Electrophysiological assessment of the effect of intrathecal baclofen in spastic children.
OBJECTIVE
To evaluate the effect of intrathecal baclofen in a group of spastic children using electrophysiological procedures described in adults.


METHODS
Six children (aged 1-14 years) with severe spasticity of various aetiologies underwent transcranial magnetic stimulation, H reflex and flexor reflex studies before and after intrathecal injection of baclofen. Ashworth scale was used for clinical evaluation of spasticity.


RESULTS
Motor evoked potentials, present in two patients before baclofen, were preserved after injection. Before baclofen, H reflex was present in 5 patients (H(max)/M(max) from 0.23 to 0.84) and absent in one who had infantile neuroaxonal dystrophy. After baclofen, it was absent in 4 patients and markedly reduced in one. Surface of flexor reflex significantly decreased after baclofen (P=0.01), while threshold significantly increased (P=0.003).


CONCLUSIONS
In spastic children, the action of baclofen on spinal pathways may be quantified by the same electrophysiological procedures as in adults. This approach may contribute to select optimal dosage.
Dachy
B
B
Department of Neurology, CHU Brugmann (ULB), Place Van Gehuchten, 4, B-1020, Brussels, Belgium. bernard.dachy@chu-brugmann.be
Dan
B
B
D000293:Adolescent; D001418:Baclofen / Q000008:administration & dosage*; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation / Q000295:instrumentation; D004576:Electromyography / Q000187:drug effects; D005260:Female; D018755:GABA Agonists / Q000008:administration & dosage*; D006181:H-Reflex / Q000187:drug effects; D006801:Humans; D007223:Infant; D007278:Injections, Spinal; D008280:Magnetics; D008297:Male; D009125:Muscle Relaxants, Central / Q000008:administration & dosage*; D009128:Muscle Spasticity / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D012018:Reflex / Q000187:drug effects; D012684:Sensory Thresholds / Q000187:drug effects; D004561:Transcutaneous Electric Nerve Stimulation; D016896:Treatment Outcome
D018755:GABA Agonists; D009125:Muscle Relaxants, Central; D001418:Baclofen