0
Scientific Articles   |    
The Epidemiology of Neonatal Brachial Plexus Palsy in the United States
Susan L. Foad, MPH1; Charles T. Mehlman, DO, MPH1; Jun Ying, PhD2
1 Division of Pediatric Orthopaedic Surgery, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, MLC 2017, Cincinnati, OH 45229. E-mail address for S.L. Foad: Susan.foad@cchmc.org. E-mail address for C.T. Mehlman: Charles.mehlman@cchmc.org
2 Division of General Internal Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Institute for the Study of Health, P.O. Box 670840, Cincinnati, OH 45267-0840. E-mail address: yingj@ucmail.uc.edu
View Disclosures and Other Information
Disclosure: In support of their research for or preparation of this work, one or more of the authors received, in any one year, outside funding or grants of less than $10,000 from the University of Cincinnati Orthopaedic Research and Education Fund. Neither they nor a member of their immediate families 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, division, center, clinical practice, or other charitable or nonprofit organization with which the authors, or a member of their immediate families, are affiliated or associated.
Investigation performed at the Division of Pediatric Orthopaedic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, and the Division of General Internal Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Institute for the Study of Health, Cincinnati, Ohio

The Journal of Bone and Joint Surgery, Inc.
J Bone Joint Surg Am, 2008 Jun 01;90(6):1258-1264. doi: 10.2106/JBJS.G.00853
5 Recommendations (Recommend) | 3 Comments | Saved by 3 Users Save Case

Abstract

Background: The nationwide incidence of neonatal brachial plexus palsy in the United States is unknown. The purpose of this study was to determine the incidence of this condition in the United States and to identify potential risk factors for neonatal brachial plexus palsy.

Methods: Data from the 1997, 2000, and 2003 Kids' Inpatient Database data sets were utilized for this study. Patients were identified with use of the International Classification of Diseases, Ninth Revision (ICD-9), code 767.6 for neonatal brachial plexus palsy. Previously reported risk factors for this condition, including shoulder dystocia, instrumented delivery, breech delivery, an exceptionally large baby (>4.5 kg), heavy infant weight for gestational dates, multiple birth mates, and cesarean delivery, were also identified with use of ICD-9 codes. Multivariate logistic regression analysis was utilized to assess the association of neonatal brachial plexus palsy with its risk factors, after adjusting for sociodemographic characteristics, such as gender, race, and payer status; hospital-based characteristics, such as number of hospital beds, hospital location, region, type, and teaching status; and the effect of time.

Results: Over eleven million births were recorded in the database, and 17,334 had a documented brachial plexus injury in the total of three years, yielding a nationwide mean and standard error of incidence of neonatal brachial plexus palsy in the United States of at least 1.51 ± 0.02 cases per 1000 live births. The incidence of this condition has shown a significant decrease over the years (p < 0.01). In the multivariate analysis, shoulder dystocia had a 100 times greater risk, an exceptionally large baby (>4.5 kg) had a fourteen times greater risk, and forceps delivery had a nine times greater risk for injury. Having a twin or multiple birth mates and delivery by cesarean section had a protective effect against the occurrence of neonatal brachial plexus palsy. Forty-six percent of all children with neonatal brachial plexus palsy had one or more known risk factors, and fifty-four percent had no known risk factors.

Conclusions: This nationwide study of neonatal brachial plexus palsy in the United States demonstrates a decreasing incidence over time. Shoulder dystocia poses the greatest risk for brachial plexus injury, and having a twin or multiple birth mates and delivery by cesarean section are associated with a protective effect against injury. Most children with neonatal brachial plexus palsy did not have known risk factors.

Level of Evidence: Prognostic Level II. 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

    References

    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





    Susan L Foad, MPH
    Posted on September 23, 2008
    Dr. Foad and colleagues respond to Dr. Alfonso
    Cincinnati Children's Hospital Medical Center

    We thank Dr. Alfonso for his comments and we are pleased to respond. Following in the footsteps of our colleagues at The Texas Scottish Rite Hospital (1), we prefer to use the term "neonatal brachial plexus palsy" to describe such brachial plexus injuries in infants. The term “obstetrical brachial plexus palsy” is an out dated term that unfairly implies causation. Just as “Pediatrician hip dysplasia” is a term that would never be accepted to describe developmental dysplasia of the hip, we feel that we are at a point in time where we should no longer accept “obstetrical brachial plexus palsy.” We feel that our paper further supports this contention because the majority (54%) of infants with documented brachial plexus injuries had no identifiable risk factors

    Cases of neonatal brachial plexus palsy were identified using ICD-9 code(2), age of admission and type of admission from the Kids’ Inpatient Data Base (KIDS). The ICD-9 code 767.6 was defined as an injury to the brachial plexus, palsy or paralysis: brachial, Erb (Duchenne). Tumors, inflammation, or nondelivery–related trauma were not specified in the KIDS and hence could not be excluded in analyses. Nevertheless, we believe that they were rare cases and that their potential effects on our results would be trivial.

