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Table II. Changes in walking speed and walking distance, strength, and balance from baseline to evaluation 2–4 weeks post-intervention/
control period
Intervention group (n = 7)
Variables Baseline (range) Mean change (range) p-value Baseline (range)
10MWT
6MWT
LEMS
BBS
MFR, cm
0.3 (0.1–0.7)
0 (–0.1–0.1)
82.3 (25.0–214.5)
6.6 (–14.0–34.0)
28.4 (14.0–38.0)
5.4 (–1.0–19.0)
18.3 (5.0–37.0)
4.3 (0–10.0)
47.0 (42.0–55.0) –11.0 (–19.0–0)
0.80
0.25
0.03
0.03
0.03
Mean change (range) p-value
0.6 (0.1–1.0)
0.1 (–0.1–0.6)*
170.4 (63.0–390.0) 23.1 (–45.0–43.0)*
27.2 (9.0–47.0)
0.2 (–11.0–7.0)
19.8 (4.0–48.0)
3.2 (–1.0–9.0)
43.0 (20.0–55.0) –2.4 (–14.0–8.0)
0.44
0.59
0.69
0.04
0.28
–0.1
–16.5
5.2
1.1
–8.6
Z p-value r
–0.58
–0.27
–1.40
–0.77
–2.17 0.61
0.84
0.17
0.48
0.03 –0.15
–0.07
0.32
0.18
–0.50
*n = 9; **(Intervention – Control)
10MWT: 10-m walk test; 6MWT: 6-min walk test; LEMS: lower extremity motor score; BBS: Berg’s balance scale; MFR: Modified Functional Reach test. Non-
parametric test used. r: effect size; r = 0.10 small effect; r = 0.30 medium effect; r = 0.50 large effect.
with poor walking function at baseline (9, 14). Our
baseline scores were mostly intermediate, and impro-
ved after RALT, similar to previous findings (3, 4).
Those with higher baseline LEMS, seem to gain most
improvement in walking speed (11). chronic SCI without baseline gait function are able to
regain functional walking (5, 10, 11). However, even
among non-walkers, there appear to be some benefits
of gait training, such as improved VO 2 and neuromus-
cular control (9, 10).
Balance Strengths, weaknesses and limitations
There were poor baseline balance scores with signifi-
cant improvement (4.3 points) in the intervention group
compared with controls (3.2 points). However, postu-
ral control declined, possibly due to training-related
stiffness. In comparison, balance assessed with the
Timed-Up-and-Go test, also improved in 3 small RALT
studies (1, 5, 6). RALT may improve truncus stability,
and even a small improvement here may be important
to a person with poor function in daily life (8, 9). The present study has several strengths: most important
is the usual care control group. A single centre reduces
method variation, and single-blind design diminishes
evaluation bias. Post-injury time > 2 years reduces
spontaneous improvement, allowing a lower number
of subjects.
The main limitations are the slow recruitment and
the drop-out subjects. Thus, the study was statistically
underpowered with a low likelihood of detecting mo-
dest improvements, albeit, large enough to demonstrate
no major gains. The number of eligible subjects was
overestimated. Due to the 2-year post-injury inclusion
requirement, some subjects were well-established in
their life with a disability, and reluctant to invest the
time and effort required. The low number of subjects
recruited resulted in unbalanced baseline characteris-
tics (Table I). For instance, the C-group had a baseline
walking function twice that of the I-group, which may
have attenuated potential positive effects, as could the
fact that the usual care (C-group) had over-ground gait
training in some cases. More intense or longer training
would hardly be tolerated, and furthermore, no rela-
tion was previously found between training dose and
outcome in various gait training protocols (15). Our
experience exemplifies the complexity of this type of
clinical research.
Late-onset robot-assisted locomotor training
Difference in mean change
between the groups** I vs C group
Control group (n = 12)
A recent meta-analysis (8) concludes that gait training
in subjects with injury < 1 year ago (2–4) have better
effects on walking function than studies, such as the
present and others (1, 5–9, 13), conducted years after
injury. In addition, LEMS improves most in subjects
with subacute SCI (3, 4), whereas among subjects with
chronic SCI, only minor improvements are found (1,
11). Cheung et al. (8) argue that neuroplasticity is more
efficient in the acute stage, and repetitive functional
gait training improves muscle activation and facilitates
learning of new walking patterns to a larger degree at
this stage.
Baseline function may be important
It was decided to include subjects with poor baseline
walking function since data on their training effects are
more limited. Mirbagheri et al. (10) found that subjects
with more baseline neuromuscular disturbances were
more likely to have reduced spasticity after RALT.
Based on studies so far, including meta-analyses (8),
the effects of RALT on walking function remain in-
conclusive, and it is still unclear whether subjects with
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Conclusion
In conclusion, the primary goal of re-establishing
walking function was not achieved, and between-group
differences in secondary outcomes were not observed,
except the unexpected decline in postural control
favouring the control group. Small, non-significant
improvements in lower extremity strength and ba-