title: The Rotaglide mobile-bearing total knee arthroplasty: no difference between cemented and hybrid implantation.
abstract: OBJECTIVE
  The optimal fixation of the Rotaglide total knee arthroplasty's (TKA) components is controversial. It is hypothesized that the hybrid fixation (cementless femoral component) in a mobile-bearing TKA system might cause increased rate of loosening--especially in the femoral part--and finally failure of the arthroplasty. Consequently, the aim of this study was to compare the survival and revision rates and also the clinical and radiological outcomes of the cemented and hybrid fixation of the Rotaglide TKA.
  
  
  METHODS
  One hundred patients, who underwent TKA with the Rotaglide prosthesis, were randomly placed in two groups. In the first group, the prosthesis was cemented, and in the second group, the hybrid technique was used. Revision and mortality rates were compared after 8-12 years of follow-up. Knee and Osteoarthritis Outcome Score (KOOS) questionnaire and the Knee Society Roentgenographic Evaluation and Scoring System were used to demonstrate clinical and radiographic differences.
  
  
  RESULTS
  There were no statistically significant differences in revision (n.s.) or mortality (n.s.) rates between the two treatment arms. The clinical outcome at the time of last follow-up (mean 9.5 years, SD ± 1.4) ranged from very good to excellent (77.8 ± 17.5 for the cemented group and 77.2 ± 20.4 for the hybrid group). No statistically significant differences in all KOOS subscales. Radiographs showed no significant difference in prosthesis alignment and no evidence of loosening between groups.
  
  
  CONCLUSIONS
  The hypothesis that the hybrid fixation in a mobile-bearing TKA system might cause increased rate of loosening and finally failure of the arthroplasty was not confirmed. The fixation technique (cemented or hybrid) had no influence on the prosthesis's survivorship, and also on mortality rates, clinical and radiographic outcomes in a mean follow-up time of 9.5 ± 1.4 years. The Rotaglide TKA is a safe and reliable prosthesis regardless the fixation technique.
authors.affiliation: 2nd Orthopaedic Department of "Papageorgiou", General Hospital, 56403, Periferiaki Odos, Thessaloníki, Greece, iosfyl@med.auth.gr.
authors.forename: Michael
authors.initials: M
authors.lastname: Iosifidis
authors.forename: Efthymios
authors.initials: E
authors.lastname: Iliopoulos
authors.forename: Dimos
authors.initials: D
authors.lastname: Neofytou
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Sakorafas
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Andreou
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Alvanos
authors.forename: Anastasios
authors.initials: A
authors.lastname: Kyriakidis
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D002484:Cementation; D005260:Female; D005269:Femur / Q000601:surgery; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D011446:Prospective Studies; D011474:Prosthesis Design; D016896:Treatment Outcome