0
Scientific Articles   |    
Anatomic Factors Related to the Cause of Tennis Elbow
Robert E. Bunata, MD1; David S. Brown, MD2; Roderick Capelo, MD2
1 4054 Hildring Drive West, Fort Worth, TX 76109. E-mail address: rbunata@hsc.unt.edu
2 2020 West Highway 114, Suite 110, Grapevine, TX 76051
View Disclosures and Other Information
Disclosure: 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.
Investigation performed at the University of North Texas Health Science Center—John Peter Smith Affiliated Orthopedic Residency Program, Fort Worth, Texas

The Journal of Bone and Joint Surgery, Incorporated
J Bone Joint Surg Am, 2007 Sep 01;89(9):1955-1963. doi: 10.2106/JBJS.F.00727
5 Recommendations (Recommend) | 3 Comments | Saved by 3 Users Save Case

Abstract

Background: The pathogenesis of lateral epicondylitis remains unclear. Our purpose was to study the anatomy of the lateral aspect of the elbow under static and dynamic conditions in order to identify bone-to-tendon and tendon-to-tendon contact or rubbing that might cause abrasion of the tissues.

Methods: Eighty-five cadaveric elbows were examined to determine details related to the bone structure and musculotendinous origins. We identified the relative positions of the musculotendinous units and the underlying bone when the elbow was in different degrees of flexion. We also recorded the contact between the extensor carpi radialis brevis and the lateral edge of the capitellum as elbow motion occurred, and we sought to identify the areas of the capitellum and extensor carpi radialis brevis where contact occurs.

Results: The average site of origin of the extensor carpi radialis brevis on the humerus lay slightly medial and superior to the outer edge of the capitellum. As the elbow was extended, the undersurface of the extensor carpi radialis brevis rubbed against the lateral edge of the capitellum while the extensor carpi radialis longus compressed the brevis against the underlying bone.

Conclusions: The extensor carpi radialis brevis tendon has a unique anatomic location that makes its undersurface vulnerable to contact and abrasion against the lateral edge of the capitellum during elbow motion.

Clinical Relevance: This information may help us to understand the pathomechanics of lateral epicondylitis and provide a better rationale for operative and nonoperative treatment.

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





    Robert E. Bunata, M.D.
    Posted on October 30, 2007
    Dr. Bunata et al. respond to Dr. LaBan
    University of North Texas Health Science Center, Fort Worth, TX

    We thank Dr. LaBan for his interest in our article. He raises two questions requiring a response and one minor modification.

    First, he asks “why are some more vulnerable to this injury than others?” We contend that some people have tendon and bone anatomy that results in the two structures rubbing against each other in such a way as to cause injury. Factors that come into play are the size and shape of the epicondyle and the capitellum, and the site of the attachment of the extensor complex.

    Second, he states that the anatomic variation between bone and tendon may be the terminal consequence (expanded via email as the “accident waiting to happen”) in the cause of tennis elbow. If we understand his question, then we agree that these underlying anatomic relationships only lay the foundation for the development of tennis elbow. Another requirement is that the elbow must be moved while the wrist extensors are under tension. If a person with a predisposing anatomic variation never puts his/her elbow/wrist extenesors to substantial use then he/she is unlikely to develop the disorder.

    We found no change in the extent or type of rubbing of tendon on bone due to shoulder position.

    In regard to the last sentence in his first paragraph, our hypothesis is that the tendon is weakened by the transverse rubbing (trauma) of the tendon on bone. Other authors cited in our paper, not us, described tendinous microtears from longitudinal overload as the source of tennis elbows.(1). We propose that once the tendon is weakened, tension plus abrasion causes further damage as occurs in any tendon exposed to attritional wear.

    Reference:

    1. Nirschl RP. Tennis Elbow. Ortho Clinics NA 1973;4:787-800.

    Myron M. LaBan, M.D., MMSc.
    Posted on October 10, 2007
    Anatomic Factors Related to the Cause of Tennis Elbow
    Department of Physical Medicine & Rehabilitation, William Beaumont Hospital, Royal Oak, MI 48073

    To The Editor:

    We read with interest the article by Bunata et al.(1)which called attention to the anatomic relationship of the extensor digitorum brevis and the capitellum as one of the precipitating causes of lateral epicondylitis(“tennis elbow”). This syndrome, like that of carpal tunnel and De Quervains tenosynovitis among others, usually results from “overuse”. As such, form and function are inseparable with respect to pathogenesis.

    But even when controlling for age, job description, speed, and repetition of task, why are some more vulnerable to this injury than others? As a “mechanically induced condition” anatomic variation between bone and tendon may, in-fact, be a terminal consequence rather than the “initial step in the cause of tennis elbow. Remote alterations in proximal as well as distal joint biomechanics acting repetitively on the elbow through an altered kinetic chain may instead be the progenitor of the lateral epicondylitis. In this regard, LaBan, Iyer, and Tamler called attention to the frequent presence of ipsilateral restricted shoulder range of motion, especially internal rotation, in patients presenting with symptoms of tennis elbow(2). As a consequence, excessive wrist flexion is required to compensate for the proximal restricted arc of shoulder internal rotation. The extensor digitorum longus and brevis are two-joint muscles which cross both the elbow and the wrist. As such, they have the capacity under load of functionally reversing their origin insertions from a concentric/shortening to an eccentric/elongating contraction. As the muscles in mid-cycle precipitously reverse their direction, aging muscle with its reduced elastic modulus may not be “fast enough” to absorb the force of recoil. Instead, the shock of this action is primarily absorbed at the origin of the extensor expansion. With repeated trauma tendinous microtears as described by the authors can develop at the lateral epicondyle.

    In the late 19th century, Epicondylitis lateralis humeri was described as a “lesion which is imperfectly recognized, [and] is sure to find a host of wanted remedies”(3). Over a hundred years later, who would argue?

    The author did not receive any outside funding or grants in support of his research for or preparation of this work. Neither he nor a member of his immediate family 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 author, or a member of his immediate family, is affiliated or associated .

    REFERENCES:

    1. Bunata RE, Brown DS, Capelo R. Anatomic factors related to the cause of tennis elbow. J Bone Joint Surg Am. 2007; 89:1955-63.

    2. LaBan, MM, Iyer R, Tamler MS. Occult periarthrosis of the shoulder. A possible progenitor of tennis elbow. Am J Phys Med Rehabil 2005; 84:1-4.

    3. Tennis elbow: Annotations Lancet 1885; 2:772.

    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
    04/16/2014
    GA - Choice Care Occupational Medicine & Orthopaedics
    04/02/2014
    IL - Hinsdale Orthopaedics