Document Detail

Performance and reliability of a variable rate, force/displacement application system.
MedLine Citation:
PMID:  21036280     Owner:  NLM     Status:  MEDLINE    
OBJECTIVE: Spinal manipulation therapy (SMT), an intervention used to treat low back pain, has been demonstrated to affect the stiffness of the spine. To adequately quantify the effects of SMT on stiffness, a device capable of applying specific parameters of manipulation in addition to measuring force-displacement values has been developed previously. Previously developed indentation techniques that quantify stiffness have been modified for novel use in evaluating SMT parameters. The reliability of stiffness measurements performed by the newly adapted device was assessed in this study.
METHODS: Seven springs of varying stiffness were each indented 10 times by a variable rate force/displacement (VRFD) device. Indentations were performed at a rate of 0.5 mm/s to a maximal displacement of 4 mm. The stiffness coefficients for a middle portion of the resulting force-displacement graph and the terminal instantaneous stiffness (stiffness at end displacement) were calculated. The intraclass correlation and confidence interval were calculated for these stiffness measurements to assess device reliability.
RESULTS: Repeated spring stiffness measures yielded an intraclass correlation coefficient value of 1.0. The mean stiffness values had narrow 95% confidence intervals ranging from 0.01 N/mm to 0.06 N/mm and small coefficients of variation.
CONCLUSION: This VRFD device provides highly reliable stiffness measurements in controlled conditions. Although in vivo reliability remains to be established, the results of this study support the use of the VRFD device in future trials investigating the impact of various SMT parameters on spinal stiffness.
Michèle Vaillant; Joel G Pickar; Gregory N Kawchuk
Publication Detail:
Type:  Evaluation Studies; Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of manipulative and physiological therapeutics     Volume:  33     ISSN:  1532-6586     ISO Abbreviation:  J Manipulative Physiol Ther     Publication Date:  2010 Oct 
Date Detail:
Created Date:  2010-11-01     Completed Date:  2011-02-18     Revised Date:  2013-08-13    
Medline Journal Info:
Nlm Unique ID:  7807107     Medline TA:  J Manipulative Physiol Ther     Country:  United States    
Other Details:
Languages:  eng     Pagination:  585-93     Citation Subset:  IM    
Copyright Information:
Copyright © 2010 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.
Graduate Student, University of Alberta, Edmonton, Alberta, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Body Weights and Measures / instrumentation
Chiropractic / methods*
Equipment Design
Manipulation, Spinal / instrumentation*
Observer Variation
Physical Therapy Modalities / instrumentation*
Reproducibility of Results
Stress, Mechanical*
Grant Support

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Manipulation or microdiskectomy for sciatica? A prospective randomized clinical study.
Next Document:  Functional anatomy of human scalene musculature: rotation of the cervical spine.