title: Younger age increases the risk of early prosthesis failure following primary total knee replacement for osteoarthritis. A follow-up study of 32,019 total knee replacements in the Finnish Arthroplasty Register.
abstract: OBJECTIVE
  Total knee replacements (TKRs) are being increasingly performed in patients aged < or = 65 years who often have high physical demands. We investigated the relation between age of the patient and prosthesis survival following primary TKR using nationwide data collected from the Finnish Arthroplasty Register.
  
  
  METHODS
  From Jan 1, 1997 through Dec 31, 2003, 32,019 TKRs for primary or secondary osteoarthritis were reported to the Finnish Arthroplasty Register. The TKRs were followed until the end of 2004. During the follow-up, 909 TKRs were revised, 205 (23%) due to infection and 704 for other reasons.
  
  
  RESULTS
  Crude overall implant survival improved with increasing age between the ages of 40 and 80. The 5-year survival rates were 92% and 95% in patients aged < or = 55 and 56-65 years, respectively, compared to 97% in patients who were > 65 years of age (p < 0.001). The difference was mainly attributable to reasons other than infections. Sex, diagnosis, type of TKR (condylar, constrained, or hinge), use of patellar component, and fixation method were also associated with higher revision rates. However, the differences in prosthesis survival between the age groups < or = 55, 56-65, and > 65 years remained after adjustment for these factors (p < 0.001).
  
  
  CONCLUSIONS
  Young age impairs the prognosis of TKR and is associated with increased revision rates for non-infectious reasons. Diagnosis, sex, type of TKR, use of patellar component, and fixation method partly explain the differences, but the effects of physical activity, patient demands, and obesity on implant survival in younger patients warrant further research.
authors.affiliation: Medical School, University of Tampere, Finland.
authors.forename: Jaakko
authors.initials: J
authors.lastname: Julin
authors.forename: Esa
authors.initials: E
authors.lastname: Jämsen
authors.forename: Timo
authors.initials: T
authors.lastname: Puolakka
authors.forename: Yrjö T
authors.initials: YT
authors.lastname: Konttinen
authors.forename: Teemu
authors.initials: T
authors.lastname: Moilanen
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D007720:Knee Prosthesis / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D011379:Prognosis; D011475:Prosthesis Failure; D012042:Registries; D012086:Reoperation; D012307:Risk Factors; D016896:Treatment Outcome
references.citation: Clin Orthop Relat Res. 2001 Nov;(392):315-8
references.pmid: 11716402
references.citation: J Arthroplasty. 2006 Sep;21(6):803-8
references.pmid: 16950030
references.citation: Clin Orthop Relat Res. 2006 Nov;452:44-8
references.pmid: 16906110
references.citation: Acta Orthop Scand. 2001 Oct;72(5):433-41
references.pmid: 11728068
references.citation: Acta Orthop. 2009 Apr;80(2):205-12
references.pmid: 19404805
references.citation: Acta Orthop. 2005 Feb;76(1):28-41
references.pmid: 15788305
references.citation: J Bone Joint Surg Br. 2008 Mar;90(3):360-3
references.pmid: 18310761
references.citation: J Arthroplasty. 1999 Dec;14(8):969-75
references.pmid: 10614889
references.citation: Acta Orthop Scand. 2001 Oct;72(5):503-13
references.pmid: 11728079
references.citation: Acta Orthop Scand Suppl. 1991;241:27-30
references.pmid: 2014738
references.citation: J Bone Joint Surg Br. 2006 Sep;88(9):1158-63
references.pmid: 16943464
references.citation: Clin Orthop Relat Res. 1998 Nov;(356):22-7
references.pmid: 9917663
references.citation: Clin Orthop Relat Res. 2006 May;446:45-50
references.pmid: 16672871
references.citation: J Bone Joint Surg Am. 2002 Feb;84(2):171-7
references.pmid: 11861721
references.citation: J Bone Joint Surg Am. 1997 Apr;79(4):575-82
references.pmid: 9111404
references.citation: J Arthroplasty. 2000 Feb;15(2):166-70
references.pmid: 10708080
references.citation: Clin Orthop Relat Res. 2000 Nov;(380):85-90
references.pmid: 11064977
references.citation: J Bone Joint Surg Br. 2007 Jul;89(7):893-900
references.pmid: 17673581
references.citation: Acta Orthop. 2005 Feb;76(1):85-8
references.pmid: 15788313
references.citation: J Bone Joint Surg Br. 2007 Dec;89(12):1608-14
references.pmid: 18057361
references.citation: J Bone Joint Surg Br. 2006 Oct;88(10):1321-6
references.pmid: 17012421
references.citation: Clin Orthop Relat Res. 2007 Nov;464:83-7
references.pmid: 17589362
references.citation: Knee. 2007 Jan;14(1):9-11
references.pmid: 17169563
references.citation: Clin Orthop Relat Res. 2004 Apr;(421):162-8
references.pmid: 15123942
references.citation: J Arthroplasty. 2005 Oct;20(7 Suppl 3):12-6
references.pmid: 16213997
references.citation: J Bone Joint Surg Am. 2008 Oct;90(10):2160-70
references.pmid: 18829914
references.citation: J Bone Joint Surg Am. 2003 Feb;85(2):259-65
references.pmid: 12571303
references.citation: Acta Orthop. 2008 Apr;79(2):230-4
references.pmid: 18484249
references.citation: N Engl J Med. 2002 Jul 11;347(2):81-8
references.pmid: 12110735
references.citation: J Bone Joint Surg Am. 2002 May;84(5):770-4
references.pmid: 12004019