SUBJECTS AND METHODS
The participants in this study were fifteen hemiplegic patients who had been diagnosed with stroke (Table 1) who were receiving inpatient or outpatient treatment at hospital P rehabilitation center. The following were the conditions for inclusion in the study. The present study had a single-group pre-post design. All the subjects participated in a four-week six-method hip extensor strengthening exercise (HESE) program. This program was performed by a therapist manipulating the subjects for about half an hour a day in the supine position, side-lying position, and prone position on a treatment table. The HESE program comprised six steps:
1. Hip extension and posterior tilt movement;
2. Rotation extension movement of both the legs;
3. Hip joint and pelvis movement using a therapeutic ball;
4. Hip joint and pelvis movement using a therapeutic ball;
5. Hip joint extension muscle strengthening movement in
the side-lying position; and
6. Hip joint extension muscle strengthening movement in
the prone position.
The program was performed three times a week for four
weeks. Each session consisted of three sets of 15 performances
of the 6-step program lasting about half an hour,
with 30 seconds of relaxation time between the sets11)
. Each
participant was assessed by a physical therapist before and
after the intervention in order to examine its effects on gait
performance and stability. The 10-m walking velocity test
and the Berg Balance Scale (BBS) were used to evaluate the
changes in gait performance and stability. BBS is a widely
used clinical test which was developed to evaluate both
the static and kinetic balance abilities of stroke patients. It
consists of 14 assessment items: sitting to standing, standing
without support, sitting without support, standing to
sitting, transfers, standing with eyes closed, performing the
Romberg test with eyes open, reaching, turning and looking
over the shoulder, making 360° turn to the right and left, and
standing on one leg. Each item is scored from 1 to 5. It has
been shown that subjects with BBS scores >41 have a low
risk of fall, medium risk of fall for BBS scores of 21–40,
and high risk of fall for BBS scores of less than 20. BBS can be used to evaluate the balance ability of patients with
hemiplegia caused either by senile disorder or stroke12)
. A
GAITRite (Gait trainer 2 analysis system, USA) was used to
measure the spatiotemporal variables of gait (walking speed,
walking cycle, affected side stance phase, stride length) and
the symmetry index (stance phase, stride length). Subjects
performed three trials for both pre- and post-test measurements.
When GAITRite was used in the study, it helped
the participants observe in real time their feet touching the
ground on a monitor. GAITRite can compare gait velocity
(meter/sec), gait cycle (cycle/sec), and the symmetry index
(%) of the stance phase and the swing phase, with normal
category values on a histogram13)
. Statistical analyses were
performed using SPSS Version 20.0. The Shapiro-Wilks test
was used to verify the general and medical characteristics
and the measured variables displayed a normal distribution.
The assumption of a normal distribution was confirmed. All
data are presented as mean ± standard error. The chi-square
was used to compare the general and medical characteristics
of the participants and the paired t-test was conducted to
compare the results of before and after the treatment. The
statistical significance level was chosen as α=0.05. The formulas
for the symmetry indexes of the stance phase and stride
length used in the study were: symmetric index of length (%)
= non-affected side low extremity length (cm)/affected side
low extremity length (cm) × 100%; and symmetric index of
the stance phase (%) = affected side low extremity stance
phase (sec)/non-affected side low extremity stance phase
(sec) × 100%. The protocol of this study was approved by
the Committee of Ethics in Research of the University of
Yongin, in accordance with the terms of Resolution 5-1-20,
December 2006. Furthermore, all subjects provided their
informed consent to participation in the present study.