Low Level Laser Therapy for the Treatment of Tendinopathy With Emphasis on the Achilles Tendon

267 Pages·2010·4.07 MB·English

by  Your Name Here

Low Level Laser Therapy for
the Treatment of Tendinopathy
With Emphasis on the Achilles
Tendon

Steven James Tumilty
Master of Physiotherapy
School of Physiotherapy, University of Otago
Thesis submitted for Doctor of Philosophy (PhD)
2010
Abstract
Low level laser therapy (LLLT) has emerged as a potential treatment option for
tendinopathy. Like other electrotherapy modalities, LLLT is a dose dependant modality,
thus studies are required to refine dosage guidelines, and to determine effectiveness.
Despite evidence from laboratory studies supporting the beneficial effects of LLLT, it still
remains on the fringes of mainstream medicine; in particular, positive results obtained in
the laboratory have not been consistently reproduced in the clinical setting. The review
of the literature undertaken for this thesis highlighted a number of shortcomings in
research to date on LLLT: this includes poor methodology, poor reporting of parameters,
and varying application techniques. Tendinopathy has become the scourge of the
musculoskeletal practitioner because of the nature of the pathogenesis of the condition.
Existing literature indicates that tendinopathy is the result of a failure of one of two
processes: the healing response, or the normal turnover/remodeling response; however,
the definitive solution to the problem remains an enigma. One intervention that is
popular, especially for the Achilles tendon (tendo calcaneus) and patellar tendons, is
heavy load eccentric exercises. Utilizing methodologies from the top two tiers of the
hierarchy of evidence, the thesis investigated the clinical effectiveness of LLLT as an
adjunct to an eccentric exercise protocol to treat Achilles tendinopathy. A systematic
review with meta-analysis of the literature reporting the use of LLLT to treat
tendinopathy was conducted. Twelve studies provided evidence to support the
relationship between positive outcomes and current dosage recommendations.
Subsequently, a pilot study was conducted using the recommended dose (i.e. 810nm,
100mW applied to six points on the tendon for 30s, for a total of 3J per point and 18J per
session) to assess the feasibility of a larger, adequately powered controlled trial.
Although the results of the pilot study were not statistically significant, the active
treatment group did demonstrate superior change scores for both pain, and function
compared to placebo group. Responding to criticism of the parameters used in the pilot
study, power density was altered from 2.375W/cm2 to 100mW/cm2 for the main
randomised controlled trial (RCT). Although participants in the main trial showed
improvements in function scores at 3 months, which were maintained for a further 9
months, there was no difference in change scores between active and placebo groups at
any of the follow-up points. These findings provide additional evidence for the
effectiveness of heavy load eccentric exercises, but suggest that LLLT treatment, used as
an adjunct and at the parameters indicated, provided no additional benefit for
participants in the treatment group. This thesis adds to the evidence surrounding the use
of laser therapy to treat tendinopathy. The need to refine current guidelines concerning
description of parameters and dose has been highlighted by the findings of the pilot and
main RCTs. Another important issue raised, relates to exercise adherence and clinical
effectiveness of the prescribed dose of eccentric exercise. Finally, the complexity of
accurately measuring the effectiveness of physiotherapeutic interventions in the clinical
setting has also been highlighted, and presents challenges for the profession in the
future.

II
Acknowledgements
Without the support of a number of individuals and organisations, the completion
of this thesis would not have been possible. Their help and assistance is gratefully
acknowledged.
I would like to give a special thanks to Professor G.David. Baxter for supplying the
initial impetus that got me started, the ongoing support and supervision during the
process, and for all the extra skills and knowledge that I have acquired due to his
facilitation and mentorship.
I am grateful to my supervisors and advisors: Professor Suzanne McDonough and
Drs Deirdre Hurley-Osing, Joanne Munn, Jeffrey Basford, and J. Haxby Abbott, for all their
hard work, patience, and advice.
My colleagues at the School of Physiotherapy must also share in this
achievement, as without their taking on the extra load to provide me with time to work
on the thesis, I would not now be at this stage.
Finally, the biggest thank you and expression of my gratitude goes to Irene, Emma
and Simon, who are my inspiration.

