Scientific Articles   |    
Comparison of Short and Long Arm Plaster Casts for Displaced Fractures in the Distal Third of the Forearm in Children
Gavin R. Webb, MD1; Robert D. Galpin, MD, FRCSC2; Douglas G. Armstrong, MD3
1 Seacoast Orthopedics and Sports Medicine, Marsh Brook Professional Center, 237 Route 108, Somersworth, NH 03878-1517. E-mail address: gavinwebb@md.aaos.org
2 Department of Orthopaedics, The Women's and Children's Hospital of Buffalo, 219 Bryant Street, Buffalo, NY 14222. E-mail address: rgalpin@acsu.buffalo.edu
3 Department of Orthopedics, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44120. E-mail address: douglas.armstrong@uhhs.com
View Disclosures and Other Information
A commentary is available with the electronic versions of this article, on our web site (www.jbjs.org) and on our quarterly CD-ROM (call our subscription department, at 781-449-9780, to order the CD-ROM).
The authors did not receive grants or outside funding in support of their research for or preparation of this manuscript. They did not receive 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.
Investigation performed at The Women's and Children's Hospital of Buffalo, Buffalo, New York

The Journal of Bone and Joint Surgery, Incorporated
J Bone Joint Surg Am, 2006 Jan 01;88(1):9-17. doi: 10.2106/JBJS.E.00131
5 Recommendations (Recommend) | 3 Comments | Saved by 3 Users Save Case


Background: Various methods of cast immobilization have been recommended for the treatment of distal forearm fractures in children. The purpose of this study was to determine if short arm casts are as effective as long arm casts in the treatment of displaced fractures of the distal third of the forearm in these patients.

Methods: In a prospective randomized trial, consecutive patients, four years of age or older, who presented to The Women's and Children's Hospital of Buffalo with a displaced fracture of the distal third of the forearm were randomized to treatment with a short or long arm plaster cast. Radiographs were analyzed for displacement, angulation, and deviation at the time of injury, after reduction, and at subsequent follow-up intervals. The cast index at the fracture level, used to assess the quality of the cast molding, was determined from the postreduction radiographs. Changes between postreduction and final values for displacement, angulation, and deviation; the ranges of motion of both wrists and elbows; the need for physical therapy; and responses to a questionnaire used to evaluate the effects of the cast on activities of daily living were compared between the groups.

Results: One hundred and thirteen of the 151 patients who were assessed for eligibility were analyzed. The follow-up rate was 92%, and the average duration of follow-up was eight months. Sixty long arm casts and fifty-three short arm casts were used. There were no significant differences between the two groups with regard to patient demographics, initial fracture characteristics, mechanism of injury, cast index, or the change in displacement, angulation, or deviation during treatment. The fractures that lost reduction in the cast had significantly higher cast indices, indicating poor cast-molding. A comparison of partially and completely displaced fractures revealed no difference between the groups with regard to the change between the postreduction and final amount of displacement. Patients treated with a short arm cast missed fewer school days and were less likely to require assistance with various activities of daily living.

Conclusions: A well-molded short arm cast can be used as effectively as a long arm cast to treat fractures of the distal third of the forearm in children four years of age and older, and they interfere less with daily activities.

Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

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

    Gavin R. Webb, M.D.
    Posted on March 12, 2006
    Dr. Webb responds to Dr. Kumar
    Seacoast Orthopedics and Sports Medicine, Somersworth, NH

    I would like to thank Dr. Kumar for his interest in our study and for raising several important questions. The first issue raised is the explanation for the higher failure rate in the long-arm cast group. As stated in the paper, this result was unexpected. Dr. Kumar suggests that this may be related to the fact that a larger number of the fractures treated in long-arm casts involved both the radius and ulna. As seen in figure 3, there was no significant difference in the distribution of fracture types when they were looked at individually. However, it does appear that when grouped by radius only vs. both bones, there is an uneven distribution (26 short arm and 38 long arm). When all fractures involving both bones are considered, these accounted for 26/53 (49.2%) of the short arm casts, and 38/60 (63.3%) of the long arm casts. Out of those 26 both bone fractures treated in short arm casts, only one failed (3.8%). Out of the 38 treated in long arm casts, there were 7 failures (18.4%). If the uneven distribution were the only explanation for the greater number of failures seen in the long-arm group, the total number of failures would be larger, but the rate of failure should be similar between the cast groups. Examining all of the failures, 8/11 (72.3%) involved fractures of both bones, whereas 6/11 (54.5%) were complete fractures. It does appear that instability may be more closely related to the involvement of both bones than to the amount of initial displacement.

    The study by Bohm, et al, (1) published in the same issue, found that fractures involving the radius and ulna had a higher risk of losing reduction. As far as lumping together ‘stable’ and ‘unstable’ fractures, the numbers available in each specific subgroup in our study, unfortunately, were not large enough to conduct a meaningful statistical analysis without grouping them together.

    The theoretical need to immobilize the elbow to prevent forearm rotation has certainly been a major historical argument for the need to use long-arm casts to treat these fractures. This notion along with a basic fracture principal that the joint proximal and distal to the fracture must be immobilized is a major reason this prospective randomized trial was undertaken. Both of these ideas are logical, but have not been supported by any clinical trials.

