Scientific Articles   |    
Two Short-Term Outcomes After Instituting a National Regulation Regarding Minimum Procedural Volumes for Total Knee Replacement
Christian Ohmann, PhD1; Pablo Emilio Verde, PhD1; Karl Blum, DrPH2; Burkhard Fischer3; Werner de Cruppé, MD, MPH4; Max Geraedts, PhD, MPH4
1 Coordination Centre for Clinical Trials, Heinrich-Heine University, Moorenstrasse 5, 40225 Düsseldorf, Germany. E-mail address for C. Ohmann: ohmannch@uni-duesseldorf.de
2 German Hospital Institute, Hansaallee 201, 40549 Düsseldorf, Germany
3 National Institute for Quality in Health Care (BQS Bundesgeschäftsstelle Qualitätssicherung gGmbH), Kanzlerstrasse 4, 40472 Düsseldorf, Germany
4 Institute for Health Systems Research, Alfred-Herrhausen-Strasse 50, 58448 Witten, Germany
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 in excess of $10,000 from the German Ministry of Health. 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.

Investigation performed at Heinrich-Heine University, Düsseldorf, and National Institute for Quality in Health Care (BQS), Düsseldorf, Germany

Copyright ©2010 American Society for Journal of Bone and Joint Surgery, Inc.
J Bone Joint Surg Am, 2010 Mar 01;92(3):629-638. doi: 10.2106/JBJS.H.01436
5 Recommendations (Recommend) | 3 Comments | Saved by 3 Users Save Case



Several studies have demonstrated positive relationships between high hospital volume and improved outcome following total knee replacement. To our knowledge, it has not been demonstrated whether improved outcomes are causally determined by selective referral to high-volume hospitals. We therefore evaluated the effect of a national regulation regarding minimum hospital volume for total knee replacement on two short-term outcome parameters.


We performed a comparison of the years before (2004, 2005) and after (2006) the implementation of a national regulation on minimum hospital volume for total knee replacement through a secondary analysis of a national database on the quality of inpatient care in Germany as reflected by the number of cases per hospital and the postoperative rates of wound infection and wound hematoma or secondary hemorrhage.


We analyzed 110,349 cases from 2004, 118,922 cases from 2005, and 125,322 cases from 2006. Implementation of the regulation had a significant effect on the number of cases per hospital. Of the hospitals that had performed one to forty-nine cases in 2005, 35.6% moved to higher-volume categories and 21.2% dropped out in 2006. Multiple logistic regression analysis adjusting for patient characteristics demonstrated risk reductions of 22.5% (odds ratio, 0.775; 95% confidence interval, 0.700 to 0.857) for postoperative wound infection and of 44% (odds ratio, 0.562; 95% confidence interval, 0.531 to 0.596) for wound hematoma or secondary hemorrhage from 2005 to 2006. For wound infection, approximately half of the improvement was attributable to the effects of the minimum-volume regulation. For wound hematoma and secondary hemorrhage, the improvement could not be explained by the minimum-volume regulation.


Implementation of the minimum-volume regulation for total knee replacement resulted in more patients being managed at higher-volume hospitals than expected. Following the implementation of a minimum-volume regulation, effects on two short-term outcome parameters were observed, but definite conclusions could only be made regarding wound infection, with the minimum-volume regulation resulting in a decreased rate of infection.

Level of Evidence: 

Therapeutic Level III. 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

    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
    Georgia - Choice Care Occupational Medicine & Orthopaedics
    Ohio - OhioHealth Research and Innovation Institute (OHRI)
    Pennsylvania - Penn State Milton S. Hershey Medical Center