Impaired ability to shift weight onto the non-paretic leg in right-cortical brain-damaged patients.
BACKGROUND
: Stroke patients experience postural instability that can impede functional improvements in their gait. However, the precise functions of the dominant and non-dominant hemispheres in controlling static standing posture and weight-bearing remain unclear.


OBJECTIVE
: To investigate differences in balancing ability between right-handed patients with right and left hemispheric lesions.


METHODS
: Weight shifting was quantitatively evaluated to determine the ability of patients to control their balance in a static posture and during conscious weight shifting onto the paretic or non-paretic leg. Participants were enrolled from a consecutive series of stroke patients attending a rehabilitation program (n=49; 31 male, 18 female; mean age 69.3+/-9.4 years). Age-matched normal controls were recruited as volunteers (n=12; 4 male, 8 female; mean age 67.9+/-4.9 years).


RESULTS
: Patients with cortical lesions in the right hemisphere were able to shift less weight onto the non-paretic leg than patients with cortical lesions in the left hemisphere (p<0.05). There were no correlations between the existence of unilateral spatial neglect and the percentage of weight shifted onto the non-paretic leg, static standing posture (r=0.27, p=0.40) or dynamic standing posture (r=-0.37, p=0.24). In contrast, there was a significant correlation between the percentage of weight consciously shifted onto the non-paretic leg and the existence of anosognosia (r=0.74, p=0.006), but not between static standing posture and anosognosia (r=-0.15, p=0.63).


CONCLUSIONS
: Patients with right cortical hemispheric lesions were able to shift less body weight onto their non-paretic leg. These patients should be encouraged to practice shifting their weight towards their non-paretic leg to improve their balance.
Department of Neurology, Nagoya City University Medical School, Mizuho-ku, Nagoya 467-8601, Japan.
Fumiyasu
F
Ishii
Noriyuki
N
Matsukawa
Mitsuya
M
Horiba
Takehiko
T
Yamanaka
Manabu
M
Hattori
Ikuo
I
Wada
Kosei
K
Ojika
D000368:Aged; D002540:Cerebral Cortex / Q000473:pathology*; D002544:Cerebral Infarction / Q000150:complications* / Q000473:pathology*; D015444:Exercise; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006293:Health Promotion; D006801:Humans; D035002:Lower Extremity / Q000503:physiopathology*; D008297:Male; D010291:Paresis / Q000209:etiology* / Q000503:physiopathology*; D011187:Posture; D016474:Weight-Bearing