title: Cementing acetabular liners into secure cementless shells for polyethylene wear provides durable mid-term fixation.
abstract: BACKGROUND
  In a previous experiment studying cementation of liners into cementless acetabular shells, placing grooves in the liner in a spider-web configuration created the greatest construct strength. Scoring shells without screw holes or other texturing helped prevent failure at the shell-cement interface. However, it was unclear whether these practices caused durable constructs in patients.
  
  
  OBJECTIVE
  We therefore determined (1) rerevision rates; (2) functional scores (Harris hip scores, WOMAC, and SF-36); (3) acetabular loosening rates; and (4) acetabular osteolysis rates in patients in whom we cemented nonconstrained liners into well-fixed and well-positioned acetabular shells.
  
  
  METHODS
  We prospectively followed 30 patients with 31 total hip arthroplasties in which a worn acetabular liner was revised by cementing a new liner into the existing shell that was stable and well positioned. Acetabular liners were prepared as determined by our previous study. Twenty-seven of the 30 patients (28 hips) were evaluated clinically. We recorded revisions and determined radiographic loosening and osteolysis. The minimum clinical followup was 2 years (mean, 5.3 years; range, 2-10 years). Twenty-six hips (87%) had minimum 2-year radiographic followup with an average length of 4.8 years.
  
  
  RESULTS
  No hip required rerevision during the followup interval. Two hips (6%) dislocated once, both treated nonoperatively. Harris hip scores, WOMAC, and SF-36 scores increased over preoperatively at last followup. All acetabular shells and liners were radiographically stable without evidence of loosening or progressive acetabular osteolysis.
  
  
  CONCLUSIONS
  Cementation of a liner into a well-fixed cementless shell after scoring in a spider-web configuration provided secure fixation with no failures of the construct at average 5.3 years followup.
  
  
  METHODS
  Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: University of Iowa, 200 Hawkins Drive, 01029 JPP, UIHC, Iowa City, IA 52242, USA. john-callaghan@uiowa.edu
authors.forename: John J
authors.initials: JJ
authors.lastname: Callaghan
authors.forename: David W
authors.initials: DW
authors.lastname: Hennessy
authors.forename: Steve S
authors.initials: SS
authors.lastname: Liu
authors.forename: Kirsten E
authors.initials: KE
authors.lastname: Goetz
authors.forename: Anneliese D
authors.initials: AD
authors.lastname: Heiner
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001672:Biocompatible Materials; D001843:Bone Cements; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000517:prevention & control; D020959:Polyethylene; D011475:Prosthesis Failure; D012086:Reoperation
chemical_list: D001672:Biocompatible Materials; D001843:Bone Cements; D020959:Polyethylene