Catastrophic Failure of Regenerex Tibial Components: A Case Series

The aim of this study was to analyze short-term metal failures in well-placed Signature-guided Regenerex (Zimmer Biomet, Warsaw, IN) tibial components in a limited patient series. A retrospective, consecutive, nonrandomized, unblinded study from a limited cohort of young active osteoarthritis patients was conducted. All cases received a Regenerex tibial component which we evaluated for metal failure. Patients met the then current indications from the Center for Medicare and Medicaid Services Guidelines for knee replacement. Age, body mass index (BMI),and gender were compared between Regenerex and concurrent non-Regenerex knee arthroplasties. We identified a 4.7% (2 of 43) fracture rate in our Regenerex tibia replacements. Fractures occurred after 17 and 37 months, with a mean follow-up of 65 months (44-77). No statistical difference was seen in age or BMI between the fracture and nonfracture groups. Regenerex compared with standard arthroplasty patients were younger and predominantly male. Our inability to identify our fractures in the Food and Drug Administration (FDA) reporting site is concerning, suggesting additional cases may be unreported. A short-term Regenerex tibial fracture rate of 4.7% is unacceptably high. Inability to identify our fractures on the FDA Web site is a system failure, suggesting additional component fractures may be unreported.