The objective of the observational study is to assess the positioning of customized guides designed from patients X-Rays (Zimmer® X-Ray PSI Knee) using optical navigation in primary total knee arthroplasty.

The proposed research is a single center, prospective, case series, and non-controlled study. One orthopedic surgeon will perform 30 primary TKAs using X-Ray PSI Knee guides, generated from X-ray. Patients who have been appropriately indicated as candidates for TKA and who meet the specified inclusion and exclusion criteria, will be informed about Zimmer® X-Ray PSI Knee technology and offered entry into the study. Informed consent, in accordance with current ethical board regulatory requirements and best practice, will be obtained from all patients.

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.

Patients over 18 years old with indication of Total Knee Arhtroplasty