A systematic review of radiological outcomes of highly cross-linked polyethylene versus conventional polyethylene in total hip arthroplasty

403

282

Background Highly crosslinked polyethylene (HXLPE) was introduced to reduce wear and osteolysis in total joint arthroplasty. While many studies report wear and osteolysis associated with HXLPE, analytical techniques, clinical study design and followup, HXLPE formulation and implant design characteristics, and patient populations differ substantially among investigations, complicating a unified perspective. Questions/purposes Literature on first-generation HXLPE was summarized. We systematically reviewed the radiographic wear data and incidence of osteolysis for HXLPE in hip and knee arthroplasty. Methods PubMed identified 391 studies; 28 met inclusion criteria for a weighted-averages analysis of two-dimensional femoral head penetration rates. To determine the incidence of osteolysis, we estimated a pooled odds ratio using a random-effects model.Results Weighted-averages analyses of femoral head penetration rates in HXLPE liners and conventional UHMWPE liners resulted, respectively, in a mean twodimensional linear penetration rate of 0.042 mm/year based on 28 studies (n = 1503 hips) and 0.137 mm/year based on 18 studies (n = 695 hips). The pooled odds ratio for the risk of osteolysis in HXLPE versus conventional liners was 0.13 (95% confidence interval, 0.06-0.27) among studies with minimum 5-year followup. We identified two clinical studies of HXLPE in TKA, preventing systematic analysis of outcomes. Conclusions HXLPE liner studies consistently report lower femoral head penetration and an 87% lower risk of osteolysis. Reduction in femoral head penetration or osteolysis risk is not established for large-diameter ([ 32 mm) metallic femoral heads or ceramic femoral heads of any size. Few studies document the clinical performance of HXLPE in knees.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

History and Systematic Review of Wear and Osteolysis Outcomes for First-generation Highly Crosslinked Polyethylene

Kurtz

Gawel

Patel

2011

403

282

“…Highly crosslinked polyethylene (HXLPE) was introduced in the 1990s with the specific aim of reducing wear in total joint arthroplasty [12]. Within total hip arthroplasty (THA), HXLPE has demonstrated reduced radiological wear [12,13,17] and decreased risk of revision versus conventional polyethylene, which is defined as having been exposed only to a standard dose of gamma radiation during sterilization (at a dose of 25-40 kGy) [1-4, 20, 25]. For TKAs, the evidence is less clear regarding the beneficial effects of HXLPE over conventional polyethylene tibial liners.…”

Section: Introductionmentioning

confidence: 99%

Is There a Difference in Total Knee Arthroplasty Risk of Revision in Highly Crosslinked versus Conventional Polyethylene?

Paxton

Inacio

Kurtz

et al. 2015

Background Highly crosslinked polyethylene (HXLPE) was introduced to reduce wear and associated osteolysis in total knee arthroplasty (TKA). However, there is limited clinical evidence that HXLPE is more effective than conventional polyethylene (CPE) in TKA. Questions/purposes (1) Do primary TKAs with HXLPE tibial inserts have a lower risk of revision (all-cause, aseptic, and septic) than TKAs with CPE tibial inserts? (2) In NexGen TKA (Zimmer Inc, Warsaw, IN, USA) bearings, do HXLPE tibial inserts have a lower risk of revision (all-cause, aseptic, and septic) than CPE tibial inserts? (3) In Press-Fit Condylar TKA (PFC or PFC Sigma; DePuy Inc, Warsaw, IN, USA), do HXLPE tibial inserts have a lower risk of revision (all-cause, aseptic, and septic) than procedures performed with CPE tibial inserts? Methods The Kaiser Permanente Total Joint Replacement Registry was used to identify primary TKAs (N = 77,084) performed during the study period (April 2001 to December 2011) with cobalt-chromium alloy on CPE (CoCr-CPE) and CoCr-HXLPE bearings. The registry has 95% voluntary participation and less than 9% were loss to followup during the 10-year study period. A total of 60,841 (79%) had CoCr-CPE bearings, 11,048 (14%) had CoCr-HXLPE bearings, and 5195 (7%) were unknown. Specific knee implant designs (NexGen, Zimmer and PFC-Sigma, DePuy Inc) were also evaluated. These implants represented 41% (31,793) and 49% (37,457), respectively, of the 77,084 TKAs of known implant types registered during that period; implant selection was at the discretion of the attending surgeon. Descriptive statistics and marginal Cox regression models with propensity score adjustments were applied to compare risk of revision for CoCr-CPE versus CoCr-HXLPE TKA bearings. Results At 5 years followup, cumulative incidence of revision for CoCr-CPE and CoCr-XLPE were 2.7% and 3.1%, respectively. Adjusted risks of all-cause (hazard ratio [HR], 1.05; 95% confidence interval [CI], 0.86-1.29; p = 0.620), aseptic (HR, 1.01; 95% CI, 0.77-1.32; p = 0.954), and septic revision (HR, 1.11; 95% CI, 0.81-1.51; p = 0.519) did not differ in patients with CoCr-XLPE bearings compared with CoCr-CPE. Within TKAs with NexGen components, the adjusted risks of all-cause (HR, 1.14; 95% CI, 0.86-1.51; p = 0.354), aseptic (HR, 1.14; 95% CI, 0.79-1.65; p = 0.493), and septic revision (HR, 1.14; 95% CI, 0.76-1.73; p = 518) were similar in patients with CoCr-XLPE compared with those with CoCr-CPE bearings. Finally, within the TKAs with PFC components, the adjusted risks of all-cause (HR, 0.80; 95% CI, 0.49-1.30; p = 0.369), aseptic (HR, 0.62; 95% CI, 0.62-1.14; p = 0.123), and septic revision (HR, 0.97; 95% CI, 0.51-1.85; p = 0.929) were also similar in patients with CoCr-XLPE compared with those with CoCr-CPE bearings. Conclusions In this large study, we did not find differences in risk of revision for CoCr-HXLPE compared with CoCr-CPE bearings at 5 years followup. In selecting HXLPE in TKA, clinicians should consider the increased cost and lack of available evidence of ...

