Early Identification of Poorly Performing Implants in Michigan With the Example of the Vanguard XP

Background

Arthroplasty registries play a critical role in improving the quality of care and performing post-market surveillance of medical devices. We report the Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) findings specific to the Biomet Vanguard XP bicruciate-retaining total knee implant.

Methods

Data were collected from MARCQI’s 2019 report (February 15, 2012, through December 31, 2018). Demographic data were analyzed to determine differences between Vanguard XP and all other implants. The cumulative percent revision (CPR) was computed from the survival function, S(t), using CPR(t) = 100∗(1 − S(t)). A log-rank test was used to assess differences in the CPR curve for the Vanguard XP and all other implants.

Results

There were 148,832 knee arthroplasty cases in the MARCQI registry and 507 using Vanguard XP implant combinations. The unadjusted cumulative percent revision curve up to 5 years postoperatively for the Vanguard XP differed from all other implants (P < .0001). The hazard ratios for the 3 factors included in the Cox proportional hazards model were all significantly different from unity: implant (2.76, 95% CI: 1.98-3.86), sex (0.80, 95% CI: 0.74-0.85), and age (0.96, 95% CI: 0.96-0.97). The top 3 reasons for revision were pain, arthrofibrosis, and aseptic loosening. All surgeons who used the Vanguard XP experienced higher failure rates.

Conclusions

The Vanguard XP experienced higher early failure rates than other TKA implants within the MARCQI registry. The development of thresholds and benchmarks for registry reporting in collaboration with industry could potentially save patients from the morbidity caused by implants that do not perform as well as anticipated.