Calf Muscle Activation Strategies in Healthy and Injured Achilles Tendon Conditions

99 Pages·2015·2.72 MB·English

by  Masood, Tahir

STUDIES IN SPORT, PHYSICAL EDUCATION AND HEALTH
222
TJeanhniri KMualsmooadla
Calf Muscle Activation Strategies in
Healthy and Injured Achilles Tendon
Conditions
STUDIES IN SPORT, PHYSICAL EDUCATION AND HEALTH 222
Tahir Masood
Calf Muscle Activation Strategies in
Healthy and Injured Achilles Tendon
Conditions
Esitetään Jyväskylän yliopiston liikuntatieteellisen tiedekunnan suostumuksella
julkisesti tarkastettavaksi yliopiston Liikunnan salissa L304
toukokuun 12. päivänä 2015 kello 12.
Academic dissertation to be publicly discussed, by permission of
the Faculty of Sport and Health Sciences of the University of Jyväskylä,
in building Liikunta, auditorium L304, on May 12, 2015 at 12 o’clock noon.
UNIVERSITY OF JYVÄSKYLÄ
JYVÄSKYLÄ 2015
Calf Muscle Activation Strategies in
Healthy and Injured Achilles Tendon
Conditions
STUDIES IN SPORT, PHYSICAL EDUCATION AND HEALTH 222
Tahir Masood
Calf Muscle Activation Strategies in
Healthy and Injured Achilles Tendon
Conditions
UNIVERSITY OF JYVÄSKYLÄ
JYVÄSKYLÄ 2015
Editors
Taija Juutinen
Department of Biology of Physical Activity, University of Jyväskylä
Pekka Olsbo, Timo Hautala
Publishing Unit, University Library of Jyväskylä
URN:ISBN:978-951-39-6168-8
ISBN 978-951-39-6168-8 (PDF)
ISBN 978-951-39-6167-1 (nid.)
ISSN 0356-1070
Copyright © 2015, by University of Jyväskylä
Jyväskylä University Printing House, Jyväskylä 2015
To the loving memories of my father (Abdul Haque: 1950 – 2014)

&

My mother (Sughra Begum: 1954 – 2015)
ABSTRACT
Masood, Tahir
Calf Muscle Activation Strategies in Healthy and Injured Achilles Tendon
Conditions.
Jyväskylä: University of Jyväskylä, 2015, (cid:28)(cid:20) p.
(Studies in Sport, Physical Education and Health)
ISSN 0356-1070; 222)
ISBN 978-951-39-6167-1 (nid.)
ISBN 978-951-39-6168-8 (PDF)

Achilles tendon transmits triceps surae muscle force to the foot and is one of the
strongest tendons in human body. Despite its strength, it is not immune to injuries
leading to disruption of normal calf muscle activation strategies and leg function.
The objective of this series of studies was to investigate 1) plantarflexor muscle use
during submaximal isometric plantarflexion contractions, 2) electrical and
metabolic activity patterns of superficial and deep ankle plantarflexors in Achilles
tendinopathy and Achilles tendon rupture, and 3) effects of eccentric calf
myotendon rehabilitation on skeletal myotendon glucose uptake and myoelectric
activity patterns of ankle plantarflexors. Isometric plantarflexion force, surface
electromyography and positron emission tomography measurements were
performed on 19 - 35 year old subjects and both longitudinal and cross-sectional
study designs were used. Myoelectric activity and myotendon glucose uptake
during submaximal isometric plantarflexion were quantified at baseline, and after
eccentric rehabilitation in Achilles tendon injury patients. Results indicated that in
healthy individuals the triceps surae accounted for 70% and 80% of cumulative
myoelectric and metabolic activities respectively. Additionally, although muscle
glucose uptake was similar to healthy controls, myoelectric activity of soleus was
greater in the symptomatic leg of the Achilles tendinopathy patients. Similarly,
Achilles tendon glucose uptake in both legs of the tendinopathy patients was
higher than that of healthy controls. The significant reduction in the maximal
plantarflexion force caused by Achilles tendinopathy was eliminated by 12 weeks
of heavy-load eccentric rehabilitation. Furthermore, the rehabilitation caused a
greater glucose uptake in both soleus and lateral gastrocnemius of the symptomatic
leg, while medial gastrocnemius and flexor hallucis longus had higher uptake in
the asymptomatic leg. Conversely, the Achilles tendon glucose uptake was not
affected by eccentric rehabilitation. Regarding electro-myography, significant rise
in the activity of lateral gastrocnemius was evident after the rehabilitation.
Eccentric rehabilitation was also effective in reducing self-reported severity of
Achilles tendinopathy. In the Achilles tendon rupture patient, all plantarflexors
and Achilles tendon displayed substantially higher glucose uptake than in the
control subject followed by considerable reduction due to eccentric rehabilitation.

