RSA of the ATTUNE Knee System: RCT Comparing Traditional Vs Enhanced-Fixation Device Designs

This is a multi-centre, randomized controlled trial of patients undergoing posterior-stabilized total knee arthroplasty. In this study, the investigators propose to randomize 50 subjects to receive either the standard Attune PS TKA (n=25) or the enhanced fixation Attune S+ PS TKA (n=25) and follow them for a period of 2 years post-operatively. The primary outcome of the study will be stability of fixation of the tibial baseplate as measured by model-based RSA. Secondary outcomes will be to determine the functionality of patients after surgery using self-reported questionnaires.

• ATTUNE PS Knee (Device): The ATTUNE PS Knee is the standard implants.
• ATTUNE S+ PS Knee (Device): The ATTUNE S+ PS Knee is the enhanced fixation.

Primary outcomes

• RSA Migration [2 Years]: Migration of the tibial and femoral components between the 2 device designs.

Secondary outcomes

• Knee Replacement Expectation Survey (KRES) [Preoperative]: The KRES is a patient reported questionnaire that consists of 19 questions. The questions ask how each expectation is important in the treatment of the knee. The scale is rated: 1 (Very important) to 5 (This does not apply to me). The score ranges from 19 to 95 with higher scores associated with higher expectations.
• European Quality of Life (EQ-5D-5L) [Preoperative, 6 Weeks, 3 Months, 6 Months, 1 Year and 2 Years]: Evaluate and compare the change from preoperative to 2 years between the study groups timepoints in functional outcomes assessments. The EuroQol 5D 5L questionnaire is a standardized instrument for use as a measure of health outcome that is designed for completion by the subject.
• Pain score [Preoperative, 6 Weeks, 3 Months, 6 Months, 1 Year and 2 Years]: Evaluate and compare the change from preoperative to 2 years between the study groups timepoints in patient reported satisfaction as measured using the visual analogue scale (VAS) from 0 (No pain) - 100 (Worst pain imaginable)
• Patient satisfaction [Preoperative, 6 Months, 1 Year and 2 Years]: Evaluate and compare the change from preoperative to 2 years between the study groups timepoints in patient reported pain severity as measured using the visual analogue scale (VAS) from 0 (Unsatisfied) - 100 (Completely satisfied)
• Oxford 12 Knee [Preoperative, 6 Weeks, 3 Months, 6 Months, 1 Year and 2 Years]: Evaluate and compare the change from preoperative to 2 years between the study groups timepoints in functional outcomes assessments, patient reported outcome
• University of California at Los Angeles (UCLA) Activity Level scale [Preoperative, 6 Months, 1 Year and 2 Years]]: Evaluate and compare the change in UCLA activity score compared to baseline in the study cohort. UCLA activity scores range from 1 to 10, and is a measure of activity with 10 being most active.
• Pain Catastrophizing Scale (PCS) [Preoperative and 1 Year]: The patient are asked to indicate the degree to which they have the above thoughts and feelings when they are experiencing pain. Each PCS item is rated on a 5-point scale: 0 (not at all) to 4 (all the time). The PCS total score is computed by summing responses to the 13 items. PCS total scores range from 0 - 52.
• Pre-operative Patient's Knee Implant Performance (PKIP) [Preoperative, 6 Months, 1 Year and 2 Years]: The Pre-surgical and/or Post-surgical Patient's Knee Implant Performance (PKIP) questionnaire is a patient reported questionnaire that consists of 24 questions relating to the patient's awareness of their knee. Questions include the patient's self-confidence about the current status of their knee performance, stability, and overall satisfaction. Each question has a 5, 6 or 10 Likaert- like response option.
• Patient complications [Preoperative, 1 Week, 6 Weeks, 3 Months, 6 Months, 1 Year and 2 Years]: Evaluate the type and frequency of the complications/adverse events.

Sex: All, ages: 21 Years to 80 Years, accepts healthy volunteers

Inclusion Criteria:

* Symptomatic osteoarthritis of the knee indicating primary total knee arthroplasty
* Between the ages of 21 and 80 inclusive
* Patients willing and able to comply with follow-up requirements and self-evaluations
* Ability to give informed consent

Exclusion Criteria:

* Active or prior infection
* Medical condition precluding major surgery

• Thomas Turgeon, MD MPH FRCSC, Principal investigator, University of Manitoba
• Glen Richardson, MD MSc FRCSC, Principal investigator, Dalhousie University
• Douglas Naudie, MD FRCSC, Principal investigator, London Health Sciences Centre