title: Cross-linked versus conventional polyethylene for total knee arthroplasty: a meta-analysis.
abstract: BACKGROUND
  Highly cross-linked polyethylene (HXLPE) has been reported as an effective material for decreasing polyethylene wear and osteolysis in total knee arthroplasty (TKA). Because no single study to date has been large enough to definitively determine the benefit of HXLPE in TKA, we conducted a meta-analysis to pool the results from randomized controlled trials (RCTs) and non-RCTs to make such a determination.
  
  
  METHODS
  Potential candidate articles were identified by searching the Cochrane Library, Medline (1966-2015.10), PubMed (1966-2015.10), Embase (1980-2015.10), ScienceDirect (1985-2015.10), and other databases. "Gray studies" were identified from the included articles' reference lists. Pooled data were analyzed using RevMan 5.1.
  
  
  RESULTS
  Three RCTs and three non-RCTs were included in the meta-analysis. There were no significant differences between the groups in the total number of reoperations (P = 0.11), reoperations for prosthesis loosening (P = 0.08), radiolucent line (P = 0.20), osteolysis (P = 0.38), prosthesis loosening (P = 0.10), and mechanical failures related to the tibial polyethylene (P = 1.00). Similarly, no significant differences between the two groups were found in postoperative total knee score (P = 0.18) or functional score (P = 0.23).
  
  
  CONCLUSIONS
  The meta-analysis showed that compared with conventional polyethylene, HXLPE did not improve the clinical and radiographic outcomes in mid-term follow-up after TKA. Additional high-quality multicenter prospective RCTs with good design, large study populations and long-term follow-up will be necessary to further clarify the effect of HXLPE in TKA.
authors.affiliation: Department of Orthopedics, The Third Affiliated Hospital of Wenzhou Medical College, Wenzhou, 325200, People's Republic of China.
authors.forename: Bin-feng
authors.initials: BF
authors.lastname: Yu
authors.affiliation: Department of Orthopedics, The Third Affiliated Hospital of Wenzhou Medical College, Wenzhou, 325200, People's Republic of China. yangguojing1965@126.com.
authors.forename: Guo-jing
authors.initials: GJ
authors.lastname: Yang
authors.affiliation: Department of Orthopedics, The Third Affiliated Hospital of Wenzhou Medical College, Wenzhou, 325200, People's Republic of China.
authors.forename: Wei-liang
authors.initials: WL
authors.lastname: Wang
authors.affiliation: Department of Orthopedics, The Third Affiliated Hospital of Wenzhou Medical College, Wenzhou, 325200, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, The Third Affiliated Hospital of Wenzhou Medical College, Wenzhou, 325200, People's Republic of China.
authors.forename: Xi-peng
authors.initials: XP
authors.lastname: Lin
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D003432:Cross-Linking Reagents; D006801:Humans; D007720:Knee Prosthesis; D010014:Osteolysis / Q000209:etiology; D020959:Polyethylene / Q000737:chemistry*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation / Q000706:statistics & numerical data
chemical_list: D003432:Cross-Linking Reagents; D020959:Polyethylene
keywords: Cross-linked; Knee arthroplasty; Meta-analysis; Polyethylene; Wear