title: Backside wear is low in retrieved modern, modular, and nonmodular acetabular liners.
abstract: Modern modular components with maximized conformity between liner and shell, improved locking mechanisms, and smooth inner surfaces should have less backside wear than first-generation modular designs. Also, nonmodular components should show no backside wear in vivo. We compared the backside wear of retrieved liners from nonmodular and modular components from first-generation and second-generation designs. We matched for time in situ, patient age and weight for nine retrieved Harris-Galante Type 1 liners, nine Harris-Galante Type 2 liners, nine Trilogy liners, and nine Implex nonmodular liners. The backside of the liners was divided in quadrants, examined under a x10 binocular loupe, and rated by a score of 0 (absence of wear) to 3 (severe backside wear) for a total ranging from 0 to 12. The average total backside wear score was 8.4 for the Harris-Galante Type 1 liner, 7.3 for the Harris-Galante Type 2 liner, 3.7 for the Trilogy liner, and 2.3 for the Implex liner. We observed a significant reduction in the backside wear of modern modular and nonmodular acetabular components (Trilogy(R) and Implex) when compared with first-generation modular designs (Harris-Galante Types 1 and 2). Nonmodular acetabular cups had a low backside wear in vivo.
  
  
  METHODS
  Therapeutic study, Level III (retrospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Hospital for Special Surgery, New York, NY 10021, USA. gonzaleza@hss.edu
authors.forename: Alejandro González
authors.initials: AG
authors.lastname: Della Valle
authors.forename: Adam
authors.initials: A
authors.lastname: Rana
authors.forename: Bridgette
authors.initials: B
authors.lastname: Furman
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Sculco
authors.forename: Eduardo A
authors.initials: EA
authors.lastname: Salvati
mesh_terms: D000077:Acetabulum; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011475:Prosthesis Failure