altered muscle strength and architecture influences motor performance in boys with severe...
TRANSCRIPT
Altered muscle strength and architecture influences motor performance in boys with
severe haemophilia and ankle joint haemarthrosis
David Stephensen1,2, Wendy Drechsler1, Oona Scott1
1Human Motor Performance Laboratory, School of Health, Sport & BioscienceUniversity of East London
2Kent Haemophilia Centre, Kent & Canterbury Hospital
Haemophilia Deficiency of factor 8 (haemophilia A) or factor 9 (Haemophilia B /
Christmas disease)
X linked recessive
Presents before 1 year of age
Haemophilia Deficiency of factor 8 (haemophilia A) or factor 9 (Haemophilia B / Christmas disease)
X linked recessive
Presents before 1 year of age
Recurrent frequent spontaneous bleeding intomuscles and joints
Results in chronic disabling arthropathy
Background
Annual bleed frequency of 1-2 bleeds / yr (Feldmen et al. 2006; Manco-Johnson et al. 2007; Gringeri et al. 2011)
Ankle joint is the most common site of bleeding(Stephensen et al. 2009)
Muscles are smaller and weaker than their unaffected peers
(Stephensen et al., 2012)
Alterations in balance and gait when compared to unaffected peers
(Bladen et al. 2007; Stephensen et al. 2009; De Souza et al., 2012)
Aim of the study
Relationship of lateral gastrocnemius muscle architecture to:
Ankle plantar flexor muscle strength
Knee and ankle function
Participants
Typically developing boys
(TD; n = 19)
Haemophilic boys
(H; n = 19)
Age (yrs) 9.86 1.30 10.37 2.11
Body mass (kg) 34.00 7.08 40.47 12.05
BMI (kg/m²) 18.12 3.75 18.18 2.99
Body stature (m) 1.36 0.07 1.47 0.15
Haemophilic boys were receiving prophylactic treatment and had a history of only ankle joint bleeding
Methodology
Muscle architecture Anatomical cross sectional area (ACSA) Thickness (MT) and width (MW) Muscle fascicle length (FL) and pennation angle
(PA)
Isokinetic muscle strength
Three-dimensional joint angles and moments
Three-dimensional joint angles and moments
Three-dimensional joint angles and moments
Initial DoubleSupport
SingleSupport
TerminalDoubleSupport
Swing
Group TD (n=19)
Group H (n=19)
ACSA (mm2) 690.00 ± 126.00 579.00 ± 86.00*** Muscle architecture MT (mm) 17.00 ± 1.50 15.10 ± 2.10**
Maximum (Nm) 41.04 ± 15.41 26.64 ± 13.89** Muscle strength Normalised to body mass (Nm/kg) 1.05 ± 0.30 0.66 ± 0.31***
Gait Initial double support Knee FLEX moment (Nm/kg) 0.52 ± 0.26 0.71 ± 0.30*
Single support Ankle DF angle (º) 14.03 ± 4.18 16.18 ± 3.66* Knee FLEX moment (Nm/kg) 0.56 ± 0.27 0.76 ± 0.31* Knee EXT moment (Nm/kg) -0.17 ± 0.49 0.03 ± 0.17* Maximum GRF (N/kg) 11.63 ± 0.87 12.41 ± 0.42* Minimum GRF (N/kg) 7.24 ± 0.75 6.79 ± 0.85*
