Funding withdrawn, no participants recruited

In vivo knee kinematics will be assessed for 20 subjects that have been implanted with either a MicroPort Medial Pivot or DePuy Attune posterior cruciate retaining (PCR) total knee arthroplasty (TKA) by Dr. Russell Nevins of Nevada Orthopedic & Spine Center [this is the location from which participants will be recruited].

There will be ten subjects with the MicroPort implant and ten with the DePuy Attune implant; however, we will increase enrollment to 24 subjects (12 in each group) to ensure that researchers acquire the necessary 20 usable datasets for analysis and also to account for any subjects that may drop out of the study. All TKAs should be judged clinically successful based on the surgeon's evaluation and each patient's Forgotten Knee Score. Each subject should have a well-functioning prosthesis, be at least six months post-operative, and should have good-to-excellent post-operative passive flexion.

Inclusion Criteria:

• Subjects will have either a MicroPort Medial Pivot or DePuy Attune PCR TKA.
• Subjects must be at least six months post-operative.
• Participants must be judged clinically successful based on the surgeon's evaluation and their Forgotten Knee Score.
• Participants must be able to perform the required activities - stepping up and a deep knee bend.
• Subjects must be willing to sign the Informed Consent (IC) / HIPAA form to participate in the study

Exclusion Criteria:

• Pregnant, potentially pregnant or lactating females. To satisfy radiation protocol, each female subject will be asked if she is pregnant, or possibly could be pregnant. A pregnant person will not be allowed to participate in the study.
• Subjects without one of the two types of knee implants under investigation.
• Subjects who are unable to perform stepping up and deep knee bend.
• Subjects who are unwilling to sign Informed Consent/ HIPAA documents.
• Does not speak English.

There will be ten subjects with the MicroPort implant and ten with the DePuy Attune implant; however, we will increase enrollment to 24 subjects (12 in each group) to ensure that researchers acquire the necessary 20 usable datasets for analysis and also to account for any subjects that may drop out of the study. All TKAs should be judged clinically successful based on the surgeon's evaluation and each patient's Forgotten Knee Score. Each subject should have a well-functioning prosthesis, be at least six months post-operative, and should have good-to-excellent post-operative passive flexion

Researchers would like to retain this study data in our secure database so as to continue to add relevant, current data to our digital collection to help us work with manufacturers in the future to create better implants that last longer and will not require revision surgery. Participants will be asked if their study data may remain a part of the University of Tennessee's Center for Musculoskeletal Research data collection for use in future studies in the IC. Identifiers are automatically removed from the database upon entry into the secure server. Data shared with sponsors is de-identified.