title: Osteolysis in well-functioning fixed- and mobile-bearing TKAs in younger patients.
abstract: BACKGROUND
  Periprosthetic osteolysis is an increasingly prevalent complication of TKA. To reduce the polyethylene wear and periprosthetic osteolysis, particularly in young patients, the design of the contemporary fixed-bearing TKAs has been modified and mobile-bearing TKAs have been introduced.
  
  
  OBJECTIVE
  We asked whether the prevalence of osteolysis would be less in well-functioning mobile-bearing TKAs than in well-functioning contemporary fixed-bearing TKAs in young patients.
  
  
  METHODS
  We compared 488 patients (894 knees) who received fixed-bearing knee prostheses with 445 patients (816 knees) who received mobile-bearing knee prostheses. There were 187 men and 301 women (mean age, 58.6 years; range, 33-65 years) in the fixed-bearing group and 167 men and 278 women (mean age, 55.7 years; range, 33-65 years) in the mobile-bearing group. The mean followup was 12.6 years (range, 10-17 years) in the fixed-bearing group and 12.9 years (range, 10-17 years) in the mobile-bearing group.
  
  
  RESULTS
  The incidence of osteolysis was 1.6% (14 of 894 knees) in the fixed-bearing group and 2.2% (18 of 816 knees) in the mobile-bearing group at the final review. The mean postoperative Knee Society knee and function scores were 92.9 points and 83.5 points, respectively, in the fixed-bearing group and 90.7 points and 83.8 points, respectively, in the mobile-bearing group. The revision rates were 3.7% (33 of 894 knees) in the fixed-bearing group and 2.7% (22 of 816 knees) in the mobile-bearing group.
  
  
  CONCLUSIONS
  We found the incidence of osteolysis, rate of revision, and implant survivorship were similar between fixed-bearing and mobile-bearing TKAs in younger patients.
authors.affiliation: The Joint Replacement Center of Korea, Ewha Womans University School of Medicine, 911-1, MokDong, YangChun-Gu, Seoul, 158-710, Korea. younghookim@ewha.ac.kr
authors.forename: Young-Hoo
authors.initials: YH
authors.lastname: Kim
authors.forename: Yoowang
authors.initials: Y
authors.lastname: Choi
authors.forename: Jun-Shik
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000295:instrumentation; D005260:Female; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D015995:Prevalence; D011474:Prosthesis Design; D011475:Prosthesis Failure; D020127:Recovery of Function; D056910:Republic of Korea; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome