The effects of a new FES device (NESS L300) on walking skills in stroke patients with a drop foot

In the Netherlands, every year 30.000 people sustain a cerebrovasular accident
(CVA or stroke). Although a large proportion of these people (approximately
60%) experience partly recovery, irreversible physical impairments remain. An
estimated 20% of strokes result in a drop foot, which is caused by the
inability to (efficiently) activate the muscles that dorsiflex the ankle joint.
While walking, patients with a drop foot tend to drag the foot during the swing
phase (lack of toe clearance), which places them at risk for tripping.
Furthermore, a drop foot usually is part of a general stereotyped walking
pattern of the affected leg, characterized by insufficient knee and hip flexion
during swing. This lack of flexion predominantly causes stroke patients to
experience difficulties when stepping over obstacles, due to insufficient foot
clearance. Recently, a new device, using functional electrical stimulation, has
been developed that enables separate activation of muscles involved in foot
lift. The hypothesis is that the NESS L300 not only effectively lifts the foot
during gait, but that it also reduces the stereotyped movement pattern of the
affected leg. Walking skills are expected to improve on regular, but even more
on irregular terrain. On irregular terrain, the locomotor pattern has to be
adjusted continuously in order not to stumble or fall. These complex gait
skills are essential for independent and safe mobility in daily life. In this
domain of gait skills, the NESS L300 is expected to be superior over
conventional ankle-foot orthoses.

The main goal of this study is to evaluate the effectiveness of the NESS L300
on walking skills, as compared to a conventional ankle-foot orthosis, in stroke
patients with a drop foot.

Patients will be informed about this study by their physiatrists and eligible
patients will be invited to participate. A 30-minute intake visit will be
planned with one of the physiatrists of the department of rehabilitation of the
Radboud University Nijmegen Medical Centre. After inclusion, physical activity
will be monitored during a 7-day period by means of a pedometer. One to 2 weeks
after the intake visit, a L300 system will de provided and adjusted to the
patient. During the consecutive 2 weeks, each patient is given time to adapt to
the system to be able to increase its use up to 6 hours per day. After these 2
weeks, a gait assessment will be scheduled at the mobility lab of the
department of rehabilitation. During this visit, the quality of obstructed and
unobstructed gait skills will be assessed when walking with the NESS L300 and
when walking with a conventional AFO. The use of the L300 will be continued for
another 6 weeks. In week 10 of the study, level of physical activity will be
monitored for a second 7-day period. At the end of week 10 a second gait
assessment will be conducted. During this visit, the quality of obstructed and
unobstructed gait skills will be assessed once more when walking with the NESS
L300 and when walking with a conventional AFO. Finally, the patient*s
satisfaction with the use of the NES L300 will be evaluated. While using the
L300, the patient will be contacted by telephone every week. The patient will
be asked whether he/she experiences any difficulties using the NESS L300 and
whether the daily use has been increased according to schedule. A more
extensive telephone interview will be held in week 3, 4, 5, 7, and 10 of the
study. In this interview the patient will be asked questions on the how many
and which activities are currently being performed using the NESS L300.

Daily use of the NESS L300 during 8 weeks

Burden associated with participation: see under 'Study design'