Scientific Article   |    
Contribution of Monoblock and Bipolar Radial Head Prostheses to Valgus Stability of the Elbow
Stanislaw Pomianowski, MD, PhD; Bernard F. Morrey, MD; Patricia G. Neale, MS; Min J. Park, MD; Shawn W. O'Driscoll, MD, PhD; Kai Nan An, PhD
View Disclosures and Other Information
Investigation performed at the Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic and Mayo Foundation, Rochester, Minnesota

Stanislaw Pomianowski, MD, PhD
Bernard F. Morrey, MD
Patricia G. Neale, MS
Min J. Park, MD
Shawn W. O’Driscoll, MD, PhD
Kai Nan An, PhD
Department of Orthopedics, Mayo Clinic, 200 First Street S.W., ­Rochester, MN 55905

In support of their research or preparation of this manuscript, one or more of the authors received grants or outside funding from the Mayo Foundation and S. Pomianowski received a National Institutes of Health Grant from Fogarty International Center TW05377. None of the authors received payments or a commitment or agreement to provide such payments from a commercial entity. Radial head implants were supplied by Wright Medical Technology, Incorporated; Technika Medyczna Company; and Tornier SA Company. 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.

J Bone Joint Surg Am, 2001 Dec 01;83(12):1829-1834
5 Recommendations (Recommend) | 3 Comments | Saved by 3 Users Save Case


Background: The purpose of this study was to evaluate the stabilizing effect of radial head replacement in cadaver elbows with a deficient medial collateral ligament.

Methods: Passive elbow flexion with the forearm in neutral rotation and in 80° of pronation and supination was performed under valgus and varus loads (1) in intact elbows, (2) after a surgical approach (lateral epicondylar osteotomy of the distal part of the humerus), (3) after release of the anterior bundle of the medial collateral ligament, (4) after release of the anterior bundle of the medial collateral ligament and resection of the radial head, and (5) after subsequent replacement of the radial head with each of three different types of radial head prostheses (a Wright monoblock titanium implant, a KPS bipolar Vitallium [cobalt-chromium]-polyethylene implant, and a Judet bipolar Vitallium-polyethylene-Vitallium implant) in the same cadaver elbow. Total valgus elbow laxity was quantified with use of an electromagnetic tracking device.

Results: The mean valgus laxity changed significantly (p < 0.001) as a factor of constraint alteration. The greatest laxity was observed after release of the medial collateral ligament together with resection of the radial head (11.1° ± 5.6°). Less laxity was seen following release of the medial collateral ligament alone (6.8° ± 3.4°), and the least laxity was seen in the intact state (3.4° ± 1.6°). Forearm rotation had a significant effect (p = 0.003) on valgus laxity throughout the range of flexion. The laxity was always greater in pronation than it was in neutral rotation or in supination. The mean valgus laxity values for the elbows with a deficient medial collateral ligament and an implant were significantly greater than those for the medial collateral ligament-deficient elbows before radial head resection (p < 0.05). The implants all performed similarly except in neutral forearm rotation, in which the elbow laxity associated with the Judet implant was significantly greater than that associated with the other two implants.

Conclusions and Clinical Relevance: This study showed that a bipolar radial head prosthesis can be as effective as a solid monoblock prosthesis in restoring valgus stability in a medial collateral ligament-deficient elbow. However, none of the prostheses functioned as well as the native radial head, suggesting that open reduction and internal fixation to restore radial head anatomy is preferable to replacement when possible.

Figures in this Article
    Sign In to Your Personal ProfileSign In To Access Full Content
    Not a Subscriber?
    Get online access for 30 days for $35
    New to JBJS?
    Sign up for a full subscription to both the print and online editions
    Register for a FREE limited account to get full access to all CME activities, to comment on public articles, or to sign up for alerts.
    Register for a FREE limited account to get full access to all CME activities
    Have a subscription to the print edition?
    Current subscribers to The Journal of Bone & Joint Surgery in either the print or quarterly DVD formats receive free online access to JBJS.org.
    Forgot your password?
    Enter your username and email address. We'll send you a reminder to the email address on record.

    Forgot your username or need assistance? Please contact customer service at subs@jbjs.org. If your access is provided
    by your institution, please contact you librarian or administrator for username and password information. Institutional
    administrators, to reset your institution's master username or password, please contact subs@jbjs.org


    Accreditation Statement
    These activities have been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education (ACCME) through the joint sponsorship of the American Academy of Orthopaedic Surgeons and The Journal of Bone and Joint Surgery, Inc. The American Academy of Orthopaedic Surgeons is accredited by the ACCME to provide continuing medical education for physicians.
    CME Activities Associated with This Article
    Submit a Comment
    Please read the other comments before you post yours. Contributors must reveal any conflict of interest.
    Comments are moderated and will appear on the site at the discretion of JBJS editorial staff.

    * = Required Field
    (if multiple authors, separate names by comma)
    Example: John Doe

    Related Content
    The Journal of Bone & Joint Surgery
    JBJS Case Connector
    Topic Collections
    Related Audio and Videos
    Results provided by:
    Clinical Trials
    Readers of This Also Read...
    JBJS Jobs
    Massachusetts - Boston Medical Center and Boston University School of Medicine
    Virginia - OrthoVirginia
    OH - University Hospitals Case Medical Center
    CT - Yale University School of Medicine