Scientific Articles   |    
Contralateral Elbow Radiographs Can Reliably Diagnose Radial Head Implant Overlengthening
George S. Athwal, MD, FRCSC1; Dominique M. Rouleau, MD, MSc, FRCSC2; Joy C. MacDermid, BScPT, MSc, PhD1; Graham J.W. King, MD, MSc, FRCSC1
1 Hand and Upper Limb Centre, St. Josephs Health Care, University of Western Ontario, 268 Grosvenor Street, London, ON N6A 4L6, Canada. E-mail address for G.S. Athwal: gathwal@uwo.ca
2 University of Montreal, Hôpital Sacré-Coeur, 5400 boulevard Gouin Ouest, Montreal, QC H4J 1C5, Canada
View Disclosures and Other Information
Disclosure: One or more of the authors received payments or services, either directly or indirectly (i.e., via his or her institution), from a third party in support of an aspect of this work. One or more of the authors, or his or her institution, has had a financial relationship, in the thirty-six months prior to submission of this work, with an entity in the biomedical arena that could be perceived to influence or have the potential to influence what is written in this work. No author has had any other relationships, or has engaged in any other activities, that could be perceived to influence or have the potential to influence what is written in this work. The complete Disclosures of Potential Conflicts of Interest submitted by authors are always provided with the online version of the article.

  • Disclosure statement for author(s): PDF

Investigation performed at the University of Western Ontario, London, Ontario, Canada

Copyright © 2011 by The Journal of Bone and Joint Surgery, Inc.
J Bone Joint Surg Am, 2011 Jul 20;93(14):1339-1346. doi: 10.2106/JBJS.J.01244
5 Recommendations (Recommend) | 3 Comments | Saved by 3 Users Save Case



Excessive lengthening of the radius with use of a radial head implant, a common cause of capitellar wear and clinical failure, is difficult to identify on radiographs of the injured elbow. The purpose of this study was to determine if a novel measurement technique based on radiographs of the contralateral elbow could be used to accurately estimate the magnitude of overlengthening due to the radial head implant. In part I of this study, we examined the side-to-side consistency of radiographic landmarks used in the measurement technique. In part II, the technique was validated in a cadaveric model with simulated radial head implant overlengthening.


In part I of the study, a side-to-side comparison of elbow joint dimensions was performed with use of 100 radiographs from fifty patients. In part II, radial head prostheses of varying lengths (leading to 0, 2, 4, 6, and 8 mm of overlengthening) were implanted in four pairs of cadaveric specimens (eight elbows). Radiographic measurements were performed by two examiners blinded to the implant size to determine if radiographs of the contralateral elbow could be used to diagnose, and provide a valid estimate of the magnitude of, implant overlengthening. Intrarater and interrater reliability ratios, absolute measurement errors, and diagnostic accuracy were determined.


No significant side-to-side differences (p > 0.2) in radiographic measurements were identified between paired elbows. In the cadaveric model, the measurement technique involving use of radiographs of the contralateral elbow was successful in predicting the implant size (± 1 mm) in 104 (87%) of the 120 scenarios tested. The sensitivity of the technique—i.e., the ability of the test to correctly identify overlengthening (within ± 1 mm) when it was present—was 98%, with a positive likelihood ratio of 49 and a negative likelihood ratio of 0.02. The reliability of the radiographic measurements, based on repeated measurements performed by a single blinded orthopaedic surgeon on two separate occasions or based on separate measurements performed by two different orthopaedic surgeons, was excellent (intraclass correlation coefficient > 0.95).


A measurement technique based on radiographs of the contralateral elbow can be used to diagnose and calculate the magnitude of radial overlengthening due to the use of an incorrectly sized radial head implant.

Clinical Relevance: 

Implantation of a radial head prosthesis of incorrect size is not uncommon. The described technique can be used to diagnose and determine the magnitude of overlengthening of the radius.

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
    PubMed Articles
    Clinical Trials
    Readers of This Also Read...
    JBJS Jobs
    Virginia - OrthoVirginia
    Massachusetts - Boston Medical Center and Boston University School of Medicine
    DC - Children's National Medical Center
    LA - Ochsner Health System