The primary objectives of this pilot clinical study include:

• Evaluate clinical outcomes and quality of life on patients who received Vanguard PS Total Knee in Korean population
• Evaluate safety of Vanguard PS Total Knee in Korean population

This study is a prospective, single cohort, multi-center study of Vanguard PS system and will be conducted in Korea with 2 institutions. The study will be conducted over a period of 10 years. Patients will be followed at immediate post-op, 6 weeks, 6 months and 1 year, 3 years.

Total of 2 sites will be involved in this study. 50 cases on each sites and total of 100 subjects will be enrolled in the study.

Primary end-point will be KSS at 1 year post op and secondary end-points are Survivorship of the product, KSS, EQ5D, High-Flexion Knee Score, Radiographic Assessment, and any kind of complication including lost to follow up.

Inclusion Criteria:

• Painful and disabled knee joint resulting from osteoarthritis, rheumatoid arthritis, traumatic arthritis, where one or more compartments are involved.
• Correction of varus, valgus, or posttraumatic deformity.
• Correction or revision of unsuccessful osteotomy, arthrodesis, or failure of previous joint replacement procedure
• Need to obtain pain relief and improve function
• Ability and willingness of the patient to follow instructions, including control of weight and activity level
• A good nutritional state of the patient, and
• The patient must have reached full skeletal maturity (at least 18 years old).

Exclusion Criteria:

• infection
• sepsis
• osteomyelitis
• Uncooperative patient or patient with neurologic disorders who are incapable of following directions
• Osteoporosis
• Metabolic disorders which may impair bone formation
• Osteomalacia
• 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, neuromuscular disease
• Incomplete or deficient soft tissue surrounding the knee

Total 100 cases

each site of 6 sites delegated to enroll 50 cases each