    Dr. Alfonso, has identified a limitation of utilizing a large national database. Data analysis is limited to variables that are collected in the database. Risk factors identified in our study from KIDS were limited only to variables contained in the infant discharge summary. Data regarding length of labor, space abnormalities, uterine malformation, etc would be reported in the mother’s discharge data and this data is not available from this database.

    1. Smith NC, Rowan P, Benson LJ, Ezaki M, Carter PR. Neonatal Brachial Plexus Palsy. Outcome Of Absent Biceps Function At Three Months Of Age. JBJS-A. 2004:86-A:2163-70.

    2. Hart AC, Hopkins CA ,eds. ICD-9-CM Expert for Physicians Volume 1 & 2. Ingenix; 2005.

    Israel Alfonso
    Posted on August 04, 2008
    Causes and Factors Involved In Neonatal Brachial Plexus Palsy
    Miami Children's Hospital and Florida International University

    To the Editor:

    We read with interest the article by Foad, et al(1). The authors appear to use the term neonatal brachial plexus palsy as a synonym for obstetrical brachial plexus palsy or brachial plexus birth injury. Were there any nonobstetrical causes of brachial plexus palsy, such as brachial plexus tumors, inflammation, or nondelivery-related trauma in their population?

    The article states that 54% of children with neonatal brachial plexus palsy had no known risk factors for this condition, yet the authors limited the studied variables to factors related to the magnitude of the stretching force acting upon the brachial plexus at the time of delivery: shoulder dystocia, instrumented delivery, breech delivery, cesarean delivery, an exceptionally large baby (an infant weighing >4.5 kg), heavy for dates (a fetus or infant larger for dates regardless of period of gestation) and twin or multiple birth-mate babies. This approach reduces the percentage of patients with known risk factors by ignoring conditions such as ultrashort second stage of labor, supracostoclavicular space abnormalities, conditions that limit arm motility during late gestation, maternal uterine malformations, and familial predisposition.(2-4). Can these risk factors be retrospectively analyzed in the study population?

    At our program we have taken a wider approach to the search for possible risk factors based on the following consideration and formula. The probability (p) of an obstetrical brachial plexus injury (obpi) is directly proportional to the magnitude of stretching force, which consists of the sum of the propulsive and traction forces exerted on the brachial plexus (pf + tf), the acceleration of the stretching force (a), and the parallelism (cos of ∠) between the vector of the stretching force and the axis of the most vulnerable brachial plexus segment (@ bp); and inversely proportional to the resistance (r) of the brachial plexus nerve bundles (n), shoulder girdle muscles (m) , joints (j) and bones (b).

    p of obpi = (pf + tf) a (cos of ∠) @ bp / r (n + m + j + b)

    This approach has led to the discovery of risk factors not related to the magnitude of the stretching force in some of our patients.

    The authors did not receive any outside funding or grants in support of their research for or preparation of this work. Neither they nor a member of their immediate families 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, division, center, clinical practice, or other charitable or nonprofit organization with which the authors, or a member of their immediate families, are affiliated or associated.

    REFERENCES

    1.Susan L. Foad, Charles T. Mehlman, and Jun Ying The Epidemiology of Neonatal Brachial Plexus Palsy in the United States J Bone Joint Surg Am 2008; 90: 1258-1264.

    2. Sandmire HF, DeMott RK. Erb’s palsy causation: A historical perspective. Birth. 2002;29 (1):52-54.

    3. Becker MH, Lassner F, Bahm J, Ingianni G, Pallua N. The cervical rib. A predisposing factor for obstetric brachial plexus lesions. J Bone Joint Surg Br. 2002;84(5):740-743.

    4. Alfonso I, Diaz-Arca G, Alfonso DT, Shuhaiber HH, Papazian O, Price AE, Grossman JA. Fetal deformations: A risk factor for obstetrical brachial plexus palsy? Pediatr Neurol. 2006;35(4):246-249.

    Related Content
    The Journal of Bone & Joint Surgery
    JBJS Case Connector
    Topic Collections
    Related Audio and Videos
    Clinical Trials
    Readers of This Also Read...
    JBJS Jobs
    12/04/2013
    New York - Icahn School of Medicine at Mount Sinai
    12/31/2013
    S. Carolina - Department of Orthopaedic Surgery Medical Univerity of South Carlonina
    02/28/2014
    District of Columbia (DC) - Children's National Medical Center
    04/02/2014
    W. Virginia - Charleston Area Medical Center