This Article Full Text Full Text (PDF) CME: Take the exams for this article: Adult Hip Reconstruction Test 9: Topics of Interest in Hip Arthroplasty CME 3: July, August, September 2004 Letters to the Editor: Submit a response Letters to the Editor: View responses Alert me when this article is cited Alert me when Letters to the Editor are posted Alert me if a correction is posted Services E-mail this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to My File Cabinet Download to citation manager Reprints and Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Beaulé, P. E. Articles by Ebramzadeh, E. Search for Related Content PubMed PubMed Citation Articles by Beaulé, P. E. Articles by Ebramzadeh, E. Related Collections Adult Hip Social Bookmarking             What's this?

Orientation of the Femoral Component in Surface Arthroplasty of the Hip

A Biomechanical and Clinical Analysis

¹ Joint Replacement Institute at Orthopaedic Hospital, 2400 South Flower Street, Los Angeles, CA 90007. E-mail address for P.E. Beaulé: pbeaule{at}laoh.ucla.edu
² Department of Biomedical Engineering, University of Southern California, OHE 500, MC1451, University Park, Los Angeles, CA 90007. E-mail address: jessicll{at}usc.edu
³ Biomechanics Laboratory, Orthopaedic Hospital, 2400 South Flower Street, Los Angeles, CA 90007-2697

Investigation performed at the Joint Replacement Institute and the J. Vernon Luck Sr., MD, Orthopaedic Research Center, Orthopaedic Hospital/UCLA, Los Angeles, California

In support of their research or preparation of this manuscript, one or more of the authors received grants or outside funding from Los Angeles Orthopaedic Hospital Foundation and William G. McGowan Charitable Fund. In addition, one or more of the authors received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity (Wright Medical Technology). Also, a commercial entity (Wright Medical Technology) paid or directed, or agreed to pay or direct, benefits to a research fund, foundation, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated.

Methods: We reviewed the results of ninety-four hybrid metal-on-metal surface arthroplasties in patients who were forty years old or younger at the time of the operation and were followed for a minimum of two years or until the prosthesis failed. Measurements of the hip reconstruction were made on the anteroposterior pelvic radiograph. The correlation between the orientation of the femoral component and the outcome of the arthroplasty was evaluated, as were stresses within the resurfaced femoral head as a function of the orientation of the femoral component.

Results: The mean duration of follow-up was 4.2 years. Thirteen hips had an adverse outcome, defined as conversion to a total hip replacement, radiolucency of >1 mm in thickness adjacent to the femoral stem, or narrowing of the femoral neck of >10%. The mean femoral stem-shaft angle in the coronal plane was 138°, with the hips that had an adverse outcome having a significantly lower mean angle than the rest of the cohort (133° compared with 139°, p = 0.03). Hips with an angle of 130° had an increase in the relative risk of an adverse outcome by a factor of 6.1 (p < 0.004). In the entire cohort, stresses in the superior aspect of the resurfaced femoral head were substantially lower during slow walking than they were during fast walking (7.1 N/mm² compared with 14.2 N/mm²).

Conclusions: Optimizing the femoral stem-shaft angle toward a valgus orientation during the preparation of the femoral head is important when a hip is being reconstructed with a surface arthroplasty because the resurfaced hip transmits the load through a narrow critical zone in the femoral head-neck region and the valgus angulation may reduce these stresses.

Level of Evidence: Therapeutic study, Level III-2 (retrospective cohort study). See Instructions to Authors for a complete description of levels of evidence.

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

This article has been cited by other articles:

				J. C. Clohisy, P. E. Beaule, A. O'Malley, M. R. Safran, and P. Schoenecker AOA Symposium. Hip Disease in the Young Adult: Current Concepts of Etiology and Surgical Treatment J. Bone Joint Surg. Am., October 1, 2008; 90(10): 2267 - 2281. [Full Text] [PDF]

				T. P. Vail, R. R. Glisson, D. E. Dominguez, K. Kitaoka, and D. Ottaviano Position of Hip Resurfacing Component Affects Strain and Resistance to Fracture in the Femoral Neck J. Bone Joint Surg. Am., September 1, 2008; 90(9): 1951 - 1960. [Abstract] [Full Text] [PDF]

