title: Long-term durability of alumina ceramic heads in THA.
abstract: BACKGROUND
  The optimal type of bearing for hip arthroplasty remains a matter of debate. Ceramic-on-polyethylene (CoP) bearings are frequently used in younger and more active patients to reduce wear and increase biocompatibility compared to Metal-on-Polyethylene (MoP) bearings. However, in comparison to metal heads, the fracture risk of ceramic heads is higher. In addition, ceramic head fractures pose a serious complication which often necessitates major revision surgery. To date, there are no long-term data (>20 years of follow-up) reporting fracture rates of the ceramic femoral heads in CoP bearings. The purpose of this research was to investigate long-term CoP fracture rate.
  
  
  METHODS
  We evaluated the clinical and radiographic results of 348 cementless THAs treated with 2nd generation Biolox Al₂O₃ Ceramic-on-Polyethylene (CoP) bearings consecutively implanted between January 1985 and December 1989. The mean age at implantation was 57 years. The patients were followed for a minimum of 20 years. At the final 111 had died, and 5 were lost to follow-up. The cumulative incidence of ceramic head fractures in the long-term was estimated using a competing risk analysis.
  
  
  RESULTS
  The cumulative incidence of ceramic head fracture after 22-years was estimated with a competing risk analysis at 0.29% after 22-years (SE = 2.09%; 95% - CI: 0.03-1.5%). The radiographic analysis revealed no impending failures at final follow-up.
  
  
  CONCLUSIONS
  The fracture rate of second-generation ceramic heads using a CoP articulation remains very low into the third decade after cementless THA.
authors.affiliation: Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Schlierbacher Landstrasse 200A, 69118, Heidelberg, Germany. nicholas.beckmann@med.uni-heidelberg.de.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Beckmann
authors.affiliation: Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Schlierbacher Landstrasse 200A, 69118, Heidelberg, Germany. tobias.gotterbarm@med.uni-heidelberg.de.
authors.forename: Tobias
authors.initials: T
authors.lastname: Gotterbarm
authors.affiliation: Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Schlierbacher Landstrasse 200A, 69118, Heidelberg, Germany. moritz.innmann@med.uni-heidelberg.de.
authors.forename: Moritz M
authors.initials: MM
authors.lastname: Innmann
authors.affiliation: Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Schlierbacher Landstrasse 200A, 69118, Heidelberg, Germany. christian.merle@med.uni-heidelberg.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Merle
authors.affiliation: Institute of Medical Biometry and Informatics, University of Heidelberg, Im Neuenheimer Feld 305, 69120, Heidelberg, Germany. bruckner@imbi.uni-heidelberg.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bruckner
authors.affiliation: Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Schlierbacher Landstrasse 200A, 69118, Heidelberg, Germany. philippe.kretzer@med.uni-heidelberg.de.
authors.forename: J Philippe
authors.initials: JP
authors.lastname: Kretzer
authors.affiliation: Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Schlierbacher Landstrasse 200A, 69118, Heidelberg, Germany. marcus.streit@med.uni-heidelberg.de.
authors.forename: Marcus R
authors.initials: MR
authors.lastname: Streit
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000537:Aluminum Oxide / Q000008:administration & dosage*; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation* / Q000639:trends*; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis / Q000592:standards / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design / Q000592:standards / Q000639:trends*; D011475:Prosthesis Failure / Q000639:trends*; D013997:Time Factors; D055815:Young Adult
chemical_list: D000537:Aluminum Oxide