Muscle fiber conduction velocity and EMG amplitude of the upper trapezius muscle in healthy subjects after low-level laser irradiation: a randomized, double-blind, placebo-controlled, crossover study

Autor(es)

de Mendonca, Fabiana Sarilho ^[1] ; Camillo de Carvalho, Paulo de Tarso ^[1] ; Biasotto-Gonzalez, Daniela Aparecida ^[1] ; Penimpedo Calamita, Simone Aparecida ^[1] ; Fidelis de Paula Gomes, Cid Andre ^[1] ; Amorim, Cesar Ferreira ^[2] ; Fumagalli, Marco Antnio ^[3] ; Politti, Fabiano ^[1]

Afiliação do(s) autor(es)

^[1] Univ Nove de Julho, Phys Therapy Dept, Postgrad Program Rehabil Sci, UNINOVE, Rua Vergueiro 235, Sao Paulo, SP - Brazil

^[2] Univ Cidade So Paulo, Phys Therapy Dept, Postgrad Program Rehabil Sci, Sao Paulo - Brazil

^[3] Fac Amer, Dept Mech Engn, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Medical Science; v. 33, n. 4, p. 737-744, MAY 2018.
• Citações Web of Science: 1

Resumo

Although low-level laser therapy (LLLT) is an important resource for the treatment of non-specific neck pain patients, the dose which presents the greatest therapeutic potential for the treatment of this pathology is still unclear. The present study aimed to evaluate the immediate effect of LLLT on the muscle fiber conduction velocity (MFCV) and electromyographic activity (EMG) of the upper trapezius (UT) muscle in healthy individuals. A total of 20 healthy subjects were enrolled in a randomized, double-blind, crossover study. Active LLLT (820 nm wavelength, 30 mW, energy total 18 J) or placebo LLLT (pLLLT) was delivered on the UT muscle. Each subject was subjected to a single session of active LLLT and pLLLT. Surface electromyography (sEMG) signal of the UT muscle was recorded during five different step contractions of shoulder elevation force (10-30% maximal voluntary contraction) pre- and post-LLLT irradiation. The values of MFCV and sEMG global amplitude (RMSG) were used to calculate the effects of LLLT. The results showed no difference in the MFCV comparing the LLLT and pLLLT groups (F = 0.72 p = 0.39, eta (p) (2) = 0.004). However, a significant difference was observed in the RMSG between the LLLT and pLLLT (F (1,2) = 16.66; P < 0.0001, eta (p) (2) = 0.09). Individuals who received active LLLT presented a significant decrease in RMSG after laser application (F = 61.28; p < 0.0001, eta (p) (2) = 0.43). In conclusion, the 820 nm LLLT, with energy total of 18 J, did not alter the MFCV but significantly reduced the sEMG signal amplitude of the upper trapezius muscle in healthy subjects to a level of up to 30% of maximal voluntary contraction. (AU)

• Processo FAPESP: 13/13839-9 - Avaliação da dor, mobilidade cervical e da atividade eletromiográfica do músculo trapézio em pacientes com cervicalgia inespecífica pré e pós acupuntura: um estudo cross-over, controlado, randomizado cego
• Beneficiário: Fabiano Politti
• Modalidade de apoio: Auxílio à Pesquisa - Regular