title: A study of polyethylene and modularity issues in >1000 posterior cruciate-retaining knees at 5 to 11 years.
abstract: Polyethylene quality and production technique and monoblock versus modular design of tibial components affect the polyethylene wear of total knee arthroplasties (TKAs). We reviewed >1000 TKAs performed with the AGC prosthesis (Biomet, Warsaw, IN) using a uniform surgical technique with a 5- to 11-year follow-up. Of tibial components, 698 were of compression-molded monoblock design and 353 were of ram-extruded modular assembly design. The effect of the differences in tibial component design on the 5- to 11-year clinical and radiologic outcomes was studied. Higher rates of osteolysis, radiolucent lines, and revision were found with the ram-extruded modular design. This modular design is similar to most tibial component designs currently used in TKA, yet osteolysis in completely cemented components is described rarely. The TKAs done with a compression-molded monoblock design gave better clinical and radiologic results. The improved results may be due to polyethylene quality, assembly design, or a combination of these factors.
authors.affiliation: Advanced Orthopaedic Centers, Richmond, Virginia 23294, USA.
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Weber
authors.forename: Richard L
authors.initials: RL
authors.lastname: Worland
authors.forename: Jonathan
authors.initials: J
authors.lastname: Keenan
authors.forename: Jacob
authors.initials: J
authors.lastname: Van Bowen
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D020959:Polyethylene; D011474:Prosthesis Design; D012086:Reoperation
chemical_list: D020959:Polyethylene