Unity Total Knee Replacement Using Two Different Surgical Techniques

Unity Total Knee Replacement: Prospective Single-centre Clinical Study

This study will compare two different surgical methods used in total knee replacement with the Unity Total Knee Replacement System. The study will evaluate these two methods based on patients' ability to perform various tasks prior to surgery and at 4 time points during the first 12 months after surgery.

This study will be conducted at a single centre. The study has two treatment groups. One group of 50 knees (approximately 50 subjects) will have a surgical method that uses mechanical alignment (alignment based on how the leg and knee joint move) to determine the proper position of the knee replacement device. The other group of 50 knees (approximately 50 subjects) will have a surgical method that uses anatomical alignment (alignment based on how the anatomy/structure of the leg and knee joint) determine the proper position of the knee replacement device. Subjects will be randomly assigned to one of the two groups. Clinical and functional tests will be conducted pre-operatively and at 6 weeks, 3 months, 6 months and 12 months to determine overall knee function. In addition, a CT scan will be completed pre-operatively and at 6 weeks to assess changes in alignment.

Inclusion Criteria:

• The patient must be listed for a primary total knee replacement using the Corin Unity Total Knee Replacement System, according to the product 'Instructions For Use'
• The patient must give signed informed consent to participate in the study
• The patient must be able to understand all that is expected of them and be able to comply with the study protocol
• Male and female patients who are skeletally mature

Exclusion Criteria:

• Any patient with a total knee replacement not implanted with a Corin Unity Total Knee Replacement
• Any patient with a revision total knee replacement or conversion of a Unicondylar replacement to a total knee replacement on the operative knee
• Any patient with fixed flexion contracture greater than 20 degrees
• Any patient with varus/valgus deformity greater than 15 degrees
• Any case not described in the inclusion criteria
• Any patient who cannot or will not provide signed informed consent for participation in the study
• Any patient whose prospects for a recovery to independent mobility would be compromised by known co-existent, medical problems
• Any patient with a known sensitivity to device material
• Any patient who is pregnant
• Any patient currently a prisoner
• Any patient known to be a drug or alcohol abuser, or have a psychological disorder that could affect follow-up care or treatment outcomes
• Any patient currently involved in any personal injury litigation, medical-legal or worker's compensations claims
• Any patient unable to read and understand English