Biomedical Engineering Reference
In-Depth Information
Tab l e 3 . 2
Walking Parameters According to Neurological Level and Goals of Gait with
Primewalk.
Level of paresis
Gait speed (m/min)
Step length (cm)
cadence
Cervical injury
(
n
=
3
)
7.6
±
7.5
15.8
±
7.6
44.5
±
12.5
Thoracic injury
(
n
=
13
)
11.3
±
7.5
23.7
±
12.2
47.0
±
16.5
Thoracolumbar injury
(
n
=
10
)
18.0
±
8.8
31.2
±
12.8
57.7
±
16.9
indoors without supervision. In the UT group, the majority of patients (75%) did
not require any assistance and as the thoracic level moved caudally more patients
became independent indoors without supervision. In the TL group, only one
out of 15 required any assistance with less than half of remaining 14 requiring
supervision, and 5 of 15 achieving independence outdoors. For patients able
to walk in orthosis without any assistance, the lower the level of neurological
impairment and the higher the degree of gait independence, the greater were
subject was almost comparable with that of patients using HKAFO such as RGO
(Suzuki; (2007)).
We made decision tree to predict gait independence with Primewalk with fol-
lowing procedure. Inhibitory factors that could interfere with achievement of gait
independence were spasticity, involuntary spasms, pain, contracture, weakness of
the upper extremities, and decreased motivation for performing gait exercise. The
effect of each was evaluated as 'present' when it inhibits walking exercise and as
'absent' when it did not inhibit walking exercise. Recursive partitioning was used
to predict the final status of gait expected at the end of walking training in the basis
of age, sex, neurological level, and inhibitory factors. The decision tree for goals
of gait constructed for the subjects is shown in
Fig. 3.5
. The neurological level was
the first decisive factor. In the second step, age was extracted in group C and UT,
whereas decreased motivation was extracted in group TL. In this group, five of
10 patients with high motivation attained the outdoor-independent level, where
all patients with decreased motivation remained at the level of indoor-supervision
or less. The remaining patient stayed at the indoor-assisted level. Among patients
in groups C and UT and under the age of 50, weakness of upper extremities was
a decisive factor in gait independence in addition to the neurological level and the
presence/absence of spasiticity. The coincident ratio between the value predicted
from the decision tree of gait and the value actually observed was 68.9%. These
results provide useful information to medical teams that prescribe orthoses to SCI.
3.4 LIMITATION OF ORTHOSIS AND FUTURE OF ROBOTICS
In the case of any brace, whether a medial or lateral system, the orthotic gait
eliminates the degree of freedom (DOF) of the knee and ankle joints and achieves
