Persona TKA With iASSIST Knee System and iASSIST Knee System

Randomized Controlled Study Comparing iASSIST Knee System Versus Conventional Instrumentation

The purpose of this study is to compare the accuracy of knee component alignment between patients operated with iASSIST Knee (Investigational group) versus patients operated without iASSIST Knee (Control group) using the same implant system.

Objective： To compare the accuracy of knee component alignment between patients operated with iASSIST Knee (Investigational group) versus patients operated without iASSIST Knee (Control group) using the same implant system.

Endpoint： Primary： The alignment accuracy of the knee femoral and tibial components at 6 months for the investigational group compared to the control group.

Secondary：Health Status after TKA, Operating Room efficiency and Complication rate after TKA for the investigational group compared to the control group.

Inclusion Criteria:

In order to be eligible to participate in this study, a patient must meet all of the following criteria.

• Knee (either unilateral or bilateral) osteoarthritis (varus deformity only)
• Male or female
• At least 20 years of age
• Patients willing to return for follow-up evaluations.

Study Specific Requirements for Principal Investigator/Site

• Principal Investigator (PI) must have experience of at least 5 TKAs of iASSIST Knee with Persona and Persona conventional instrument system before any study specific activities.
• Site has sufficient resources to take limb CT scanning at 6 months follow-up visit.

Exclusion Criteria:

Absolute contraindications include:

• Knee degenerative diseases other than knee osteoarthritis (such as necrosis/rheumatoid arthritis)
• Too severe OA deformation (FTA: > 190 degrees/< 175 degrees)
• Active infection (or within 6 weeks after infection)
• Sepsis
• Osteomyelitis
• Any type of implant is inserted in the affected side of lower extremity
• Hip and/or foot disease on the affected side

Additional contraindications include:

• Uncooperative patient or patient with neurologic disorders who are incapable of following directions
• Diagnosed osteoporosis or osteomalacia
• Metabolic disorders which may impair bone formation
• Distant foci of infections which may spread to the implant site
• Rapid joint destruction, marked bone loss or bone resorption apparent on roentgenogram
• Vascular insufficiency, muscular atrophy or neuromuscular disease.