing
• Congenital, developmental, or other bone disease or previous hip surgery that may, in the surgeon's judgment, interfere with total knee prosthesis survival or success
• Presence of previous prosthetic knee or hip replacement device
• BMI > 40
• Pregnant women