Hiroyuki Kato1, Masahiro Izumiyama. 1. Neurology, International University of Health and Welfare Hospital, 329-2763 Nasushiobara, Japan. katoh@iuhw.ac.jp.
Abstract
OBJECTIVE: Most rehabilitative interventions following stroke emphasize the improvement of motor deficits but rarely address sensory function and sensorimotor control. We report here a case of cerebral infarction localized to the postcentral gyrus that presented with severe impairment of motor control due to profound proprioceptive sensory loss. We attempted to demonstrate the mechanism for the motor impairment using functional magnetic resonance imaging (fMRI). CASE REPORT: A 70-year-old woman developed abrupt loss of motor control of the right hand, concomitant with the loss of proprioception of the hand. An fMRI was conducted 12 days after stroke onset. Movement of the unaffected hand activated the normal sensorimotor network in the brain, including the contralateral primary sensorimotor cortex, supplementary motor areas, and ipsilateral cerebellum. However, movement of the affected hand activated only the contralateral primary motor cortex and activation of the cerebral sensorimotor network was severely depressed. Diffusion tensor tractography revealed that the corticospinal tracts were intact. Intensive rehabilitation and the use of visual support enabled the patient to live an independent life. CONCLUSION: Loss of motor control may occur even with a normal corticospinal tract when proprioception is severely impaired by dysfunction of the sensorimotor network in the brain.
OBJECTIVE: Most rehabilitative interventions following stroke emphasize the improvement of motor deficits but rarely address sensory function and sensorimotor control. We report here a case of cerebral infarction localized to the postcentral gyrus that presented with severe impairment of motor control due to profound proprioceptive sensory loss. We attempted to demonstrate the mechanism for the motor impairment using functional magnetic resonance imaging (fMRI). CASE REPORT: A 70-year-old woman developed abrupt loss of motor control of the right hand, concomitant with the loss of proprioception of the hand. An fMRI was conducted 12 days after stroke onset. Movement of the unaffected hand activated the normal sensorimotor network in the brain, including the contralateral primary sensorimotor cortex, supplementary motor areas, and ipsilateral cerebellum. However, movement of the affected hand activated only the contralateral primary motor cortex and activation of the cerebral sensorimotor network was severely depressed. Diffusion tensor tractography revealed that the corticospinal tracts were intact. Intensive rehabilitation and the use of visual support enabled the patient to live an independent life. CONCLUSION: Loss of motor control may occur even with a normal corticospinal tract when proprioception is severely impaired by dysfunction of the sensorimotor network in the brain.