Article

Upper limb (UL) poststroke hemiparesis commonly leads to chronic
disability. Despite moderate-to-good clinical recovery, many patients with UL
hemiparesis still do not fully use their arm in daily tasks. Decreased arm use
may be related to deficits in performance of more complex movement than what is
usually assessed clinically. OBJECTIVE: To identify differences between
poststroke and nondisabled control subjects in making complex corrective
movements to avoid an obstacle in the reaching path.
METHODS: Subjects rapidly
reached for a juice bottle on a refrigerator shelf with their hemiparetic or
dominant (controls) arm viewed in a large-screen projected 3D virtual
environment. In random trials, a sliding door partially obstructed the reaching
path. A successful trial was one in which subjects touched the bottle without
their arm or hand hitting the door. RESULTS: Fewer participants with stroke (12%)
were successful at a 65% success rate in avoiding the door compared to controls
(42%). Subjects with stroke also initiated corrections later (further) in the
reaching path (100.7 +/- 77.6 mm) compared to controls (51.6 +/- 31.0 mm)
resulting in a reduced margin of error. While both groups used similar endpoint
movement strategies for obstructed reaching, subjects with stroke used less elbow
and more trunk movement. Participants who reported being more confident using
their hemiparetic arm had higher success rates. CONCLUSION: Arm movement deficits
can be identified when complex tasks are evaluated. Deficits in higher-order
motor function such as obstacle avoidance behavior may decrease actual arm use in
individuals with mild-to-moderate hemiparesis and should be evaluated in routine
clinical practice.

Langue : ANGLAIS