Sensorimotor and Gait Training
Nasseri et al. [37] . Motor nerve conduction
studies were carried out using RMS Salus 2C
electromyography/NCV machine. For deep
peroneal nerve, an active surface electrode
was placed over the extensor digitorum
brevis (EDB) muscle and the reference
electrode was placed over the tendon of EDB.
Distal stimulation was given at 7-8 cm from
the active electrode between the extensor
digitorum longus and extensor hallucis
longus, and proximal stimulation was given
just below the head of fibula. For tibial nerve,
the active surface electrode was placed over
abductor hallucis and the reference electrode
was placed distally near metatarsal head.
Distal stimulation was given at 9 cm from
active electrode behind and proximal to
medial malleolus, and proximal stimulation
was given slightly laterally to the midline
of popliteal fossa, along the flexor crease
of the knee. Nerve conduction studies are
considered to be the most accurate, reliable
and sensitive measure for peripheral nerve
functions [37] .
Electromyographical assessment
Surface electromyography (EMG) was
used to record muscle activity. Surface
EMG electrodes were placed on the tibialis
anterior, medial gastrocnemius, vastus
latralis and multifidus of right limb. The
disposable bipolar Ag/AgCl surface electrodes
were placed according to the SENIAM
recommendations [38] . The diameter of
electrodes was 10 mm and the inter-electrode
distance was 25 mm. The electrodes were
attached to the skin after shaving and
cleansing the area with alcohol swab.
Maximal voluntary contractions (MVC)
were initially carried out for each muscle
as follows: (a) Tibialis anterior: The subject
was asked to lie supine with the left leg in
full extension and foot restrained in midrange
dorsiflexion. The subject attempted
to dorsiflex the ankle joint against manual
resistance by the investigator, which was
applied at mid-dorsum of the foot. (b) Medial
gastrocnemius: In the same position, with
foot restrained in mid-range plantar flexion,
the ankle of left leg attempted plantar
flexion. Resistance was provided at the
plantar aspect of mid-foot region. (c) Vastus
lateralis: The subject sat upright with knees
flexed at 90°, with the ankle of the left leg
restrained from extending, and attempted to
extend the knee against resistance provided
at just above the ankle joint anteriorly.
(d) Multifidus: The subjects laid prone on
a couch and extended their back against
the resistance provided at scapula by the
investigator. The lower legs were strapped.
In total, three trials of MVC were performed
for 5 seconds of isometric phase. The
subjects were asked to ensure maximum
effort throughout 5 seconds; if not, the MVC
were repeated. Electromyographic data was
collected for 4700-4800 ms after the holding
position started. The mean of 3 trials was
calculated for the analysis. Root mean square
(RMS) value was used for normalization of
the EMG activity during the experimental
procedures.
The electromyographical data were
collected through a custom software and
hardware design [PL3508 Power Lab 8/35
Data Acquisition System with Lab Chart Pro
(AD Instruments, Australia)] at a sampling
frequency of 1000 Hz and band-pass filtered
between 5 and 500Hz. The signals were
analogue/digitally stored on a personal
computer.
Subjects then performed the following tasks:
(a) bilateral stance on unstable balance
board with eyes open; (b) bilateral stance
on unstable balance board with eyes closed;
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