AJSM Click here for details!
HOME HELP CONTACT US SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Sign In to gain access to subscriptions and/or personal tools.
First published on June 13, 2007, doi:10.1177/0363546507303115
This version was published on October 1, 2007
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
35/10/1668    most recent
0363546507303115v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Request Reprints
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Näslund, J.
Right arrow Articles by Lindberg, L.-G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Näslund, J.
Right arrow Articles by Lindberg, L.-G.
Related Collections
Right arrow Epidemiology
Right arrow Knee
Right arrow Patella
The American Journal of Sports Medicine 35:1668-1673 (2007)
© 2007 American Orthopaedic Society for Sports Medicine

Decreased Pulsatile Blood Flow in the Patella in Patellofemoral Pain Syndrome

Jan Näslund, PhD{dagger},*, Markus Waldén, MD{ddagger} and Lars-Göran Lindberg, MSc§

From the {dagger} Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden, the {ddagger} Department of Orthopaedics, Hässleholm Hospital, Hässleholm, Sweden, and the § Department of Biomedical Engineering, Linköping University, Linköping, Sweden

* Address correspondence to Jan Näslund, PhD, Nobels väg 8, Stockholm, Sweden, SE-17177 (e-mail: jan.naslund{at}ki.se).

Background: Anterior knee pain without clinical and radiologic abnormalities has primarily been explained from a purely structural view. A recently proposed biologic and homeostatic explanation questions the malalignment theory. No objective measurement of the pathophysiology responsible for changes in local homeostasis has been presented.

Hypothesis: Flexing the knee joint interferes with the perfusion of the patellar bone in patellofemoral pain syndrome.

Study Design: Case control study; Level of evidence, 4.

Methods: Pulsatile blood flow in the patella was measured continuously and noninvasively using photoplethysmography. Measurements were made with the patient in a resting position with knee flexion of 20° and after passive knee flexion to 90°. In total, 22 patients with patellofemoral pain syndrome were examined bilaterally, and 33 subjects with healthy knees served as controls.

Results: The pulsatile blood flow in the patient group decreased after passive knee flexion from 20° to 90° (systematic change in position, or relative position [RP] = –0.32; 95% confidence interval for RP, –0.48 to –0.17), while the response in the control group showed no distinct pattern (RP = 0.17; 95% confidence interval for RP, –0.05 to 0.31). The difference between the groups was significant (P = .0002). The median change in patients was –26% (interquartile range, 37).

Conclusions: Pulsatile patellar blood flow in patellofemoral pain syndrome patients is markedly reduced when the knee is being flexed, which supports the previous notion of an ischemic mechanism involved in the pathogenesis of this pain syndrome.

Key Words: knee • pain • bone • ischemia • photoplethysmography






HOME HELP CONTACT US SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2007 by the American Orthopaedic Society for Sports Medicine.