Balanced Knee System Clinical Protocol for IRB Approval

Inclusion Criteria: * Loss of joint configuration and joint function. * Osteoarthritis of the knee joint. * Rheumatoid arthritis of the knee joint. * Post-traumatic arthritis of the knee joint. * Moderate valgus, varus, or flexion deformities. Exclusion Criteria: * Any patient not experiencing a compromised quality of life by loss of joint function and/or joint configuration, or pain from arthritis disease. * Any patient whose knee cannot be returned to normal function and normal stability through reconstructive procedures, including ligamentous balancing. * Active infection in or near the knee joint, fever and/or local inflammation signs, and elevation of sedimentation rate unexplained by other diseases should not be treated unless preoperative infection is ruled out. * Distant foci of infection, such as genitourinary, pulmonary, skin (chronic lesions or ulcerations), and other sites, which may result in hematogenous spread to the implant site. * Rapid joint destruction or bone absorption apparent on roentgenograms. * Neuromuscular disorders in which the potentially adverse effects on prosthesis function are not outweighed by the benefits gained by the patient from usage of the prosthesis. * Mental disorders which would compromise essential patient post-operative care. * A painless, stable arthrodesis in a functional position. * Allergic reactions to implant materials, and/or tissue reactions to the products of corrosion or wear. * Skeletal immaturity. * Any patient who is unwilling or unable to comply with post-operative instructions or clinical study requirements.