Comparison of Two Robotic-Assisted Total Knee Arthroplasty Systems

Inclusion Criteria: * Patient must be a candidate for primary TKA (either Stryker Triathlon with MAKO Robotic-Arm or DePuy Attune with VELYS Robotic-Assistance). * Individuals who are able to speak, read, and comprehend the Institutional Review Board approved Informed Consent Document and willing and able to provide informed patient consent for participation in the study and have authorized the transfer of information to the Sponsor. * Individuals who are willing and able to complete follow up visits, questionnaires, and radiographic evaluations as specified by the study protocol. * Individuals who are male or non-pregnant female age 18-80 years at time of device implantation. * Patient has a diagnosis of primary osteoarthritis or degenerative joint disease of the knee. Exclusion Criteria: * Patient has a Body Mass Index (BMI) \> 40. * Patient has been diagnosed with osteoporosis or displays poor bone quality per the discretion of the investigator. * Patient has an active or suspected latent infection in affected knee joint. Patient has neuromuscular or neurosensory deficiency. * Patient is diagnosed with systemic disease or metabolic disorder (e.g., Lupus, Charcot's. Paget's). * Subject is a woman who is pregnant or lactating. * Patient has a contralateral amputation. * Patient's affected knee has a flexion contracture greater than 15 degrees. * Patient has history of post operative arthrofibrosis. * Patient's affected knee has a partial knee arthroplasty. * Patient has undergone contralateral TKA within the last three months. * Patient is currently involved in any personal injury litigation, medical-legal, or worker's compensation claims. * Patient who is bedridden per the discretion of the investigator. * Patient has a medical condition with less than 2 years of life expectancy.