Terminal double support Knee EXT moment (Nm/kg) 0.02 ± 0.06 0.05 ± 0.04*
*p<0.05; **p<0.01; ***p<0.005
Results
Group TD (n=19)
Group H (n=19)
ACSA (mm2) 690.00 ± 126.00 579.00 ± 86.00*** Muscle architecture MT (mm) 17.00 ± 1.50 15.10 ± 2.10**
Maximum (Nm) 41.04 ± 15.41 26.64 ± 13.89** Muscle strength Normalised to body mass (Nm/kg) 1.05 ± 0.30 0.66 ± 0.31***
Gait Initial double support Knee FLEX moment (Nm/kg) 0.52 ± 0.26 0.71 ± 0.30*
Single support Ankle DF angle (º) 14.03 ± 4.18 16.18 ± 3.66* Knee FLEX moment (Nm/kg) 0.56 ± 0.27 0.76 ± 0.31* Knee EXT moment (Nm/kg) -0.17 ± 0.49 0.03 ± 0.17* Maximum GRF (N/kg) 11.63 ± 0.87 12.41 ± 0.42* Minimum GRF (N/kg) 7.24 ± 0.75 6.79 ± 0.85*
Terminal double support Knee EXT moment (Nm/kg) 0.02 ± 0.06 0.05 ± 0.04*
*p<0.05; **p<0.01; ***p<0.005
Results
Group TD (n=19)
Group H (n=19)
ACSA (mm2) 690.00 ± 126.00 579.00 ± 86.00*** Muscle architecture MT (mm) 17.00 ± 1.50 15.10 ± 2.10**
Maximum (Nm) 41.04 ± 15.41 26.64 ± 13.89** Muscle strength Normalised to body mass (Nm/kg) 1.05 ± 0.30 0.66 ± 0.31***
Gait Initial double support Knee FLEX moment (Nm/kg) 0.52 ± 0.26 0.71 ± 0.30*
Single support Ankle DF angle (º) 14.03 ± 4.18 16.18 ± 3.66* Knee FLEX moment (Nm/kg) 0.56 ± 0.27 0.76 ± 0.31* Knee EXT moment (Nm/kg) -0.17 ± 0.49 0.03 ± 0.17* Maximum GRF (N/kg) 11.63 ± 0.87 12.41 ± 0.42* Minimum GRF (N/kg) 7.24 ± 0.75 6.79 ± 0.85*
Terminal double support Knee EXT moment (Nm/kg) 0.02 ± 0.06 0.05 ± 0.04*
*p<0.05; **p<0.01; ***p<0.005
Results
5
10
15
20
25
0 20 40 60
Muscle strength (Nm)M
us
cle
th
ick
ne
ss
(m
m)
300
400
500
600
700
800
0 20 40 60
Muscle strength (Nm)
AC
SA
(m
m2)
TD: r = 0.43
H: r = 0.06 TD: r = 0.35
H: r = 0.53
Muscle strength is related to muscle size
0.0
0.5
1.0
1.5
0.00 0.05 0.10Specific muscle torque (Nm/mm
2)
Kn
ee
fle
xio
n m
om
en
t (N
m/k
g)
H: r = -0.61 (p < 0.05)
TD: r = -0.32
0.0
0.5
1.0
1.5
30 40 50 60 70 80
Fascicle length (mm)
Kn
ee
fle
xio
n m
om
en
t (N
m/k
g)
TD: r = 0.24
H: r = -0.58 (p < 0.05)
10
11
12
13
14
15
0 20 40 60
Muscle strength (Nm)
Ma
xim
um
GR
F (
N/k
g)
H: r = -0.59 (p < 0.05)
TD: r = -0.45
-0.1
0.0
0.1
0.2
0.3
0.00 0.05 0.10
Specific muscle torque (Nm/mm2)
An
kle
do
rsif
lex
ion
mo
me
nt
(Nm
/kg
)
0
10
20
30
5 10 15 20 25
Muscle thickness (mm)
An
kle
pla
nta
rfle
xio
n (
0)
TD: r = -0.13
H: r = 0.52(p < 0.05)
TD: r = 0.13
H: r = -0.46(p < 0.05)
Clinical significance
Importance of evaluating muscle function and strength
Ankle plantar flexors are weaker and smaller
Muscle strength and architecture strongly influence gait adaptations
Impacts ankle and knee joint function during weight-bearing phases of walking
