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Purpose Concerns remain about potential increased wear with dual mobility cups related to the multiple articulations involved in this specific design of implant. This finite element analysis study aimed to compare polyethylene (PE) wear between dual mobility cup and conventional acetabular component, and between the use of conventional ultra-high molecular weight PE (UHMWPE) and highly cross-linked PE (XPLE)., Methods Patient-specific finite element modeling was developed for 15 patients undergoing primary total hip arthroplasty (THA). Five acetabular components were 3D modeled and compared in THA constructs replicating existing implants: a dual mobility cup with a 22.2-mm-diameter femoral head against UHMWPE or XLPE (DM22PE or DM22XL), a conventional cup with a 22.2-mm-diameter femoral head against UHMWPE (SD22PE) and a conventional cup with a 32-mm-diameter femoral head against UHMWPE or XLPE (SD32PE or SD32XL)., Results DM22PE produced 4.6 times and 5.1 times more volumetric wear than SD32XL and DM22XL (p < 0.0001, Cohen's d = 6.97 and 7.11; respectively). However, even if significant, the differences in volumetric wear between DM22XL and SD32XL as well as between DM22PE and SD22PE or SD32PE were small according to their effect size (p < 0.0001, Cohen's vertical bar d vertical bar= 0.48 to 0.65) and could be therefore considered as clinically negligible., Conclusion When using XLPE instead of UHMWPE, dual mobility cup with a 22.2-mm-diameter femoral head produced a similar amount of volumetric wear than conventional acetabular component with a 32-mm-diameter femoral head against XLPE. Therefore, XLPE is advocated in dual mobility cup to improve its wear performance.

Highly cross-linked ultrahigh molecular weight polyethylene (UHMWPE) was introduced to decrease wear debris and osteolysis. During cross-linking, free radicals are formed, making highly cross-linked polyethylene vulnerable to oxidative degradation. In order to reduce this process, anti-oxidant vitamin E can be incorporated in polyethylene. This review provides an overview of the effects of vitamin E incorporation on major complications in total joint arthroplasty: material failure due to oxidative degradation, wear debris and subsequent periprosthetic osteolysis, and prosthetic joint infections. Secondly, this review summarizes the first clinical results of total hip and knee arthroplasties with vitamin E incorporated highly cross-linked polyethylene. Based on in vitro studies, incorporation of vitamin E in polyethylene provides good oxidative protection and preserves low wear rates. Incorporation of vitamin E may have the beneficial effect of reduced inflammatory response to its wear particles. Some microorganisms showed reduced adherence to vitamin E-incorporated UHMWPE; however, clinical relevance is doubtful. Short-term clinical studies of total hip and knee arthroplasties with vitamin E-incorporated highly cross-linked UHMWPE reported good clinical results and wear rates similar to highly cross-linked UHMWPE without vitamin E.

Highly cross-linked ultrahigh molecular weight polyethylene (UHMWPE) was introduced to decrease wear debris and osteolysis. During cross-linking, free radicals are formed, making highly cross-linked polyethylene vulnerable to oxidative degradation. In order to reduce this process, anti-oxidant vitamin E can be incorporated in polyethylene. This review provides an overview of the effects of vitamin E incorporation on major complications in total joint arthroplasty: material failure due to oxidative degradation, wear debris and subsequent periprosthetic osteolysis, and prosthetic joint infections. Secondly, this review summarizes the first clinical results of total hip and knee arthroplasties with vitamin E incorporated highly cross-linked polyethylene. Based on in vitro studies, incorporation of vitamin E in polyethylene provides good oxidative protection and preserves low wear rates. Incorporation of vitamin E may have the beneficial effect of reduced inflammatory response to its wear particles. Some microorganisms showed reduced adherence to vitamin E-incorporated UHMWPE; however, clinical relevance is doubtful. Short-term clinical studies of total hip and knee arthroplasties with vitamin E-incorporated highly cross-linked UHMWPE reported good clinical results and wear rates similar to highly cross-linked UHMWPE without vitamin E.