New Instrumentation Reduces Operative Time in Medial Unicompartmental Knee Arthroplasty Using the Oxford Mobile Bearing Design

Abstract

Redesigned instrumentation has become available for implantation of the Oxford Mobile Bearing Medial unicompartmental knee arthroplasty. To assess the benefit of these changes, we compared operative time of 200 Phase III and 176 Microplasty UKA done 2008-2011. An average time savings of 8.6 minutes was seen with the Microplasty design. Additionally, the standard deviation in operative times, minimum and maximum operatives were lower in knees in which Microplasty instrumentation was utilized. A 15% savings in operative time was seen with the new Microplasty instrumentation.

Supine Knee Positioning Does Not Interfere with Mobile-Bearing Unicompartmental Knee Arthroplasty Performance

“…Therefore, a p -value of < 0.05 allowed us to reject the null hypothesis and indicated equivalence (i.e., that the two positioning types are the same). Using extant research and clinical experience, d-values were prespecified for procedure time, 10 tibial and femoral alignment, 11 arc of motion, 12 laxity, 13 and fractures ( Table 1 ). For learning ability or time for individual steps of the cases, d-values were set to the smallest values for which resources were available to study an effect.…”

No difference in the use of revision components and rerevision rate in conversion to total knee replacement following Oxford Partial Knee Microplasty Instrumentation: a registry study of 529 conversions

“…The 3-year re-revision rates were 8.4% (CI 4. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] after conversion to TKR for failed Microplasty and 11% (CI 7. [8][9][10][11][12][13][14][15] for failed non-Microplasty instrumented PKRs with a hazard ratio of 0.77 (CI 0.36-1.7).…”

“…Microplasty instrumentation for the Oxford Mobile Partial Knee (Zimmer Biomet, Warsaw, IN, USA), was introduced as having a more consistent implant position and more accurate and bone -preserving tibial resection [8]. Recent results demonstrated improved implant position with reduced operation times using Microplasty instrumentation [9][10][11][12]. A recent group-matched registry study showed a 40% decrease in revision rate of PKRs instrumented with Microplasty (3.3% vs. 5.5%) [13].…”