Cutaneous reflexes from the foot during gait in hereditary spastic paraparesis
Duysens, Jaak × Baken, B C M Burgers, L Plat, F M den Otter, A R Kremer, H P H #
Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology vol:115 issue:5 pages:1057-1062
OBJECTIVE: It is known that P2 cutaneous reflexes from the foot show phase-dependent modulation during gait. The role of the motor cortex and the cortico-spinal tract in these reflexes and their modulation is unknown. Patients with hereditary spastic paraparesis (HSP) have a lesion in the cortico-spinal tract and may show deficits in P2 reflexes and/or their modulation. METHODS: Reflex responses of tibialis anterior and biceps femoris after sural nerve stimulation in 10 HSP-patients were compared with those in 10 healthy subjects. The reflexes were studied at two different moments in the step cycle during walking on a treadmill. RESULTS: Both patients and controls showed a phase-dependent modulation of P2 responses. For the individual muscles, no significant difference in reflex activity was observed between HSP-patients and the controls. However, when all muscles were taken together, the reflex activity for the controls was significantly higher than for the patients. CONCLUSIONS: The results of this study suggest that the cortico-spinal tract is involved in the regulation of the amplitude of the P2 responses and their phase-dependent modulation.