title: Temporal profile of the effects of regional anesthesia on the cutaneous reflexes of foot muscles.
abstract: We analyzed the effects of an anesthetic sciatic nerve block on the cutaneomuscular reflex (cMR) and the cutaneous silent period (cSP) of foot muscles, in order to investigate further the type of fibers involved in their generation. In 14 neurologically normal patients with indication for surgical treatment of hallux valgus, we recorded from the extensor digitorum brevis muscle the reflex responses elicited by high-intensity electrical stimulation of the big toe at various time periods, ranging from 0 to 20 min, after ultrasound-guided sciatic nerve popliteal anesthetic block. The first effect was a delay in cSP onset latency, with no changes in end latency. The cMR remained unaltered up to when subjects were no longer able to maintain the contraction. The effects of local anesthetics on peripheral nerves allow for recognition of the different types of fibers contributing to the cMR and the cSP in muscles of the lower limb.
authors.affiliation: Hospital Universitario Lauro Wanderley, João Pessoa, Paraiba, Brazil.
authors.forename: Isabella A
authors.initials: IA
authors.lastname: Mota
authors.forename: João B
authors.initials: JB
authors.lastname: Fernandes
authors.forename: Marcio N
authors.initials: MN
authors.lastname: Cardoso
authors.forename: Xavier
authors.initials: X
authors.lastname: Sala-Blanch
authors.forename: Markus
authors.initials: M
authors.lastname: Kofler
authors.forename: Josep
authors.initials: J
authors.lastname: Valls-Solé
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000779:Anesthetics, Local / Q000494:pharmacology; D004558:Electric Stimulation; D004576:Electromyography; D005260:Female; D005528:Foot; D007839:Functional Laterality / Q000187:drug effects; D006215:Hallux Valgus / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D008619:Mepivacaine / Q000494:pharmacology*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000502:physiology; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D012018:Reflex / Q000187:drug effects* / Q000502:physiology; D012584:Sciatic Nerve / Q000187:drug effects / Q000502:physiology; D012867:Skin / Q000294:innervation*; D013979:Tibial Nerve / Q000187:drug effects / Q000502:physiology
chemical_list: D000779:Anesthetics, Local; D008619:Mepivacaine