Effect of repetitive arm cycling following botulinum toxin injection for poststroke spasticity: evidence from FMRI.
OBJECTIVE
Investigations were performed to establish if repetitive arm cycling training enhances the antispastic effect of intramuscular botulinum toxin (BTX) injections in postischemic spastic hemiparesis. Effects on cerebral activation were evaluated by functional magnetic resonance imaging (fMRI).


METHODS
Eight chronic spastic hemisyndrome patients (49 ± 10 years) after middle cerebral artery infarction (5.5 ± 2.7 years) were investigated. BTX was injected into the affected arm twice, 6 months apart. Spasticity was assessed using the Ashworth Scale and range of motion before and 3 months after BTX injections. Images were analyzed using Brain Voyager QX 1.8, and fMRI signal changes were corrected for multiple comparisons.


RESULTS
During passive movements of affected and nonaffected hands, fMRI activity was increased bilaterally in the sensorimotor cortex (MISI), secondary somatosensory areas (SII), and supplementary motor area predominantly in the contralesional hemisphere, compared with the rest. Following repetitive arm cycling, fMRI activity increased further in MISI of the lesioned hemisphere and SII of the contralesional hemisphere. For patients with residual motor activity, treatment-related fMRI activity increases were associated with reduced spasticity; in completely plegic patients, there was no fMRI activity change in SII but increased spasticity after training.


CONCLUSIONS
Increased activity in SII of the contralesional hemisphere and in MISI of the lesioned hemisphere reflect a treatment-induced effect in the paretic arm. It is hypothesized that the increased BOLD activity results from increased afferent information related to the antispastic BTX effect reinforced by training.
Diserens
Karin
K
University Hospital, Lausanne, Switzerland. Karin.Diserens@chuv.ch
Ruegg
Dieter
D
Kleiser
Raimund
R
Hyde
Sandrine
S
Perret
Nicolas
N
Vuadens
Philippe
P
Fornari
Eleonora
E
Vingerhoets
Francois
F
Seitz
Rüdiger J
RJ
D000328:Adult; D018726:Anti-Dyskinesia Agents / Q000008:administration & dosage*; D001132:Arm / Q000503:physiopathology; D001905:Botulinum Toxins / Q000008:administration & dosage*; D002540:Cerebral Cortex / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality; D006225:Hand; D006429:Hemiplegia / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000503:physiopathology / Q000534:rehabilitation*; D007273:Injections, Intramuscular; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009044:Motor Cortex / Q000503:physiopathology; D009068:Movement / Q000187:drug effects*; D009128:Muscle Spasticity / Q000188:drug therapy* / Q000503:physiopathology; D026741:Physical Therapy Modalities; D016059:Range of Motion, Articular / Q000187:drug effects; D020127:Recovery of Function; D013997:Time Factors; D016896:Treatment Outcome
D018726:Anti-Dyskinesia Agents; D001905:Botulinum Toxins