This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow CME: Take the exam for this article:
 CME 4: October, November, December 2003
Right arrow Letters to the Editor: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when Letters to the Editor are posted
Right arrow Alert me if a correction is posted
Services
Right arrow E-mail this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My File Cabinet
Right arrow Download to citation manager
Right arrowReprints and Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hermida, J. C.
Right arrow Articles by D'Lima, D. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hermida, J. C.
Right arrow Articles by D'Lima, D. D.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us   Add to Technorati  
What's this?
The Journal of Bone and Joint Surgery (American) 85:2325-2331 (2003)
© 2003 The Journal of Bone and Joint Surgery, Inc.

Comparison of the Wear Rates of Twenty-eight and Thirty-two-Millimeter Femoral Heads on Cross-Linked Polyethylene Acetabular Cups in a Wear Simulator

Juan C. Hermida, MD1, Arnie Bergula, BS1, Peter Chen, PhD1, Clifford W. Colwell, Jr., MD1 and Darryl D. D'Lima, MD1

1 Scripps Clinic, 11025 North Torrey Pines Road, Suite 140, La Jolla, CA 92037. E-mail address for C.W. Colwell Jr.: colwell{at}scripps.edu

Investigation performed at the Orthopaedic Research Laboratories, Scripps Clinic Center for Orthopaedic Research and Education, La Jolla, California

In support of their research or preparation of this manuscript, one or more of the authors received grants or outside funding from Howmedica Osteonics. None of the authors received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated.

Background: The use of larger femoral head sizes in total hip arthroplasty has been shown to reduce the rate of dislocation and to increase the range of motion; however, such components have been associated with unacceptably high polyethylene wear rates. Studies have shown dramatic differences in wear rates between nominally cross-linked polyethylene (i.e., polyethylene that is cross-linked during radiation sterilization) and elevated cross-linked polyethylene (i.e., polyethylene that is cross-linked to a higher degree than that obtained by radiation sterilization alone). The aim of this study was to test the effect of increased cross-linking and of increased head size on polyethylene wear rates.

Methods: Four groups of acetabular liners obtained from a single manufacturer, including 28-mm-diameter nominally cross-linked, 32-mm-diameter nominally cross-linked, 28-mm-diameter elevated cross-linked, and 32-mm-diameter elevated cross-linked polyethylene liners, were tested. Three implants from each group were tested in a twelve-station hip wear simulator with use of 90% bovine serum as a lubricant. The liners were articulated with the appropriately sized cobalt-chromium femoral head. Additional liners from each design were subjected only to the same load without motion to serve as load-soak controls to account for any weight gain due to fluid absorption. Gravimetric analysis was performed every 500,000 cycles for a total of five million cycles.

Results: Nominally cross-linked liners demonstrated mean wear rates of 14.97 and 16.92 mg per million cycles for the 28-mm and 32-mm head sizes, respectively. Both of the elevated cross-linked liners had significantly lower wear rates than the nominally cross-linked liners, with a mean of 1.51 and 2.57 mg per million cycles for the 28-mm and 32-mm head sizes, respectively (p < 0.001).

Conclusion and Clinical Relevance: The dramatic reduction in wear rates with polyethylene cross-linking, even with the larger head size, may increase the potential for use of 32-mm head components in total hip arthroplasty.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Technorati Technorati    What's this?


This article has been cited by other articles:


Home page
 JBJSHome page
C. A. Jacobs, C. P. Christensen, A. S. Greenwald, and H. McKellop
Clinical Performance of Highly Cross-Linked Polyethylenes in Total Hip Arthroplasty
J. Bone Joint Surg. Am., December 1, 2007; 89(12): 2779 - 2786.
[Abstract] [Full Text] [PDF]

Home page
 JBJSHome page
S. S. Tower, J. H. Currier, B. H. Currier, K. A. Lyford, D. W. Van Citters, and M. B. Mayor
Rim Cracking of the Cross-Linked Longevity Polyethylene Acetabular Liner After Total Hip Arthroplasty
J. Bone Joint Surg. Am., October 1, 2007; 89(10): 2212 - 2217.
[Abstract] [Full Text] [PDF]

Home page
 J Am Acad Orthop SurgHome page
A. C. Gordon, D. D. D'Lima, and C. W. Colwell Jr
Highly Cross-linked Polyethylene in Total Hip Arthroplasty.
J. Am. Acad. Ortho. Surg., September 1, 2006; 14(9): 511 - 523.
[Abstract] [Full Text] [PDF]