A randomized double-blind noninferiority trial, evaluating migration of a cemented vitamin E-stabilized highly crosslinked component compared with a standard polyethylene component in reverse hybrid total hip arthroplasty

Abstract

Aims Radiostereometric analysis (RSA) studies of vitamin E-doped, highly crosslinked polyethylene (VEPE) liners show low head penetration rates in cementless acetabular components. There is, however, currently no data on cemented VEPE acetabular components in total hip arthroplasty (THA). The aim of this study was to evaluate the safety of a new cemented VEPE component, compared with a conventional polyethylene (PE) component regarding migration, head penetration, and clinical results. Patients and Methods We enrolled 42 patients (21 male, 21 female) with osteoarthritis and a mean age of 67 years (sd 5), in a double-blinded, noninferiority, randomized controlled trial. The subjects were randomized in a 1:1 ratio to receive a reverse hybrid THA with a cemented component of either argon-gas gamma-sterilized PE component (controls) or VEPE, with identical geometry. The primary endpoint was proximal implant migration of the component at two years postoperatively measured with RSA. Secondary endpoints included total migration of the component, penetration of the femoral head into the component, and patient-reported outcome measurements. Results In total, 19 control implants and 18 implants in the VEPE group were analyzed for the primary endpoint. We found a continuous proximal migration of the component in the VEPE group that was significantly higher with a difference at two years of a mean 0.21 mm (95% confidence interval (CI) 0.05 to 0.37; p = 0.013). The total migration was also significantly higher in the VEPE group, but femoral head penetration was lower. We found no difference in clinical outcomes between the groups. Conclusion At two years, this cemented VEPE component, although having a low head penetration and excellent clinical results, failed to meet noninferiority compared with the conventional implant by a proximal migration above the proposed safety threshold of RSA. The early proximal migration pattern of the VEPE component is a reason for continued monitoring, although a specific threshold for proximal migration and risk for later failure cannot be defined and needs further study. Cite this article: Bone Joint J 2019;101-B:1192–1198

Vitamin E-doped total hip arthroplasty liners show similar head penetration to highly cross-linked polyethylene at five years: a multi-arm randomized controlled trial

“…Five other RCT shave compared vE-PE and XLPE liner wear. 16 - 20 Two trials report no difference at two or seven years, respectively, while three trials report lower wear in vE-PE liners at five, five, and seven years, respectively. All these studies use the same RSA setup as this study.…”

“… 13 This material has shown increased resistance to oxidation and fatigue crack propagation, as well as a low wear rate in experimental settings and has been investigated in vivo. 14 - 20 …”

A higher degree of polyethylene irradiation is associated with a reduced risk of revision for aseptic loosening in total hip arthroplasties using cemented acetabular components

“…Promising results by clinical trials in uncemented cups 18 , 19 and some concerns in cemented cups suggest that registry monitoring will be key for these components in the future. 20 …”

Implant survival of 2,723 vitamin E-infused highly crosslinked polyethylene liners in total hip arthroplasty: data from the Finnish Arthroplasty Register

“…Since vitamin E-infused highly crosslinked polyethylene (VEPE) is a quite recent invention, there are only short-and mid-term data available on its efficacy and safety. Significantly lower femoral head penetration rates have been reported for VEPE liners by many authors in randomized controlled trials (RCTs) with radiostereometric analysis (RSA) compared with HXLPE liners (Nebergall et al 2017, Scemama et al 2017, Shareghi et al 2017, Galea et al 2018, Rochcongar et al 2018, Sköldenberg et al 2019. However, there is still a lack of real-world data from arthroplasty registers on the survival of VEPE liners.…”