Objective: To show cortical reorganization in hemiparetic patients with a primary motor cortex (M1) infarct including the precentral knob by using functional magnetic resonance imaging (fMRI).
Design: Case-control.
Setting: Outpatient clinics in the rehabilitation department of a university hospital.
Participants: Two stroke patients and 20 control subjects.
Interventions: By using fMRI, we evaluated the hand motor function of 2 hemiparetic stroke patients, who had made some recovery from complete paralysis of the affected hand, and 20 control subjects.
Main outcome measures: fMRI was performed by using the blood oxygen level-dependent technique at 1.5 T with a standard head coil. The motor task paradigm consisted of hand grasp-release movements.
Results: The contralateral primary sensorimotor cortex was activated by the hand movements of the control subjects and of the unaffected side of the 2 patients. Only the contralateral (infarct side) primary sensory cortex (S1) was activated by the movements of the affected hand of the 2 patients, a result that was not observed in the control subjects or with the unaffected hand in the stroke patients.
Conclusions: The hand motor function associated with the infarcted M1 in our patients was reorganized into the S1. These results suggest cortical reorganization in patients with an M1 infarct.