As an intraoperative tool, a modern robotic total knee arthroplasty (TKA) system should be able to identify a patient's native femoral and tibial anatomy, as well as, assess ligament tension and gap balance. The surgeon in real time is then able to develop and execute a patient specific plan in terms of component size, alignment and rotation. In our institution we have begun to use, the OMNIBotics Knee system (Corin), which utilizes an active motorized knee spacer, BalanceBot, to objectively measure ligament tension and gap balance after the tibia has been cut and its alignment confirmed. This information is then processed through the OMNIbotics computer algorithm to appropriately size, align, and rotate the femur component to balance the flexion and extension gaps. The purpose of this study is to perform a randomized pilot study looking for an effect on early functional outcomes comparing robotic assisted TKA (RATKA) versus conventional TKA technique.

Inclusion Criteria:

• All unilateral primary knee arthroplasties performed by the investigator participating in this study will be eligible for inclusion
• Diagnosis of primary osteoarthritis

Exclusion Criteria:

• Revision surgery
• Bilateral knee surgery
• Age <18 or >80
• BMI >40
• Baseline lower extremity strength less than 5/5
• History of chronic narcotic use, defined as more than 5mg of oxycodone q4 hours
• Functionally limiting spine disease
• Other functionally limiting lower extremity disorder (i.e. symptomatic ipsilateral hip disease)
• Patients who cannot perform the baseline functional tests
• Allergy/contraindication to protocol medications
• Post-traumatic arthritis
• Inflammatory arthritis
• Pregnancy
• Prisoners
• Patients receiving care as a result of a worker's compensable injury
• General anesthesia