The purpose of this evaluation is to evaluate the intraoperative soft tissue balance as assessed by the Orthosensor device, to measure the perioperative gait and function with the Muvr tracking device, and to correlate this soft tissue balance with early functional outcomes in the Persona total knee system.

This is a single surgeon, prospective, controlled study consisting of 50 patients with a primary indication of OA who are eligible for primary total knee arthroplasty using the Persona total knee system.

The patients are equally divided in two groups; patients in group 1 will receive traditional, manual soft-tissue balancing during surgery. For the purpose of the study, the balance will be quantitatively assessed at the end of the case, by means of surgeon-blinded VERASENSE measurements before and after cementation. For the patients in Group 2, intra-operative sensor feedback will be used in creating a quantitatively balanced knee (VERASENSE, OrthoSensor Inc.). Thereby, a quantitatively balanced knee is characterized by a mediolateral load differential below 15lbs at 10-45-90 degrees of flexion.

Post-operatively, the patients will be evaluated using the Muvr device at the day of surgery, day of discharge and 2, 6, and 12 weeks, and 1 year postoperatively. This device will provide quantitative feedback on different gait metrics as well as function during activities of daily living such as stair climbing / stair descent, walking, and timed get up and go testing.

During each post-operative visit, the following metrics will be recorded:

• Active and passive range of motion
• Implant alignment
• Patient reported outcomes by means of Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Forgotten Joint Score (FJS)

Inclusion Criteria:

1. Patient has a primary indication of osteoarthritis and is eligible for primary total knee arthroplasty using the Persona total knee system
2. Patient is willing and able to provide written Informed Consent prior to study surgery
3. Patient is willing and able to complete scheduled study procedures and follow-up evaluations as described in the Informed Consent Form

Exclusion Criteria:

1. Patient does not have a primary indication of osteoarthritis
2. Patient does not have access to internet or mobile device or understand how to use phone/app
3. Patient is not eligible or will not receive the Persona total knee system
4. Patient has not provided written Informed Consent

Healthy individuals having elective primary knee replacement