The Journal of Bone and Joint Surgery (American). 2009;91:1578-1586.
doi:10.2106/JBJS.H.00282
© 2009 The Journal of Bone and Joint Surgery, Inc.
Fixation of a Trabecular Metal Knee Arthroplasty ComponentA Prospective Randomized Study
M.J. Dunbar, MD, FRCSC, PhD1,
D.A.J. Wilson, MASc, BEng1,
A.W. Hennigar, BSc1,
J.D. Amirault, MD, FRCSC1,
M. Gross, MBBS, FRCSC(LOND)1 and
G.P. Reardon, MD, FRCSC1
1 QEII Health Sciences Centre, 1796 Summer Street, Room 4822, Halifax, NS B3H 3A7, Canada. E-mail address for D.A.J. Wilson: wilsondaj{at}gmail.com
Investigation performed at the QEII Health Sciences Centre, Halifax, Nova Scotia, Canada
Disclosure: In support of their research for or preparation of this work, one or more of the authors received, in any one year, outside funding or grants in excess of $10,000 from Zimmer and the Canadian Institute of Health Research. In addition, one or more of the authors or a member of his or her immediate family received, in any one year, payments or other benefits in excess of $10,000 or a commitment or agreement to provide such benefits from commercial entities (Wright Medical Technology and Stryker).
A video supplement to this article will be available from the Video Journal of Orthopaedics. A video clip will be available at the JBJS web site, www.jbjs.org. The Video Journal of Orthopaedics can be contacted at (805) 962-3410, web site: www.vjortho.com.
A commentary is available with the electronic versions of this article, on our web site (www.jbjs.org) and on our quarterly CD-ROM/DVD (call our subscription department, at 781-449-9780, to order the CD-ROM or DVD).
Background: Uncemented tibial components of total knee replacements have lower survival rates than cemented components. Radiostereometric analysis is a highly accurate, effective tool for investigating new implant designs. The purpose of this study was to compare an uncemented Trabecular Metal tibial component with a conventional cemented stemmed tibial component of the same design.
Methods: Seventy subjects undergoing total knee replacement were randomized to receive either the Trabecular Metal or the cemented tibial component. Radiostereometric analysis of micromotion of the tibial components was performed postoperatively at six, twelve, and twenty-four months, and the maximum total point motion of the implant and three-dimensional translations and rotations were recorded.
Results: Follow-up was complete for twenty-eight subjects in the Trabecular Metal group and twenty-one subjects in the cemented group. A subset of the Trabecular Metal components migrated extensively in the postoperative period, but all stabilized by one year and the proportion considered to be at risk for early aseptic loosening was 0.0 (95% confidence interval, 0.0 to 0.12) in the group as a whole. Four cemented components were considered to be at risk for early aseptic loosening (proportion at risk, 0.19; 95% confidence interval, 0.08 to 0.4).
Conclusions: This study suggests that the Trabecular Metal component may be an effective alternative to the standard cemented tibial component.
Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

CiteULike Connotea Del.icio.us Facebook Technorati Twitter What's this?
|