“…It is accepted that long-term survival of a THA is a multifactorial issue with the implant, the diagnosis, the patient, the surgeon, and surgical technique being equally important. Wear debris production from the bearing surfaces leads to the development of interface osteolysis, which, these days, is thought to be the main factor limiting longterm survival of the artificial joint [8,30]. Alternative bearing surfaces have thus been developed to reduce the amount of wear particles produced [8,30].…”

Section: Introductionmentioning

confidence: 99%

“…Polyethylene, moreover, has undergone many improvements, from the development of ultrahigh-molecular-weight (CPE) to crosslinked (XLPE) polyethylene. These improved polyethylenes have shown better wear characteristics in combination with mainly metallic heads in vitro [31,32,38] and in vivo [4,8,14,26,30].…”

Section: Introductionmentioning

confidence: 99%

Oxidized Zirconium Head on Crosslinked Polyethylene Liner in Total Hip Arthroplasty: A 7- to 12-year In Vivo Comparative Wear Study

Karidakis

Karachalios

2015

Background Osteolysis resulting from wear debris production from the bearing surfaces is a major factor limiting long-term survival of hip implants. Oxidized zirconium head on crosslinked polyethylene (XLPE) is a modern bearing coupling. However, midterm in vivo wear data of this coupling are not known. Questions/purposes The purpose of this study was to investigate in vivo whether the combination of an oxidized zirconium femoral head on XLPE produces less wear than a ceramic head on XLPE or a ceramic head on conventional polyethylene (CPE) couplings and whether any of these bearing combinations results in higher hip scores. Methods Between 2003 and 2007, we performed 356 total hip arthroplasties in 288 patients; of those, 199 (69.1%) patients (199 hips) were enrolled in what began as a randomized trial. Unfortunately, after the 57 th patient, the randomization process was halted because of patients' preference for the oxidized zirconium bearing instead of the ceramic after (as they were informed by the consent form), and after that, alternate allocation to the study groups was performed. Hips were allocated into four groups: in Group A, a 28-mm ceramic head on CPE was used; in Group B, a 28-mm ceramic head on XLPE; in Group C, a 28-mm Oxinium head on XLPE; and in Group D, a 32-mm Oxinium head on XLPE. The authors prospectively collected in vivo wear data (linear wear, linear wear rate, volumetric wear, and volumetric wear rate) using PolyWare software. Preoperative and postoperative clinical data, including Harris and Oxford hip scores, were also collected at regular intervals. Of those patients enrolled, 188 (95%) were available for final followup at a minimum of 7 years (mean, 9 years; range, 7-12 years). Results All bearing surfaces showed a varying high bedding-in effect (plastic deformation of the liner) up to the second postoperative year. At 5 years both oxidized zirconium on XLPE groups showed lower (p \ 0.01) volumetric wear (mean ± SD mm 3 ) and volumetric wear rates (mean ± SD mm 3 /year) ( Res (2015) 473:3836-3845 DOI 10.1007 Clinical Orthopaedics and Related Research ® A Publication of The Association of Bone and Joint Surgeons® (Group C: 356 ± 64 to 215 ± 54 mm 3 /year, Group D: 354 ± 50 to 210 ± 64 mm 3 /year) when compared with ceramic on CPE (Group A: 895 ± 131 to 380 ± 80 mm 3 /year) and ceramic on XLPE (Group B: 1625 ± 253 to 480 ± 101 mm 3 /year) groups. When wear rates of both oxidized zirconium groups were compared, no differences were found at any time interval with the numbers available. Two hips (one from Group A and one from Group B) are scheduled for revision as a result of wear and osteolysis. There were no differences in hip scores among the groups with the numbers available. Conclusions In this study, in vivo wear parameters were lower when the combination of an oxidized zirconium head on XLPE liner was used at an average of 9 years (range, 7-12 years) followup. Further larger-scale clinical studies should confirm these findings and evaluate osteolysis and revision rates...