    The question of the source of error in determining cast index raises a valid point. The distance from the x-ray tube to the x-ray plate was not measured in the study. However, if there were a systematic bias, one would expect to see a statistical difference in the average cast index between the short and long-arm casts, which was not seen. The only significant difference in the cast indices was seen in the cases that lost reduction. There should not have been any reason that long-arm cases that lost reduction were positioned any differently than those than maintained it.

    In response to the final question raised, the results of our study suggest that it is as safe to treat a fracture of the distal third of the radius, ulna or both bones with a short-arm cast as it is with a long-arm cast. Fractures of the distal radial shaft were not specifically examined as a separate subgroup, but were included in both the long and short arm groups.

    Even with the weaknesses of our study, taken with the results of the similar prospective randomized controlled trial by Bohm, et al,(1) we believe there is now strong clinical evidence that fractures of the distal third of the forearm in children can be safely and effectively treated with well -molded short-arm plaster casts.


    1. Bohm ER, Bubbar V, Hing KY, Dzus A. Above and Below-the-Elbow Plaster Casts for Distal Forearm Fractures in Children. Journal of Bone and Joint Surgery. 2006;88:1-8.

    Gunasekaran Kumar
    Posted on February 26, 2006
    A Comparison of Short and Long Arm Plaster Casts
    Worthing and Southlands Hospitals NHS Trust, Worthing, U.K.

    To The Editor:

    I read with interest the paper, ‘Comparison of Short and Long Arm Plaster Casts for Displaced Fractures in the Distal Third of the Forearm in Children.’ by GR Webb, et al (1). I congratulate the authors on performing a prospective randomised trial, but I would ask them to respond to a number of remaining and important questions.

    One of the results of this paper is that long arm casts have a higher failure rate than short arm casts. A possible reason described by the authors is that they ‘are technically more difficult to apply, which results in poorer molding around the forearm’. However, the authors’ method of applying a long arm cast was to apply a moulded short arm cast first and then convert it into a long arm cast. An extension of a short arm cast to a long arm cast should not be technically more difficult than applying a short arm cast alone. A more likely explanation for the disproportionate failure of long arm casts could be that more long arm casts were used to treat the ‘unstable’ variety of distal radius shaft fractures. From Fig 3, when both the radius and the ulna were fractured (combining partially and completely displaced fractures as a group,) only 11 short arm casts were used compared to 20 long arm casts. Thus, the numbers were not evenly distributed between the two cast groups.

    Many would agree that managing a partially dorsally displaced Salter Harris type II distal radius fracture with closed reduction and a short arm cast is an appropriate procedure as it is a ‘stable’ fracture after reduction. However, a fracture of the distal diaphysis of the radius is not as stable as the physeal injury post reduction. Lumping together ‘stable’ and ‘unstable’ fractures does not allow us to judge whether short arm casts are appropriate for the ‘unstable’ variety of distal forearm fractures.

    Unstable distal shaft of radius fractures with volar angulation (which very often include a variety of distal ulna fractures) can be immobilised with the wrist held in pronation or supination or neutral rotation.(2) No matter which rotational position is chosen, a short arm cast cannot successfully prevent supination in a wrist that is held in pronation and vice versa. Hence, theoretically, there is a higher risk of loss of reduction in these distal radius shaft fractures.

    The authors, while discussing causes of error in the cast index, did not mention the distance from the X-ray tube to the X-ray plate which may not necessarily be the same when the antero posterior and lateral views are taken. This could bias against the long arm cast group as they are the ones that have more difficulty in changing position of the forearm for the two radiographs.

    A long arm cast does limit a patient’s daily activities and does prolong recuperation time but that alone should not decide how a distal shaft of radius fracture should be managed.

    The authors have not addressed the question that I would have liked them to answer: ‘Is it safer to manage a distal radius shaft (from metaphysis to distal third of the shaft) fracture in a short arm cast?’


    1. Webb GR, Galpin RD, Armstrong DG. Comparison of Short and Long Arm Plaster Casts for Displaced Fractures in the Distal Third of the Forearm in Children. Journal of Bone and Joint Surgery (American). 2006;88:9-17.

    2. O’Brien ET. Fractures of the hand and wrist region. In Rockwood Jr, CA, Wilkins KE, King RE, editors Fractures in children. Vol.3 Rockwood and Green, 3rd ed. Philadelphia: JB Lippincott; 1991. p384 -386.

    Related Content
    The Journal of Bone & Joint Surgery
    JBJS Case Connector
    Topic Collections
    Related Audio and Videos
    PubMed Articles
    ACR Appropriateness Criteria® acute hand and wrist trauma. -American College of Radiology | 7/17/2009
    Treatment of pediatric diaphyseal femur fractures. -American Academy of Orthopaedic Surgeons (AAOS) | 7/17/2009
    Results provided by:
    Clinical Trials
    Readers of This Also Read...
    JBJS Jobs
    W. Virginia - Charleston Area Medical Center
    District of Columbia (DC) - Children's National Medical Center
    New York - Icahn School of Medicine at Mount Sinai
    S. Carolina - Department of Orthopaedic Surgery Medical Univerity of South Carlonina