Evaluation of in vivo wear of vitamin E-diffused highly crosslinked polyethylene at five years

Abstract

Aims The primary aim of this study was to compare the wear properties of vitamin E-diffused, highly crosslinked polyethylene (VEPE) and one formulation of moderately crosslinked and mechanically annealed ultra-high molecular weight polyethylene (ModXLPE) in patients five years after primary total hip arthroplasty (THA). The secondary aim was to assess the clinical results of patients treated with VEPE by evaluating patient-reported outcome measures (PROMs), radiological evidence of fixation, and the incidence of mechanical failure. Patients and Methods A total of 208 patients (221 THAs) from four international centres were recruited into a prospective study involving radiostereometric analysis (RSA) and the assessment of clinical outcomes. A total of 193 hips (87%) were reviewed at the five-year follow-up. Of these, 136 (70%) received VEPE (vs ModXLPE) liners and 68 (35%) received ceramic (vs metal) femoral heads. PROMs and radiographs were collected preoperatively and at one, two, and five years postoperatively. In addition, RSA images were collected to measure PE wear postoperatively and at one, two, and five years after surgery. Results We observed similar bedding in one year postoperatively and wear two years postoperatively between the two types of liner. However, there was significantly more penetration of the femoral head in the ModXLPE cohort compared with the VEPE cohort five years postoperatively (p < 0.001). The only variables independently predictive of increased wear were ModXLPE (vs VEPE) liner type (β = 0.22, p = 0.010) and metal (vs ceramic) femoral head (β = 0.21, p = 0.013). There was no association between increased wear and the development of radiolucency (p = 0.866) or PROMs. No patient had evidence of osteolysis. Conclusion Five years postoperatively, patients with VEPE (vs ModXLPE) and ceramic (vs metal) femoral heads had decreased wear. The rates of wear for both liners were very low and have not led to any osteolysis or implant failure due to aseptic loosening.

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

“… 7 Our study did not include adequate numbers for analysis or antioxidant polyethylene. 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 …”

Model-Based Roentgen Stereophotogrammetric Analysis Using Elementary Geometrical Shape Models: Reliability of Migration Measurements for an Anatomically Shaped Femoral Stem Component

“…Classical marker-based RSA or mbRSA approach offers the opportunities: to measure in vivo implant fixation [43,44], to investigate, e.g., new THA design or coatings, degenerative changes [45][46][47], joint kinematics [48] and pathomechanism [49], and bony fusion [50]. Additionally, it offers the opportunity to investigate the effect of joint material connection within total joint arthroplasty, likewise the head-taper junction [17].…”

Recent update on crosslinked polyethylene in total hip arthroplasty

“…At this short term, vitamin E poly has not proved any clinically significant advantage in terms of patient function, wear or revision rate as compared to first generation of XLPE. Galea et al [18] published data from a multicenter study assessing the midterm behavior of a vitamin E infused XLPE. Implant survivorship was 97.1% at 5 years.…”