| Abstract | | Introduction: The cutaneous silent period (CSP) is a transient suppression of electromyographic voluntary isometric activity that follows painful electrical stimulation of cutaneous nerves. Standard electromyographic equipment is used for recording the CSP. The values of CSP in the literature vary due to different methods used by investigators. The aim of our study was to establish normal values of CSP and to compare these values to those in the literature. Methods: Mean values and standard deviations of temporal parameters of CSP (onset latency, endpoint and duration of CSP) during voluntary isometric muscle contraction that follows painful electrical stimulation (ES) of cutaneous nerves of the right upper and lower limb were established in 30 healthy volunteers. CSP was recorded from abductor pollicis brevis muscle (APB) after ES of cutaneous nerves on index and little finger; from extensor digitorum communis muscle (EDC) after ES of superficial radial nerve, and from tibialis anterior muscle (TA) after ES of sural nerve. Results: Mean value and standard deviation ( SD) of CSP onset latency detected over APB were 70.9 9.3 ms, duration 55.1 10.0 ms, endpoint 125.5 11.1 ms after ES of cutaneous nerve on index finger, and 71.8 9.0 ms, duration 52.2 8.9 ms, endpoint 123.7 10.1 ms after ES of cutaneous nerve on little finger. CSP onset latency detected over EDC after ES of superficial radial nerve was 63.5 6.3 ms, duration 44.4 5.7 ms, endpoint 107.9 8.5 ms; the CSP onset latency detected over TA after ES of sural nerve was 97.1 8.7 ms, duration 68.1 11.0 ms, endpoint 165.4 12.0 ms. Conclusion: CSP is a simple electromyographic method that can be useful in demonstrating dysfunction of thin slow conducting nerve fibres and cutaneous nociceptive mechanisms in spinal cord lesions. (Abs. trunc. at 2000 ch.)
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| Summary | | Izhodišča: Kožna tiha perioda (KTP) je kratkotrajna prekinitev elektromiografske hotene izometrične mišične kontrakcije, ki sledi neprijetni ali boleči električni stimulaciji kožnega živca. Za detekcijo KTP uporabljamo standardno elektromiografsko opremo. Podatki o vrednostih časovnih parametrov KTP se v literaturi zaradi različnih metod dela razlikujejo, zato je bil cilj raziskave določiti normativne vrednosti za le-te na URI-Soča in jih primerjati s podatki iz literature. Metode: Pri 30 zdravih preiskovancih smo določili srednje vrednosti in standardne odklone za začetek, konec in trajanje KTP med hoteno izometrično mišično kontrakcijo po električni stimulaciji (ES) kožnih živcev na desnem zgornjem in spodnjem udu. Kožno tiho periodo smo detektirali nad kratko abduktorno mišico palca roke (m. abductor pollicis brevis APB) po ES kožnega živca na kazalcu in mezincu, nad skupno ekstenzorno mišico prstov (m. extensor digitorum communis EDC) po ES povrhnjega radialnega živca ter nad sprednjo tibialno mišico (m. tibialis anterior TA) po ES suralnega živca. Rezultati: Srednja vrednost in standardni odklon (SV SD) začetne latence KTP nad mišico APB po ES kožnega živca na kazalcu sta bila 70,9 9,3 ms, trajanje 55,1 10,0 ms, konec 125,5 11,1 ms; po ES kožnega živca na mezincu je bila začetna latenca KTP 71,8 9,0 ms, trajanje 52,2 8,9 ms, konec 123,7 10,1 ms. Nad mišico EDC po ES povrhnjega radialnega živca je bila začetna latenca KTP 63,5 6,3 ms, trajanje 44,4 5,7 ms, konec 107,9 8,5 ms, nad mišico TA po ES suralnega živca pa začetna latenca KTP 97,1 8,7 ms, trajanje 68,1 11,0 ms in konec 165,4 12,0 ms. Zaključek: Metoda določanja KTP je preprosta, uporabna pri preučevanju delovanja tankih živčnih vlaken in kožnih nociceptivnih odgovorov pri okvarah hrbtenjače. (Izvl. skrajšan na 2000 zn.)
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