Scientific Articles   |    
A Histological and Immunohistochemical Study of the Subsynovial Connective Tissue in Idiopathic Carpal Tunnel Syndrome
Anke M. Ettema, MD1; Peter C. Amadio, MD1; Chunfeng Zhao, MD1; Lester E. Wold, MD1; Kai-Nan An, PhD1
1 Orthopedic Biomechanics Laboratory, Division of Orthopedic Research (A.M.E., P.C.A., C.Z., and K.-N. An), and Department of Anatomic Pathology (L.E.W.), Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address for P.C. Amadio: amadio.peter@mayo.edu
View Disclosures and Other Information
In support of their research or preparation of this manuscript, one or more of the authors received grants or outside funding from National Institutes of Health (National Institute of Arthritis and Musculoskeletal and Skin Diseases). None of the authors 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, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated.
Investigation performed at Orthopedic Biomechanics Laboratory, Mayo Clinic and Mayo Foundation, Rochester, Minnesota

The Journal of Bone and Joint Surgery, Incorporated
J Bone Joint Surg Am, 2004 Jul 01;86(7):1458-1466
5 Recommendations (Recommend) | 3 Comments | Saved by 3 Users Save Case


Background: The most common histological finding in carpal tunnel syndrome is noninflammatory synovial fibrosis. The accumulated effect of minor injuries is believed to be an important etiologic factor in some cases of carpal tunnel syndrome. We sought evidence of such injuries in the synovial tissue of patients with carpal tunnel syndrome and in cadaver controls.

Methods: We compared synovial specimens from thirty patients who had idiopathic carpal tunnel syndrome with specimens from a control group of ten fresh-frozen cadavers of individuals who had not had an antemortem diagnosis of carpal tunnel syndrome and who met the same exclusion criteria. Analysis included histological and immunohistochemical examination for the distribution of collagen types I, II, III, and VI and transforming growth factor-ß (TGF-ß) RI, RII, and RIII.

Results: Histological examination showed a marked increase in fibroblast density, collagen fiber size, and vascular proliferation in the specimens from the patients compared with the control specimens (p < 0.001). Collagen types I and II were not found in the synovium of either the patients or the controls, but collagen type VI was a major component of both. Collagen type-III fibers were more abundant in the patients than in the controls (p < 0.001). Expression of TGF-ß RI was found in the endothelial cells and fibroblasts in the patient and control specimens, with a marked increase in expression in the fibroblasts of the patients compared with that in the control tissue (p < 0.001).

Conclusions: These findings are similar to those after injury to skin, tendon, and ligament and suggest that patients with idiopathic carpal tunnel syndrome may have sustained an injury to the subsynovial connective tissue.

Clinical Relevance: The changes demonstrated in the subsynovial connective tissue not only could lead to an increase in the volume of the contents in the carpal tunnel but also may alter its material properties, such as compliance and permeability to fluid flows, and vascularity. These changes may, in turn, predispose the subsynovial connective tissue to additional injury and contribute to the elevation in carpal tunnel pressure seen in patients with carpal tunnel syndrome.

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
    Illinois - Hinsdale Orthopaedics
    Oregon - The Center - Orthopedic and Neurosurgical Care and Research
    Connecticut - Yale University School of Medicine