Comparison of a Metal Backed Fixed-Bearing Tibial Baseplate and an All-Polyethylene Tibia in Total Knee Arthroplasty

Minneapolis Veterans Affairs Health Care System (VAHCS)

Status: Terminated

Conditions: Osteoarthritis, Knee

Treatments: Device: P.F.C.® Sigma Knee System; Procedure: TKA surgery with modular polished tibial baseplate/XLK design; Procedure: TKA surgery with the nonmodular APT/GVF design

Study type: Interventional

Funder types: Other U.S. Federal agency; Industry

Identifiers

NCT00979147

MVA-3946B

Details and patient eligibility

About

This study is designed to compare prospectively, in a randomized Level 1 evidence fashion, the clinical, functional, and radiographic results of a modular polished tibial (MPT) tray with a moderately cross-linked polyethylene (XLK) insert to an all-polyethylene tibial (APT) design with GVF polyethylene. Comparing these two designs will afford us information in the following areas:

1. Does a MPT/XLK design have improved wear characteristics over a nonmodular APT/GVF design?
2. Is there a clear clinical advantage to the MPT/XLK design in certain patient populations that justify its use over the APT/GVF design?

Answering these questions will allow surgeons to use both designs appropriately in different demand populations.

This study is designed to address the questions of whether an MPT/XLK design offers improvement in wear characteristics, Knee Society scores, KOOS, WOMAC, SF-36, or radiographic measures, over an APT design. The investigator's primary hypothesis is that there will be no difference in these outcome measures at a minimum two year follow-up. A secondary hypothesis based on the long-term follow-up of this group, up to twenty years, is that there will be no difference in implant survival.

Full description

Summary is detailed

Enrollment: 400 patients

Sex: All

Ages: 60 to 85 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• generally accepted clinical and radiographic criteria for total knee arthroplasty

Exclusion criteria

• Significant angular or bony deformity necessitating structural bone grafting or more extensive modular designs will be excluded at the discretion of the principle investigator
• Routine contraindications to TKA (active sepsis, Charcot arthropathy)
• Patients whose mental function preclude them from responding to our standard questionnaires

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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400 participants in 2 patient groups

Modular Metal Tibial Baseplate

Experimental group

Description:

Patients who were randomized to receive the modular polished tibial baseplate/XLK TKA

Treatment:

Procedure: TKA surgery with modular polished tibial baseplate/XLK design

Device: P.F.C.® Sigma Knee System

Device: P.F.C.® Sigma Knee System

All Polyethylene Tibial Baseplate

Active Comparator group

Description:

Patients who were randomized to receive the nonmodular APT/GVF TKA design.

Treatment:

Procedure: TKA surgery with the nonmodular APT/GVF design

Device: P.F.C.® Sigma Knee System

Device: P.F.C.® Sigma Knee System