Caloric stimulation-induced augmentation of H-reflexes in normal subjects, but not in spinal cord-injured patients.
This study examined the effects of ice water caloric stimulation on H-reflex amplitude in normal subjects and three complete spinal cord-injured patients. H-reflexes were obtained by stimulating the tibial nerve at the popliteal fossa and recording the H-response from the gastrocnemius muscle. All normal subjects who experienced nystagmus or vertigo demonstrated significant augmentation in H-reflex amplitude with ice water irrigation of the ear canal. In the three spinal cord-injured patients, there was no significant change of H-reflex with the ice water stimulus. The results suggest that descending tracts in the anterior spinal cord must be functional to demonstrate caloric augmentation of H-reflexes. In patients with spinal cord injury, it may be possible to predict the recovery of motor function using this test together with other clinical signs of neurological function.
D000328:Adult; D002150:Caloric Tests; D005260:Female; D006181:H-Reflex; D006801:Humans; D008297:Male; D009046:Motor Neurons / Q000502:physiology; D009132:Muscles / Q000294:innervation; D009434:Neural Pathways / Q000503:physiopathology; D011379:Prognosis; D012023:Reflex, Monosynaptic; D013116:Spinal Cord / Q000503:physiopathology*; D013119:Spinal Cord Injuries / Q000503:physiopathology*; D013979:Tibial Nerve / Q000503:physiopathology; D014724:Vestibular Function Tests; D014726:Vestibular Nuclei / Q000503:physiopathology*