III
Outputs from Work Conducted During the Thesis
Publications:
 Tumilty S, Munn J, McDonough S, Hurley DA, Basford JR, 7 Baxter GD. (2010) Low
Level Laser Treatment of Tendinopathy: A systematic Review with Meta-Analysis.
Photomedicine and Laser Surgery. 28(1): 3-16.
 Meyer A, Tumilty S, & Baxter GD. (2009) Eccentric Exercise Protocols for Chronic
Non-Insertional Achilles Tendinopathy: How Much is Enough? Scandinavian
Journal of Medicine & Science in Sports. 19: 609-615.
 Tumilty S, Munn J, Abbott JH, McDonough S, Hurley DA, & Baxter GD. (2008) Laser
Therapy in the Treatment of Achilles Tendinopathy: a Pilot Study. Photomedicine
and Laser Surgery. 26(1): 25-30
Conference Presentations:
 Laser Therapy in the Treatment of Achilles Tendinopathy: A Randomized
Controlled Trial.
Laser Florence 2009.
 The Dose That Works: low Level Laser Treatment of Tendinopathy.
Laser Florence 2009.
 The Use of Low Level Laser Therapy in Musculoskeletal Physiotherapy in New
Zealand.
IPTA Congress 2009 Laser Tokyo. (Awarded best presentation)
 Low Level Lasers in Treating Tendinopathy: A systematic Review with Meta-
analysis.
IPTA Congress 2008 NZLaser. Laser Therapy 2008 17(1); 14.
 Laser Therapy in the Treatment of Achilles Tendinopathy: a Pilot Study.
Proceedings of the Southern Physiotherapy Symposium 2007
 Laser Therapy in the Treatment of Achilles Tendinopathy: a Pilot Study.
Laser Florence2007. (Conference abstracts published in Lasers in Medical Science
2008 23(1); 93.). (Awarded best presentation)
IV
List of Abbreviations
ACC: Accident Compensation Corporation
ADAM: a Disintegrin & Metalloproteinase
ADAMTS: a Disintegrin & Metalloproteinase with Thrombospondin Motifs
AGREE: Appraisal of Guidelines Research Evaluation
AMSTAR: Assessment of Multiple Systematic Reviews
ANCOVA: Analysis of Variance (considering co-variants)
ANS: Autonomic Nervous System
AT: Achilles tendon
ATP: Adenosine Triphosphate
CCT: Controlled Clinical Trial
CI: Confidence Interval
CO : Carbon Dioxide
2
Con: Concentric
CTGF: Connective Tissue growth Factor
DASH: Disabilities of the Arm, Shoulder and Hand Questionnaire
DB: David Baxter
V
DH: Deirdre Hurley-Osing
EBM: Evidence Based Medicine
Ecc: Eccentric
ECM: Extracellular Matrix
ESWT: Extracorporeal Shock Wave Therapy
FDA: Food and Drug Administration (USA)
GaAlAs: Gallium-Aluminium-Arsenide
GaAs: Gallium-Arsenide
GTN: Glyceryl-Trinitrate
He-Ne: Helium-Neon
InGaAlP: Indium-Gallium-Aluminium-Phosphate
IGF-I: Insulin like Growth Factor
INIT: Initial
IR: Infrared
ITT: Intention to Treat
J: Joule
JB: Jeffrey Basford
VI
JM: Joanne Munn
Kg: Kilogram
LASER: Light Amplification by Stimulated Emission of Radiation
LED: Light Emitting Diode
LOCF: Last Observation Carried Forward
LLLT: Low Level Laser Therapy
mJ: milliJoules
mm: millimetres
mRNA: messenger Ribonucleic Acid
mW: milliWatts
MCAR: Missing Completely at Random
MCID: Minimal Clinical Important Difference
MHz: MegaHertz
MMP: Matrix Metalloproteinase
MRC: Medical Research Council (UK)
MRI: Magnetic Resonance Imaging
nm: nanometers
VII
NASA: National Aeronautics and Space Administration
NdYAG: Neodymium-Yttrium-Aluminium-Garnet
Nm: Newton meter
NO: Nitric Oxide
NOS: Nitric Oxide Synthases
NPRS: Numeric Pain Rating Scale
NSAID: Non-steroidal Anti-inflammatory Drug
OA: Osteoarthritis
PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-
Analyses
QUORUM: Quality of Reporting of Meta-Analyses
RA: Rheumatoid Arthritis
RCT: Randomised Controlled Trial
REDOX : Reduction-Oxidation Reaction
RNS: Reactive Nitrogen Species
ROC: Receiver Operating Characteristic
ROM: Range of Motion
VIII
ROS: Reactive Oxygen Species
RR: Relative Risk
SD: Standard Deviation
SM: Suzanne McDonough
SPSS: Statistical Package for the Social Sciences
ST: Steve Tumilty
TGF- β-I: Transforming Growth Factor β-I
TIMPS: Tissue Inhibitors of Metalloproteinases
µm: micrometers
US: Ultrasound
UV: Ultraviolet
VAS: Visual Analogue Scale
VISA-A : Victoria Institute of Sport Assessment – Achilles
W: Watts
WALT: World Association of Laser Therapy
WMA: World Medical Association
WMD: Weighted Mean Difference
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Table of Contents
1 Introduction ............................................................................................................ 1
1.1 Low Level Laser Therapy ................................................................................. 2
1.2 Tendinopathy .................................................................................................. 5
1.2.1 The Biomechanical Hypothesis ................................................................ 5
1.2.2 The Biochemical Hypothesis .................................................................... 6
1.3 Treatment of Tendinopathy ............................................................................ 7
1.4 Evidence Based Medicine ................................................................................ 9
1.5 The Problem .................................................................................................. 12
1.6 Aims of the Thesis ......................................................................................... 13
2 Low Level Laser Therapy ....................................................................................... 14
2.1 Historical Perspective .................................................................................... 14
2.2 Characteristics of Laser Light ........................................................................ 18
2.3 Laser Parameters ........................................................................................... 19
2.4 Mechanisms of Action: Cellular Studies ........................................................ 24
2.5 Laboratory Studies of Tendinopathy ............................................................. 29
2.6 Clinical Trials .................................................................................................. 31
2.7 Optimum Dose? ............................................................................................ 33
2.8 Clinical Effectiveness: Current Reviews ........................................................ 34
2.9 Summary ....................................................................................................... 36
3 Tendinopathy: with Emphasis on the Treatment of the Achilles tendon ............ 38
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