Zimmer CAS PSI X-Ray Knee in TKA (Total Knee Arthroplasty)

Inclusion Criteria: * Male or female * Needs a primary TKA and he/she is Persona® knee implant compatible * Diagnosed with non-inflammatory degenerative joint disease (e.g., osteoarthritis, post-traumatic arthritis, avascular necrosis, etc.) * Over 18 years old * Able to: * Understand what participation in the study entails and willing to consent (patient or his/her legal guardian) to participate in the study by signing and dating an IRB/EC approved inform consent form. and * Follow surgeon/staff instructions, and * Return for all follow-up evaluations, and * Able and willing to undergo a preoperative radiographs (all cases) * Meets an acceptable preoperative medical clearance and is free of or treated for cardiac, pulmonary, hematological or other conditions that would pose excessive operative risk. * Has a presence of varus or valgus deformity of 15 degrees or less. Exclusion Criteria: * Is currently enrolled in an investigational new drug or device study * Has an active infection (including septic knee, distant infection, or osteomyelitis) * Has neurological disorders (including, but not limited to Parkinson's disease) * Has had a prior ipsilateral unicompartmental knee arthroplasty, TKA, knee fusion or patellectomy. * Has hip or knee ankylosis. * Have indications of intra- and/or extra-articular deformations that would eliminate or tend to eliminate adequate implant support or prevent the use of an appropriately sized implant, such as polio, history of tibial plateau fracture, etc. * Has any metal within 150 mm of the joint line for the operative-side knee. * Has knee deformities greater than 15 degrees of fixed varus, valgus, or flexion contracture on initial physical examination. * Is a female who is pregnant or lactating * Is currently involvement in any personal injury litigation, medical-legal or worker's compensation claims * Has arterial disease or stents that would exclude the use of a tourniquet. * Has insufficient quality or quantity of bone to support the implant due to prior knee surgery (or surgeries), cancer, metabolic bone disease, osteoporosis/osteopnea (diagnosed or treated with medication), active/old/remote infection, etc. * Has a mental condition that may interfere with his/her ability to give an informed consent or interfere with his/her ability or willingness to fulfill the requirements of the study. * Has a condition that would place excessive demands on the implant (e.g., Charcot's joints, muscle deficiencies, multiple joint disabilities, skeletal immaturity, etc.). * Has collateral ligament insufficiency. * Has an immunosuppressive disorder (e.g., AIDS, etc.) that would require cytotoxic drugs, corticosteroids, large dose of irradiation, or antilymphocytic serum.