				J. P. Cobb, V. Kannan, W. Dandachli, F. Iranpour, K. U. Brust, and A. J. Hart Learning How to Resurface Cam-Type Femoral Heads with Acceptable Accuracy and Precision: The Role of Computed Tomography-Based Navigation J. Bone Joint Surg. Am., August 1, 2008; 90(Supplement_3): 57 - 64. [Abstract] [Full Text] [PDF]

				J. R. Romanowski and M. L. Swank Imageless Navigation in Hip Resurfacing: Avoiding Component Malposition During the Surgeon Learning Curve J. Bone Joint Surg. Am., August 1, 2008; 90(Supplement_3): 65 - 70. [Abstract] [Full Text] [PDF]

				T. M. Seyler, L. P. Lai, D. I. Sprinkle, W. G. Ward, and R. H. Jinnah Does Computer-Assisted Surgery Improve Accuracy and Decrease the Learning Curve in Hip Resurfacing? A Radiographic Analysis J. Bone Joint Surg. Am., August 1, 2008; 90(Supplement_3): 71 - 80. [Abstract] [Full Text] [PDF]

				K. L. Ong, M. T. Manley, and S. M. Kurtz Have Contemporary Hip Resurfacing Designs Reached Maturity? A Review J. Bone Joint Surg. Am., August 1, 2008; 90(Supplement_3): 81 - 88. [Abstract] [Full Text] [PDF]

				C. J. Richards, D. Giannitsios, O. L. Huk, D. J. Zukor, T. Steffen, and J. Antoniou Risk of Periprosthetic Femoral Neck Fracture After Hip Resurfacing Arthroplasty: Valgus Compared with Anatomic Alignment. A Biomechanical and Clinical Analysis J. Bone Joint Surg. Am., August 1, 2008; 90(Supplement_3): 96 - 101. [Abstract] [Full Text] [PDF]

				S. Williams, I. Leslie, G. Isaac, Z. Jin, E. Ingham, and J. Fisher Tribology and Wear of Metal-on-Metal Hip Prostheses: Influence of Cup Angle and Head Position J. Bone Joint Surg. Am., August 1, 2008; 90(Supplement_3): 111 - 117. [Abstract] [Full Text] [PDF]

				A. Shimmin, P. E. Beaule, and P. Campbell Metal-on-Metal Hip Resurfacing Arthroplasty J. Bone Joint Surg. Am., March 1, 2008; 90(3): 637 - 654. [Abstract] [Full Text] [PDF]

				H. C. Amstutz, J. T. Antoniades, and M. J. Le Duff Results of Metal-on-Metal Hybrid Hip Resurfacing for Crowe Type-I and II Developmental Dysplasia J. Bone Joint Surg. Am., February 1, 2007; 89(2): 339 - 346. [Abstract] [Full Text] [PDF]

				P. E. Beaule, P. Campbell, Z. Lu, K. Leunig-Ganz, M. Beck, M. Leunig, and R. Ganz Vascularity of the Arthritic Femoral Head and Hip Resurfacing J. Bone Joint Surg. Am., December 1, 2006; 88(suppl_4): 85 - 96. [Full Text] [PDF]

				M. H. Huo and N. F. Gilbert What's New in Hip Arthroplasty J. Bone Joint Surg. Am., September 1, 2005; 87(9): 2133 - 2146. [Full Text] [PDF]

				M. K. Sayana, R. A. Brand, J. D. Heckman, and J. Scott The Least Publishable Unit * R.A. Brand, J.D. Heckman, and J. Scott reply: J. Bone Joint Surg. Am., March 1, 2005; 87(3): 679 - 680. [Full Text]

Letters to the Editor:

Stanford University Libraries' HighWire Press (TM) assists in the publication of JBJS Online.
Copyright © 2004 by The Journal of Bone and Joint Surgery, Inc. Online ISSN: 1535-1386.
The Journal of Bone and Joint Surgery®, JBJS®, JB&JS®, and eJBJS® are registered in the U.S. Patent and Trademark Office.