Early aseptic loosening with a precoated low-profile tibial component: a case series

Between March 2007 and December 2008, we performed 529 consecutive total knee arthroplasties in 460 patients with the Zimmer (Warsaw, IN) NexGen MIS Tibial Component using a minimally invasive approach. Eight knees in 8 patients (1.5%) were revised for early aseptic loosening of the tibial component despite normal initial postoperative radiographs. Several additional patients have concerning radiographic signs of pending failure. The mean time to revision was 17 months (range, 9-31 months). Intraoperatively, in all cases, more than 50% of the tibial tray was devoid of cement and factory-applied polymethylmethacrylate. Our experience with early aseptic loosening of this tibial component has led us to discontinue its use until the etiology of the high early failure rate is able to be determined.