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tional physical therapy (3), or body-weight-supported
locomotor training with manual assistance (11).
Spontaneous improvement after SCI can occur up to
2 years post-injury (12), and, as expected, uncontrolled
studies of training in the early phase after injury show
more recovery of walking function than when training
starts later. Regardless of methodological differences in
the studies, there seems to be consensus that early gait
training in motor incomplete SCI improves walking
function irrespective of the training method (8).
Subjects with incomplete SCI with more severe
functional deficit also seem to benefit from RALT.
However patients without walking function before
training are also frequently unable to walk indepen-
dently after intervention (1, 11, 13).
There are little data available regarding late-onset
training in subjects severely affected by SCI. We
recently published a controlled study on manually as-
sisted weight-supported locomotor training in subjects
with chronic incomplete SCI (2+ years post-injury),
with severely reduced or no walking function (13).
The rationale for the present robot-assisted RCT was
to investigate whether a less personnel-demanding
robot-assisted training programme would have similar
treatment effects as the manually assisted approach in
comparison with control groups receiving usual care.
The 2 studies are parallel in design, outcome assess-
ment and time, but the participants, training site and
staff are different.
METHODS
Recruitment and consent
Compared with our previous study (13), which recruited sub-
jects nationally, subjects in this study were eligible if they lived
within 70 km of the training site. Recruitment occurred either
from Sunnaas Rehabilitation Hospital or through advertisements
in magazines for persons with SCI. Written informed consent
was obtained prior to inclusion. The study was approved by
the Regional Committee of Ethics (REK) in North Norway (P
REK NORD 69/2008 and 2009/634-5) and ClinicalTrials.gov
identifier #NCT00854555.
Inclusion criteria included age 18–70 years, motor incomplete
SCI classified as American Spinal Injury Association (ASIA)
Impairment Scale (AIS) C or D at least 2 years post-injury. Sub-
jects should be mainly wheelchair-dependent with or without
some walking function, have a body mass index (BMI) < 30, and
be cognitively unaffected. Exclusion criteria were conditions
that might prevent or conflict with locomotor training (13) or
physical limitations for using the robotic device.
Setting
Evaluation and testing were completed within 30 days before
randomization, and post-evaluation within 14–30 days after
www.medicaljournals.se/jrm
completion of the intervention/control period. Examiners were
not involved in the training. Subjects were randomized to either
intervention (I) or control group (C) using concealment by
sealed envelopes. The outpatient intervention site was located
in the Oslo area. Assessments were conducted single blindly at
Sunnaas Rehabilitation Hospital. Subjects were instructed to not
change their anti-spasticity medication during the study period.
Training protocol
Intervention subjects received 60 days of RALT, with 3 training
sessions per week over a period of 6 months. The Lokomat®
gait training robot (version 4.0) (HOCOMA, Zürich, Switzer-
land) was used. Each session included preparation (stretching,
fitting harness, etc.) for approximately 20–30 min, stepping
on a treadmill 20–60 min with body-weight support < 40%
of the subject’s initial weight, and, finally, a few minutes of
overground walking and/or exercises on the treadmill if time
permitted. Subjects’ feet and hips were secured to motorized
braces and, during the treadmill walking, the subjects received
continuous feedback on their contribution to the movements.
Computer-controlled motors, synchronized with the speed of
the treadmill, moved the subjects’ legs through trajectories that
imitate physiological gait patterns. One therapist managed the
training session. Progression in the training programme was
defined as a reduction in body-weight support, adjusted guidance
force and/or an increase in walking speed.
Similar to the control group of our manually assisted RCT
(13), control subjects received low-intensity usual care from
their local physical therapist, usually 1–5 times per week. Their
daily activities and training were recorded in a diary that was
submitted once a month. To secure compliance, control subjects
received regular follow-up telephone calls.
The primary outcome was full or partial recovery of walking
function, and there were several secondary outcomes: walking
speed and endurance were assessed using the 10-m walk test
(10MWT) and 6-min walk test (6MWT). Lower extremity mo-
tor score (LEMS), a subscale of ASIA classification, was used
to evaluate strength in the lower limbs. Dynamic balance and
postural control were assessed by Berg’s Balance Scale (BBS)
and the Modified Functional Reach test (MFR), respectively.
All tests have been described in detail elsewhere (13).
Power and statistical analysis
Sample size. Based on our unpublished pilot data and literature
(1, 13), it was estimated that 30 subjects (15 in each group) were
needed to obtain a statistical power of 0.80 with alpha error
0.05 for the outcomes walking speed, endurance and balance.
The main statistical analysis compared mean or median
changes from baseline to final evaluation. The 2 groups were
compared at baseline using χ 2 test/Fisher exact for categorical
variables and independent sample t-test (2-tailed, significance
level p < 0.05) for continuous variables. For non-normally
distributed data, Mann–Whitney test was used. Paired samples
t-test or Wilcoxon signed-rank test were used to analyse changes
within groups. Difference in change between the 2 groups was
assessed using Mann–Whitney test. Effect size was calculated
using correlation coefficient, r, to determine the magnitude of
the treatment effects. All analyses were performed using the
23 rd version of SPSS for Windows (IBM SPSS, Armonk, New
York, USA).