Article

Persons with stroke and hemiparesis walk with a characteristic
pattern of spatial and temporal asymmetry that is resistant to most traditional
interventions. It was recently shown in nondisabled persons that the degree of
walking symmetry can be readily altered via locomotor adaptation. However, it is
unclear whether stroke-related brain damage affects the ability to adapt spatial
or temporal gait symmetry. OBJECTIVE: Determine whether locomotor adaptation to a
novel swing phase perturbation is impaired in persons with chronic stroke and
hemiparesis. METHODS: Participants with ischemic stroke (14) and nondisabled
controls (12) walked on a treadmill before, during, and after adaptation to a
unilateral perturbing weight that resisted forward leg movement. Leg kinematics
were measured bilaterally, including step length and single-limb support (SLS)
time symmetry, limb angle center of oscillation, and interlimb phasing, and
magnitude of "initial" and "late" locomotor adaptation rates were determined.
RESULTS: All participants had similar magnitudes of adaptation and similar
initial adaptation rates both spatially and temporally. All 14 participants with
stroke and baseline asymmetry temporarily walked with improved SLS time symmetry
after adaptation. However, late adaptation rates poststroke were decreased (took
more strides to achieve adaptation) compared with controls. CONCLUSIONS: Mild to
moderate hemiparesis does not interfere with the initial acquisition of novel
symmetrical gait patterns in both the spatial and temporal domains, though it
does disrupt the rate at which "late" adaptive changes are produced. Impairment
of the late, slow phase of learning may be an important rehabilitation
consideration in this patient population.

Langue : ANGLAIS