EMG biofeedback-assisted exercises in hemiplegic patients
111
the study. The median time since stroke was 70.5 days
after injection of botulinum toxin in spastic lower ex-
tremity muscles resulted in better reduction in muscle
(range 10–144 days). There were no statistically sig-
nificant differences between the 2 groups considering
tone (13). EMG BF, in combination with conventional
age, sex, time since stroke and hemiplegic side
(Table I).
Table II. Pretreatment; posttreatment, 1 st and 3 rd month results of the
In both groups, all the variables showed signi-
EMG BF and the Sham Groups
ficant improvements after the treatment or after
3 rd month
Pre-treatment
Median
Post-treatment 1 st month
Median
the 1 st and 3 rd month visits with medium and large
(range)
Median (range) Median (range) (range)
effect sizes, except MAS score, which has small
Range of motion
effect sizes for the after treatment, 1 st and 3 rd month
Ankle dorsiflexion angle (active)
visits in the sham group (Table II).
EMG BF
10 (1–40)
15 (5–40)
15 (5–40)
17.5 (5–40)
DISCUSSION
These results indicatae that rehabilitation program-
mes including lower extremity exercises via EMG
BF or sham interventions improved the ROM,
muscle strength, and functional level in hemiplegic
patients with stroke.
Despite the fact that EMG BF has been in use
for years, there is doubt about the efficacy of this
technique. In 1998, a meta-analysis of 8 randomi-
zed controlled trials concluded that EMG BF was
superior to conventional therapy for improving
ankle dorsiflexion muscle strength in stroke pa-
tients (11). A more recent meta-analysis of 13
randomized controlled studies concluded that
EMG BF did not show an additional treatment
benefit over standard physiotherapy (8).
In the above-mentioned meta-analysis, motor
strength, range of motion, gait and functional
parameters were assessed; however, reduction in
muscle tone was not evaluated. It has been pro-
posed that regulation of muscle tone is disrupted
by neuronal damage after stroke and that patients
may have some unaffected pathways that are not
initially obvious (7). With the help of EMG BF,
it may be possible for patients to learn how to
use these preserved pathways, and this control
may result in the recovery of muscle function
(8). EMG BF can be used either to increase the
activity in weak or paretic muscles or to facilitate
a reduction in muscle tone if it is spastic (12). A
recent controlled trial administration of EMG BF
Table I. Demographic characteristics of the groups
Age, years, median
(range)
Stroke duration, days,
median (range)
Sex, female/male, n
(%)
Hemiplegic side, right/
left, n (%)
EMG BF Sham p-value
59 (18–78) 58 (22–71) 0.892
95 (10–444) 68 (10–425) 0.734
6 (35.3)/11(64.7) 6 (35.3)/11(64.7) 1.000
10 (58.8)/7(41.2) 6 (35.3)/11(64.7) 0.169
EMG BF: electromyographic biofeedback.
ES EMG BF
Sham
ES Sham
Knee flexion
EMG BF
ES EMG BF
Sham
ES Sham
–
10 (1–40)
–
angle (active)
100 (60–130)
–
100 (60–130)
–
–1.0
10 (1–40)
–0.7 –0.9
20 (50–40)
–1.4 –1.1
20 (50–40)
–1.3
120 (90–130)
–1.1
100 (60–130)
–0.9 120 (90–130)
–1.4
120 (90–130)
–0.9 120(90–130)
–1.4
120 (90–130)
–1.0
1 (0–2)
0.6
1 (0–3)
0.0 1 (0–2)
0.8
1 (0–3)
0.1 1 (0–2)
0.8
1 (0–3)
0.3
99 (38–308)
–1.1
88 (49–243)
–1.3 121 (41–302)
–1.4
102 (50–258)
–1.3
91 (38–176)
–1.4
71 (23–255)
–1.8 98 (46–178)
–1.6
80 (29–247)
–1.6
23 (9–46)
–1.1
20 (12–39)
–1.6 21 (11–49)
–1.0
30 (16–38)
–2.0
22 (8–35)
–1.6
18 (10–33)
–2.1 20.5 (9–62)
–1.5
20 (12–35)
–2.3
Spasticity
MAS
EMG BF
ES EMG BF
Sham
ES Sham
1 (0–3)
–
1 (0–3)
–
Muscle strength
Knee extension 600 peak torque (N/m)
EMG BF
65 (18–123)
85 (35–229)
ES EMG BF –
–1.0
Sham
52 (24–213)
72.5 (28–240)
ES Sham
–
–1.0
Knee extension 30° peak torque (N/m)
EMG BF
50 (14–121)
72 (32–171)
ES EMG BF –
–1.0
Sham
36 (11–220)
63.5 (24–228)
ES Sham
–
–1.3
Ankle dorsiflexion 15° peak torque (N/m)
EMG BF
8 (1–27)
18 (3–33)
ES EMG BF –
–1.0
Sham
11 (5–24)
16 (8–33)
ES Sham
–
–1.5
Ankle dorsiflexion 0° peak torque (N/m)
EMG BF
5 (1–22)
15 (7–24)
ES EMG BF –
–1.3
Sham
9 (1–28)
14.5 (3–31)
ES Sham
–
–1.4
Mean quadriceps MUP amplitude (µv)
EMG BF
20.4 (8.2–46.1) 32.4 (18.1–69.8)
ES EMG BF –
–1.3
Sham
20.6 (5.7–45) 24.5 (7.1–57.3)
ES Sham
–
–0.5
Mean tibialis anterior MUP amplitude (µv)
EMG BF
12.1 (3.3–46.5) 27.3 (5.8–63.2)
ES EMG BF –
–1.1
Sham
13 (5.1–30.6) 19.3 (10–57.9)
ES Sham
–
Function
Barthel Index
EMG BF
55 (15–95)
ES EMG BF –
Sham
45 (30–85)
ES Sham
–
10 m walking time (s)
EMG BF
25 (13–69
ES EMG BF
–
Sham
30 (15–69)
ES Sham
–
43.7 (14.7–82.6) 42.1 (22–58.6)
–1.3
–1.5
30.6 (11.4–59.8) 49.4 (18–89.6)
–0.8
–1.2
24.3 (8.3–64.9)
–1.0
28.1 (8–43.2)
–0.9 –1.4 26.8 (4–80.9)
–0.9
27.4 (17.7–
38.8)
–1.8
70 (50–100)
–1.0
65 (40–85)
–1.4 75 (50–100)
–1.2
70 (40–85)
–1.5 75 (60–100)
–1.3
70 (40–95)
–1.5
20 (5–62)
0.9
26 (10–68)
1.6 16 (8–53)
1.1
22 (13–60)
1.2 15.5 (9–53)
1.1
20 (10–57)
1.2
MAS: Modified Ashworth Scale; MUP: motor unit potential; ES: effect size; EMG BF:
electromyographic biofeedback.
J Rehabil Med 51, 2019