In January 2005, the oversight responsibility of the Post-Approval Studies Program was transferred to the Division of Epidemiology (DEPI) of the Office of Surveillance and Biometrics (OSB)/Center for Devices and Radiological Health (CDRH).
The CDRH Post-Approval Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated as a condition of approval of a premarket approval (PMA) application, protocol development product (PDP) application, or humanitarian device exemption (HDE) application. The program helps ensure that well-designed post-approval studies (PAS) are conducted effectively and efficiently and in the least burdensome manner.
CDRH has established an automated, internal tracking system that efficiently identifies the reporting status of active PAS studies ordered since January 1, 2005 based on study timelines incorporated in study protocols and agreed upon by the CDRH and applicants. This system represents CDRH's effort to ensure that all PAS commitments are fulfilled in a timely manner.
In addition, CDRH launched this publicly available webpage to keep all stakeholders informed of the progress of each PAS. The webpage displays general information regarding each PAS, as well as the overall study status (based on protocol-driven timelines and the adequacy of the data) and the applicant's reporting status for each submission due.
This is a prospective, multi-center, parallel group, controlled post-approval study comparing the clinical performance of
the LPS-Flex Mobile Bearing Knee with the LPS-Flex Fixed Bearing Knee. Group 1 consists of patients who received either the LPS-Flex Fixed Bearing Knee or the LPS-Flex Mobile Bearing Knee during the active IDE, completed the IDE study and have provided written consent to participate in the post-approval study. Group 2 patients will be enrolled into a single-arm, historically controlled, mid-term study (5 years) and this group will consist of those patients who receive the LPS-Flex Mobile Bearing Knee after the device approval.
Study Population Description
Study population is as per device indication. This device is indicated for patients with severe
knee pain and disability due to: - Rheumatoid arthritis (RA), osteoarthritis (OA), primary and secondary traumatic arthritis, polyarthritis. - Collagen disorders, and/or avascular necrosis of the femoral condyle or pseudo-gout - Post-traumatic loss of joint configuration, particularly when there is patellofemoral erosion, dysfunction or prior patellectomy.- Moderate valgus, varus, or flexion deformities.
The sample size is 400 patients. Group 1 will consist of approximately 300 patients already
implanted during the IDE study with either the LPS-Flex Fixed Bearing Knee (control population, N=150) or the LPS-Flex Mobile Bearing Knee device (N=150) at one of approximately 10 sites. Group 2 will consist of approximately 100 patients who are eligible for a total knee replacement, have chosen to receive the LPS-Flex Mobile Bearing Knee, and meet the PAS eligibility criteria.
A composite clinical success, defined by the following criteria, will be used as the primary
outcome: - Knee Society assessment score greater than/equal to 70 points- Knee Society function score greater than/equal to 70 points - No intended, actual, or planned removal of any component of the knee system - Absence of severe knee-related complications - An absence of subsidence of greater than or equal to 2 millimeters and an absence of both osteolysis and radiolucencies greater than or equal to 2 millimeters as determined by independent radiographic reviewer
Followup Visits and Length of Followup
The patients will be followed at 6 weeks, 6 months and at annual increments up
to 5 years post-operation for Group 2 and followed at 5, 6, 8 and 10 years post-operation for Group 1.