Keywords: Myoelectric activity, glucose uptake, surface electromyography,
positron emission tomography, eccentric rehabilitation, isometric force.
Author’s address Tahir Masood
Department of Biology of Physical Activity
University of Jyväskylä
P.O. Box 35
40014 University of Jyväskylä
Finland
[email protected]

Supervisors Professor Taija Juutinen Finni, PhD
Department of Biology of Physical Activity
University of Jyväskylä
Finland

Adjunct Professor Kari K. Kalliokoski, PhD
University of Turku,
Turku PET Centre,
Finland

Reviewers Professor Kornelia Kulig, PhD, PT, FAPTA
Division of Biokinesiology and Physical Therapy
University of Southern California
USA

Professor Nicola Maffulli, PhD, MD
Queen Mary University of London, UK
University of Salerno, Italy

Opponent Professor Anton Arndt, PhD
The Swedish School of Sport and Health Sciences
Stockholm, Sweden
ACKNOWLEDGEMENTS
Where to start? Years ago when I got enrolled in the PhD program, I noticed in
the ‘acknowledgement’ section of my supervisor’s PhD dissertation a note of
gratitude for a professor for recommending her for PhD. The same professor,
after 10 years or so, recommended me for postgraduate studies to her. Hence, I
owe Professor Janne Avela two-fold thanks and appreciation. Surely, my grati-
tude towards you does not end there.
I would like to sincerely thank my academic supervisor and mentor Pro-
fessor Taija Juutinen Finni for not only providing me the chance to undertake
this PhD project but also her endless and persistent support ever since. I also
wish to extend my gratitude to Dr. Kari Kalliokoski – my co-supervisor – for
both arranging and guiding through the measurements at Turku PET Centre
and counseling throughout my years as a doctoral student. This study would
never be the same without your valuable contributions. Additionally, I would
like to use this opportunity to cordially thank researchers whose names ap-
peared as coauthors in our joint publications. These include, in addition to my
supervisors, Professor S. Peter Magnusson (Denmark), Professor Jens Bojsen-
Møller (Norway), Dr. Ville Äärimaa (Finland), and Ms. Anna Kirjavainen (Fin-
land). I am also very grateful to Professors Kornelia Kulig and Nicola Maffulli
for their precious time and effort in reviewing this thesis as part of preliminary
external evaluation.
In addition, I would like to document my appreciation for the students
who had assisted me with data collection one way or the other. I wish to espe-
cially thank Ms. Riina Flink and Mr. Pasi Vainio for their help with recruiting
the study subjects and accompanying me on my journeys to Turku for the
measurements. Further, I want to acknowledge the hard work of people whose
names seldom appear in a research journal but without whom virtually no sci-
entific research can be conducted. These are the technicians who work in the
background to help data collection accomplished smoothly. Therefore I would
like to thank everyone at the Neuromuscular Research Center, University of
Jyväskylä and Turku PET Centre for their kind and generous assistance with
the technical and logistical sides of the things as well as for their social and
moral support.
No modern scientific research can be carried out without someone taking
care of the finances. I would like to thank University of Jyväskylä and National
Doctoral Programme of Musculoskeletal Disorders and Biomaterials for the fi-
nancial support they provided during the project.
Last but not the least, I am really indebted to my family, especially my
mother and late father, for their selfless support and encouragement through-
out my busy years away from the sweet home.

Sargodha, March 2015
Tahir Masood
LIST OF ABBREVIATIONS
[18F]-FDG [18F]-fluorodeoxyglucose
μmol Micromole
3-D fmMRI three-dimensional muscle functional magnetic resonance imaging
ADC Analog-to-digital converter
AMPK Adenosine monophosphate-activated protein kinase
AOFAS American orthopaedic foot and ankle society
AT Achilles tendon
ATR Achilles tendon rupture
CED Cambridge electronic design
CTRL Control subjects
dB Decibel
DC Direct current
EMG Electromyography
EMG Electromyography during the maximal isometric contraction effort
MVIC
ES Effect size
FHL Flexor hallucis longus
FUR Fractional uptake rate
GLUT1 Glucose transporter type 1
GLUT4 Glucose transporter type 4
GU Glucose uptake
IED Inter-electrode distance
ISEK International society of electrophysiology and kinesiology
LC Lumped constant
LG Lateral gastrocnemius
MC-SEMG Multi channel surface electromyography
MG Medial gastrocnemius
MPF Median power frequency
MRI Magnetic resonance imaging
mRNA Messenger ribonucleic acid
MVIC Maximal voluntary isometric contraction
n Number of subjects
Na22 An isotope of natrium (sodium)
NF-(cid:459)B Nuclear factor kappa-light-chain-enhancer of activated B cells
NO-PAIN Asymptomatic leg
OPER Operated leg
PAIN Symptomatic leg
RCT Randomized controlled trial
PET Positron emission tomography
RMS Root mean square
ROI Region of interest
SD Standard deviation
SEMG Surface electromyography