Biomedical Engineering Reference
In-Depth Information
the muscle co-ordination for the wrist joint could be improved in the un-trained
persons after stroke with 10
◦
/s during the wrist tracking. This speed was then
used in a FES-robot assisted wrist training for chronic stroke.
8.4 FES-ROBOT ASSISTED WRIST TRAINING
After the FES-robot system evaluation, we also conducted a preliminary study on
the training effectiveness of the system on persons with chronic stroke. The five
subjects attended the system evaluation, were recruited for a 20-session FES-robot
assisted wrist training one month later. Before the training, clinical assessments
of FMA (shoulder/elbow and wrist/hand), MAS (elbow and wrist), the action
research arm test (ARAT)(Carroll 1965), and the FIM instrument (Keith
et al
. 1987)
were measured. The training intensity was assigned as 3 to 5 sessions per week,
and the whole training program was finished within 7 consecutive weeks. In each
training session, there were 14 wrist tracking trials, and each trial had five wrist
extension/flexion cycles. The experimental setup for the training was same as
that for the evaluation
(
Figure 8.1
)
. The assistive combination from the FES-robot
system was 1:1 for the FES and robot parts (i.e., m1f1, m5f5, m0f0 described in
when both the FES and robot gave support during the tracking. For the 14 tracking
trials in a training session, alternative FES-robot assistance were applied with the
scheme as described in
Figure 8.7
.
Robotic resistances with different resistive
coefficient values (0%, 10%, and 20% of the maximal wrist torque values during
IMVC, with the detailed definition in Eq 5.3,
Chapter 5
) There were totally 7 types
of assistive and resistive combinations, and each of themwas repeated twice in the
training with the first and the last wrist tracking trials had the gain combination
of 0% assistive and 0% resistive. The reason for applying different gain values
in the training was that the subjects could sense some changes in the training,
which motivated them to concentrate on the tracking tasks; meanwhile, verbal
encouragement was also used during the training.
The FES-robot training effects were assessed by the pre- and post- evaluation
of clinical scores, i.e., FMA, MAS, ARAT, and FIM. The FMA mainly measures
Tab l e 8 . 2
The clinical scores measured before and after the FES-robot assisted wrist
training.
FMA
FMA *
MAS
MAS *
ARAT *
FIM
(Shoulder/
(Wrist/
(Elbow)
(Wrist)
Elbow)
Hand)
Pre-Training
19.8
±
5.1
11.2
±
4.2
1.4
±
0.7
1.8
±
0.7
20.1
±
5.1
65.4
±
1.4
Post-Training
22.2
±
4.7
19.7
±
3.7
0.8
±
0.5
0.5
±
0.4
29.3
±
6.5
65.4
±
1.4
The items marked with ”*” showed significant difference after a paired-t-test with
P
<
0.05.
