title: Cemented Müller straight stem total hip replacement: 18 year survival, clinical and radiological outcomes.
abstract: OBJECTIVE
  To present the 18 year survival and the clinical and radiological outcomes of the Müller straight stem, cemented, total hip arthroplasty (THA).
  
  
  METHODS
  Between 1989 and 2007, 176 primary total hip arthroplasties in 164 consecutive patients were performed in our institution by the senior author. All patients received a Müller cemented straight stem and a cemented polyethylene liner. The mean age of the patients was 62 years (45-78). The diagnosis was primary osteoarthritis in 151 hips, dysplasia of the hip in 12 and subcapital fracture of the femur in 13. Following discharge, serial follow-up consisted of clinical evaluation based on the Harris Hip Score and radiological assessment. The survival of the prosthesis using revision for any reason as an end-point was calculated by Kaplan-Meier analysis.
  
  
  RESULTS
  Twenty-four (15%) patients died during the follow-up study, 6 (4%) patients were lost, while the remaining 134 patients (141 hips) were followed-up for a mean of 10 years (3-18 years). HSS score at the latest follow-up revealed that 84 hips (59.5%) had excellent results, 30 (22.2%) good, 11 (7.8%) fair and 9 (6.3%) poor. There were 3 acetabular revisions due to aseptic loosening. Six (4.2%) stems were diagnosed as having radiographic definitive loosening; however, only 1 was revised. 30% of the surviving stems showed no radiological changes of radiolucency, while 70% showed some changes. Survival of the prosthesis for any reason was 96% at 10 years and 81% at 18 years.
  
  
  CONCLUSIONS
  The 18 year survival of the Müller straight stem, cemented THA is comparable to those of other successful cemented systems.
authors.affiliation: Vasileios S Nikolaou, Stergios Lallos, Ioannis Lazarettos, Ioannis Sourlas, Nicolas Efstathopoulos, 2 Orthopaedic Department, Athens University, 15124 Athens, Greece.
authors.forename: Vasileios S
authors.initials: VS
authors.lastname: Nikolaou
authors.forename: Demetrios
authors.initials: D
authors.lastname: Korres
authors.forename: Stergios
authors.initials: S
authors.lastname: Lallos
authors.forename: Andreas
authors.initials: A
authors.lastname: Mavrogenis
authors.forename: Ioannis
authors.initials: I
authors.lastname: Lazarettos
authors.forename: Ioannis
authors.initials: I
authors.lastname: Sourlas
authors.forename: Nicolas
authors.initials: N
authors.lastname: Efstathopoulos
keywords: Cemented; Muller; Replacement; Straight stem; Survivorship; Total hip