Article

During upper limb motor recovery after stroke, the greatest
improvements occur typically in the first 5 weeks poststroke. It is unclear what
patients learn during this early phase of recovery. OBJECTIVE: To investigate the
hypothesis that, early poststroke, patients learn to master the degrees of
freedom in the paretic upper limb as reflected by dissociated shoulder and elbow
movements during reach-to-grasp. METHODS: Thirty-one patients with a first-ever
ischemic stroke were included. Repeated 3-dimensional kinematic measurements were
conducted at 14, 25, 38, 57, 92, and 189 days poststroke. Trunk, shoulder, elbow,
and wrist rotations were measured during a reach-to-grasp task. Using principal
component analysis the longitudinal changes in dissociated upper limb movements
during reach-to-grasp were investigated. Twelve healthy subjects were included
for comparison. RESULTS: The main coordination pattern during reach-to-grasp in
patients with stroke and healthy subjects consisted mostly of horizontal shoulder
adduction and elbow extension. The standard deviation of this main pattern
increased over time, with the largest increase in the first 5 weeks poststroke (F
= 5.5, P < .001), but remained smaller than in healthy individuals. The standard
deviation increased by 0.46 degrees per day between 14 and 38 days and tapered
off to 0.05 degrees per day between 38 and 189 days poststroke. CONCLUSIONS: Our
results suggest that restitution of motor control by dissociation of shoulder and
elbow movements occurs mainly early poststroke. However, compared with healthy
adults, most patients did not achieve fully dissociated upper limb movements at
26 weeks poststroke, suggesting that upper limb motor control after stroke
remains adaptive.

Langue : ANGLAIS