Sensorimotor and Gait Training
and (c) treadmill walking at self-paced speed
with hand supported. Balance assessment
was performed for 12 seconds while treadmill
walk was performed for 3 minutes. The timer
was started once the subject had established
their balance or reached their self-paced
speed during walking. If the subject lost
their balance during the task (moved their
feet from the specific points), the trial was
terminated and restarted when they were
able to balance themselves for full 12 seconds.
Muscle activity were expressed in percentage
MVIC and used for the analysis.
Co-contraction index during postural task
and walking was calculated by equation[39];
Co-contraction index = (lower EMG / higher
EMG) × (lower EMG + higher EMG), where
lower EMG is the level of activity in the
less active muscle and higher EMG is the
level of activity in the more active muscle
represented in the normalized RMS value.
This method provided an estimate of the
relative activation of the pair of muscles as
well as the magnitude of co-contraction.
Sample size calculation
The number of subjects was determined by
G. Power 3.15. In a previous study, peroneal
nerve conduction velocity (NCV) in DPN
patients was 36.6±4.1 m/s compared with
42.8±4.1 m/s in healthy controls[8]. Allowing
that DPN patients might improve mean
conduction velocity from 36.6 m/s to 39.7 m/s,
18 patients were required considering two
tailed, alpha level of 0.05 and power (1-beta)
of 0.85 in each group. We assumed a standard
deviation of 4.1 of the response variable.
Total 44 subjects were shown to be necessary
including hypothesized 20% drop out.
Statistical analysis
The normality of distribution of all variables
was verified using Shapiro Wilk test,
skewness and histogram. Non-parametric
test was used for the measures that showed
non-normal distribution. Demographic
characteristics and baseline measures were
compared using independent t-test or Mann
Whitney U test. 2×2 mixed model ANOVA was
used to find out main effect (group effect and
time effect) and time × group interaction.
If the baseline values showed a significant
difference between the groups, then 2×2
mixed ANCOVA was applied taking pre-values
as covariate. All statistical analyses were
carried out using SPSS version 21. Statistical
significance was indicated if p≤0.05 and
confidence interval was set at 95%. Data
are presented as mean±SD unless otherwise
indicated.
Results
Demographic characteristics have been
presented in Table 1. Comparison of
demographic characteristics revealed no
significant difference between the groups
except HbA1c (p=0.017). The between-group
comparison of baseline assessments found
significant difference only for proprioception
in front direction (p=0.029) (Table 2).
Proprioception
Repeated measures ANOVA revealed a
significant time effect for proprioception
in all the four directions (p≤0.016), group
effect was found significant only in the
front direction (p=0.002) and time×group
interaction was found significant for
proprioception in front (p=0.027), back
(p=0.032) and left (p=0.011) directions (Table
3). The intervention group in the present
study showed more improvement in front,
back, left and right direction (31.38%, 32.18%,
47.26%, and 47.42%, respectively) than
control group (19.29%, 2.22%, 0.2%, and
8.89%, respectively).
Current Pedorthics | September-October | January/Feburary 2020
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