title: Central motor conduction in Hirayama disease.
abstract: The pathogenesis of Hirayama disease is usually attributed to microcirculatory disturbances in the anterior spinal artery territory, leading to segmental anterior horn cell loss and occasional lower limb hyperreflexia. In 7 patients with Hirayama disease, central motor conduction to upper (CMCT-ADM) and lower limbs (CMCT-TA) was evaluated. CMCT-TA was normal in all, but CMCT-ADM was marginally prolonged (8.4 msec, amplitude 0.8 mV) on one side only. Peripheral delay in the upper limbs was found in 2 patients (1 side each) which might be due to fall-out of anterior horn cells. In 2 patients with lower limb hyperreflexia, HM ratio, vibratory inhibition and reciprocal inhibition of soleus H reflex were also normal, suggesting lack of pyramidal dysfunction. Our results do not suggest any pyramidal dysfunction as a cause of lower limb hyperreflexia in Hirayama disease.
authors.affiliation: Department of Neurology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
authors.forename: U K
authors.initials: UK
authors.lastname: Misra
authors.forename: J
authors.initials: J
authors.lastname: Kalita
mesh_terms: D000293:Adolescent; D000328:Adult; D004576:Electromyography; D005121:Extremities / Q000294:innervation; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009134:Muscular Atrophy, Spinal / Q000473:pathology / Q000503:physiopathology*; D009431:Neural Conduction / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013116:Spinal Cord / Q000473:pathology