A Comparison Between Signature Total Knee Arthroplasty (TKA) to Conventional TKA and Computer Assisted TKA

The objective of this study is to report and compare on the outcomes from patients undergoing total knee arthroplasty utilizing 'SignatureTM Personalised Patient Care', Conventional Total Knee Arthroplasty and Computer Assisted Navigation.

The 'SignatureTM Personalised Patient Care' is a system that uses a patient's Magnetic Resonance Imaging (MRI) and X-ray design to build surgical instruments customized for a patient's unique knee anatomy. Cutting positioning guides are produced to match the outer shape of the individual's distal femur and proximal tibia.

The cutting positioning guides are intended to be used as patient-specific surgical instrumentation to assist in the positioning of total knee replacement components intra-operatively and in guiding the marking of bone before cutting.

Inclusion criteria

• Patient is of legal age and skeletally mature
• Patient requires primary total knee arthroplasty due to non- inflammatory degenerative joint disease (e.g. osteoarthritis, traumatic arthritis, a vascular necrosis, dysplasia/DDH) or inflammatory joint disease (e.g., Rheumatoid arthritis).
• Patient has met an acceptable preoperative medical clearance and is free from or treated for cardiac, pulmonary, haematological, etc., conditions that would pose excessive operative risk
• The patient will be available for follow up throughout the duration of the study.

Exclusion criteria

• Patient is unable to have an MRI scan due to the following conditions:

• Cardiac pacemaker
• Surgical clips in head (aneurysm clips)
• Some artificial heart valves
• Electronic inner ear implants
• Metal fragments in eyes
• Electronic stimulators
• Implanted pumps
• Patient has active infection or sepsis (treated or untreated)
• Patient has any vascular insufficiency, muscular atrophy, or neuromuscular disease severe enough to compromise implant stability or postoperative recovery.
• Patient is female of child-bearing age and not taking contraceptive precautions.
• Patient has inadequate bone stock to support the device (e.g. severe osteopenia, family history of severe osteoporosis or osteopenia).
• Patient has known moderate to severe renal insufficiency.
• Patient has a known or suspected metal sensitivity.
• Patient is immunosuppressed or receiving high doses of corticosteroids.
• Patient has an emotional or neurological condition that would pre-empt their ability or willingness to participate in the study including mental illness, mental retardation, or drug, alcohol abuse.
• Patient has BMI >40.