A Clinical Investigation to evaluate the Apex KneeTM Pegged Tibial Baseplate Porous Coated components in primary Total Knee Arthroplasty using Roentgen Stereophotogrammetric Analysis (RSA)

This is a pre-market, multi-centre, prospective, open label study to evaluate the safety and performance of the Apex Knee™ Pegged Tibial Baseplate Porous Coated components used in combination with APEX Knee™ CR femoral component. The Apex Knee™ System is a Class III Orthopaedic device intended for use as a primary or revision Total Knee Replacement. It is approved by the Therapeutic Goods Administration and is listed on the prostheses list. The Apex Knee™ Pegged Baseplate is a line extension to the existing Apex Knee™ System and will serve as the tibial component of the primary total knee replacement in in this study. This study will be conducted under TGA Clinical Trial Notification Scheme (CTN) as the pegged baseplates are not yet approved for use in Australia. This clinical investigation aims to monitor the ongoing safety and performance of the Apex Knee™ Pegged Baseplate Porous Coated components following primary total knee arthroplasty. Roentgen Stereophotogrammetric Analysis (RSA) will be performed post-operatively to monitor fixation over time. In this study the eligible patients who will undergo primary total knee arthroplasty will be identified by the Orthopaedic surgeon from his patient database. The patients will be a given an information and consent form to read and sign. Following the signature, the patients will be assessed for suitability for participating in the study. Once they fit the criteria, they will be enrolled in the study. After enrolment the patients will complete some assessments and an X-ray. Medical History will be collected and physical health assessment will be done. They will also complete 3 quality-of-life questionnaires to assess their quality of life before the surgery. On the day of the surgery the participants will receive the investigational device, Apex Knee™ Pegged Porous Coated Cementless Baseplate for their knee surgery. The remaining components of the Apex Knee™ System remain unchanged. The participants will have the option to have this implanted only if they are eligible/choose to enrol in the study. The surgery will be completed by the Orthopaedic surgeons and will take about 2 hours. Before the surgery the surgeons will be trained on the surgical techniques. Before implanting the knee replacement, the surgeon will insert some very small metal beads (1mm in diameter, about 9 in total) into the bone surrounding the knee implant. These beads allow very accurate measurement of movement over time via a special X Ray technique called Roentgen Stereophotogrammetric X Ray (RSA). This will in turn help determine whether there are early signs of loosening or wear of your knee replacement Following the surgery, the patient will complete the RSA while at the hospital before discharge. The patient will complete a few follow up visits over a span of 2 years where the safety and performance of the Apex Knee™ Pegged Baseplate will be measured by various assessments such as RSA radiological assessments, physical exams, range of movements (ROMs) and the quality-of-life questionnaires. Time points include 6 weeks, 6 months, 12 months and 2 years. Some of these follow up visits will be completed at the Orthopaedic surgeon’s office and some of these visits can be completed from home where the patients will be completing the questionnaires via paper, on their smart phone or computer. Throughout the study any adverse event that the patient may be experiencing will be reported to the Orthopaedic surgeon and his study team. The follow up study visits will take approximately 1-2 hours depending on the nature of the visit. The study team will send timely reminders to the participant ahead of the follow up visit.