Is There a Benefit to Highly Crosslinked Polyethylene in Posterior-stabilized Total Knee Arthroplasty? A Randomized Trial

Abstract

Background Polyethylene wear and osteolysis remain a concern with the use of modular, fixed-bearing total knee arthroplasty (TKA). A variety of highly crosslinked polyethylenes (XLPs) have been introduced to address this problem, but there are few data on the results and complications of this polyethylene in posterior-stabilized knee prostheses. Questions/purposes In a randomized prospective study design comparing standard polyethylene (SP) tibial inserts with XLP inserts, we asked the following questions: (1) Are there any differences in the clinical results (as measured by the classic Knee Society scoring system) and radiographic results (as measured by an evaluation for radiolucencies and osteolysis) between these groups? (2) What is the frequency of reoperation in these two groups? (3) Are there any specific complications related to XLP liners?Methods These are preliminary data from a single surgeon of a planned interim analysis of a prospective randomized study of one modular posterior-stabilized TKA. One hundred ninety-two patients (236 knees) were randomized to receive a SP compression-molded liner or a XLP (6.5 CGy electron beam-irradiated and remelted) polyethylene liner. There was no difference in the number of knees who were lost or refused followup (14 knees . There were no differences, with the numbers available, in the presence of effusion (two of 94 XLP and five of 99 SP) with 2 years minimum followup. There were no differences in the frequency of radiolucent lines (13 knees with SP and 15 with XLP) or of osteolysis (two knees with SP and none with XLP). There was no difference in frequency of reoperation between the two groups (three infections in 110 knees allocated to the XLP group and five (two infections, one femoral loosening, one instability, one fracture plating) in

Cross-linked versus conventional polyethylene for total knee arthroplasty: a meta-analysis

“…Zimmer) 2 years 0 CP 113 71.1 ± 7.3 20/93 NS Net-shape molding of GUR 1050 resin and sterilized by gamma radiation in nitrogen at a dose of 37 kGy. 0 Lachiewicz and Soileau 2015 [ 19 ] RCT XLPE 110 68 ± 10 35/75 31 Electron beam, 6.5 CGy irradiated in nitrogen, remelted to quench the free radicals; then sterilized by ethylene oxide Zimmer, Inc, Warsaw, IN, USA Minimum 2 years 14 CP 122 70 ± 10 37/85 31 Gamma-irradiated in nitrogen 21 Meneghini et al 2015 [ 20 ] PCT XLPE 64 63.8 18/29 31.5 GUR 1020 UHMWPE and cross-linking was performed with a cycled process of gamma-irradiation at 30 kGy followed by annealing at 130 °C for 8 h, which was repeated 3 times sequentially Posterior-substituting single-radius design (Triathlon; Stryker, Mahwah, NJ) 5.2 years (range, 4.3–5.8 years). 10 CP 50 67.3 12/25 31.1 Compression-molded GU 1020 UHMWPE, packed in nitrogen and gamma-irradiated at 30 kGy.…”

Influence of conformity on the wear of total knee replacement: An experimental study

“…Experimental studies have indicated improved wear performance compared with conventional UHMWPE, [8][9][10] and clinical studies have indicated a comparable or improved performance. 4,11 However, a trade-off between wear resistance associated with the level of cross-linking, and the mechanical properties of the material has been highlighted. 12,13 Asano et al 14 demonstrated an almost linear relationship between wear resistance and radiation dose, highlighting a corresponding reduction in mechanical properties.…”

Polyethylene in total knee arthroplasty: Where are we now?

“…55 Totally, six studies (three randomized clinical trials and three non-randomized clinical trials) were included with a follow-up period of 2-6 years (Table 3). [56][57][58][59][60]64 Outcome measures included total number of operations, reoperations for prosthesis loosening, radiolucent lines, osteolysis, prosthesis loosening, mechanical failures related to tibial PE, postoperative total knee score, and functional scores. No significant differences were seen in any of the measured variables.…”