Changes in postural control in hemiplegic patients after stroke performing a dual task.

Objective: To determine the effects of an attentional task on
hemiplegic patients’ postural control performances.
Design: Retrospective study.
Setting: Department of physical and rehabilitation medicine
at a university hospital.
Participants: Twenty-three hemiplegic patients and 23
healthy age- and sex-matched control subjects.
Interventions: Not applicable.
Main Outcome Measures: Sway area and sway path of the
center of pressure were measured during 30 seconds in standing
subjects and patients under 3 conditions: eyes open (EO),
EO while performing a simple arithmetic task (EO-AT), and
eyes closed (EC).
Results: In the hemiplegic patients, the body sway area
increased significantly with EC (P.001) and during the
EO-AT task (P.017) in comparison with EO. Sway area with
EO-AT remained, however, significantly smaller than with EC
(P.014). In the healthy subjects, the body sway did not differ
significantly between the EO-AT and EO tasks (P.42). The
increase observed in the sway area and path in the hemiplegic
population during the EO-AT task correlated significantly with
age.
Conclusions: The postural performances of hemiplegic patients
decreased during both the arithmetic task and the EC
task. The cognitive task had no effect on healthy subjects’
postural performances. This study is the first to show the
combined effects of age and dual task on the postural performances
of hemiplegic subjects.