Prospective Multicenter Post Approval Study of the LPS-Flex Mobile Bearing Knee

Inclusion Criteria: * Osteoarthritis * Primary and secondary traumatic arthritis * Avascular necrosis of the femoral condyle * Moderate varus, valgus, or flexion deformities (i.e. valgus/varus deformity of less than or equal to 15 degrees, fixed flexion deformity of less than or equal to 10 degrees) Exclusion Criteria: * Previous history of infection in the affected joint and/or local/systemic infection that may affect the prosthetic joint * Insufficient bone stock on femoral or tibial surfaces * Skeletal immaturity * Neuropathic arthropathy * Osteoporosis or any loss of musculature or neuromuscular disease that compromises the affected limb * A stable, painless arthrodesis in a satisfactory functional position * Severe instability secondary to the absence of collateral integrity * Total knee arthroplasty is contraindicated in patients who have rheumatoid arthritis (RA) and an ulcer of the skin or a history of recurrent breakdown of the skin because their risk of postoperative infection is greater. RA patient using steroids may also have increased risk of infection. Late infections in RA patients have been reported 24+ months postoperative. * Patient is a poor compliance risk, i.e., history of ethanol or drug abuse, or mental handicap that would compromise patient compliance with respect to rehabilitation or follow-up * Patient is not willing or able to give informed consent to participate in the follow-up program * Patient is not willing to return for all scheduled follow…