Effects of 660 and 780 nm low-level laser therapy on neuromuscular recovery after crush injury in rat sciatic nerve.

BACKGROUND AND OBJECTIVE: Post-traumatic nerve repair is still a challenge for rehabilitation. It is particularly important to develop clinical protocols to enhance nerve regeneration. The present study investigated the effects of 660 and 780 nm low-level laser therapy (LLLT) using different energy densities (10, 60, and 120 J/cm²) on neuromuscular and functional recovery as well as on matrix metalloproteinase (MMP) activity after crush injury in rat sciatic nerve. MATERIALS AND METHODS: Rats received transcutaneous LLLT irradiation at the lesion site for 10 consecutive days post-injury and were sacrificed 28 days after injury. Both the sciatic nerve and tibialis anterior muscles were analyzed. Nerve analyses consisted of histology (light microscopy) and measurements of myelin, axon, and nerve fiber cross-sectional area (CSA). S-100 labeling was used to identify myelin sheath and Schwann cells. Muscle fiber CSA and zymography were carried out to assess the degree of muscle atrophy and MMP activity, respectively. Statistical significance was set at 5% (P≤0.05). RESULTS: Six hundred sixty nanometer LLLT either using 10 or 60 J/cm² restored muscle fiber, myelin and nerve fiber CSA compared to the normal group (N). Furthermore, it increased MMP-2 activity in nerve and decreased MMP-2 activity in muscle and MMP-9 activity in nerve. In contrast, 780 nm LLLT using 10 J/cm² decreased MMP-9 activity in nerve compared to the crush group (CR) and N; it also restored normal levels of myelin and nerve fiber CSA. Both 60 and 120 J/cm² decreased MMP-2 activity in muscle compared to CR and N. 780 nm did not prevent muscle fiber atrophy. Functional recovery in the irradiated groups did not differ from the non-irradiated CR. CONCLUSION: Data suggest that 660 nm LLLT with low (10 J/cm²) or moderate (60 J/cm²) energy densities is able to accelerate neuromuscular recovery after nerve crush injury in rats.

The effect of supervised and home based exercises on balance in elderly subjects: a randomized controlled trial to prevent falls / O efeito do exercício físico supervisionado e domiciliar sobre o equilíbrio de indivíduos idosos: ensaio clínico randomizado para prevenção de quedas

Abstract Objective: The aim of the present study was to evaluate the influence of a balance training program on the semi-static balance of elderly persons by comparing a supervised group with individual home-based application. Method: A blinded randomized controlled multi-arm trial was conducted. The elderly individuals were randomized into: Supervised Group (SG; n=18); Domiciliary Group (DG; n=20) and Control Group (CG; n=18). The SG and DG participated in twice weekly training sessions for 10 weeks. A posturography evaluation was performed based on velocity, anterior-posterior (AP) and medial-lateral (ML) medial amplitude variables in firm surface with eyes open (FSEO) and closed (FSEC), tandem stance with eyes open (Tandem EO) and closed (Tandem EC), and single-leg stance (SL) situations. Two-way ANOVA and Tukey's post-hoc were used for parametric data, the Friedman and Wilcoxon post-hoc tests were used for intragroup analysis and the Kruskal-Wallis and Mann-Whitney post-hoc tests were used for intergroup analysis. Results: In intergroup analysis, the DG group showed improvement in body sway in the Tandem EC (velocity and medial amplitude AP) and single-leg stance (medial amplitude ML) situations. The SG showed a decline in the Tandem EO situation in all the variables. In intergroup analysis, the DG showed improvement in the FSEO position (medial amplitude ML), in the Tandem EC position (medial velocity ML), and the single-leg stance position (medial amplitude AP and ML). The SG showed improvement in the FSEO position (medial amplitude ML) and the single-leg stance position (medial amplitude AP), but showed a decline in the FSEO (variable medial velocity AP) and Tandem EO position (medial amplitude AP). Conclusion: The exercises were beneficial for the balance of the elderly individuals, with the DG presenting the best results. REBEC: RBR-3S9M65.

Resumo Objetivo: Avaliar o efeito de um programa de treinamento sobre o equilíbrio semiestático de idosos, comparando a forma de aplicação supervisionada em grupo e individual domiciliar. Método: Ensaio clínico cego randomizado controlado com múltiplos braços. Idosos randomizados em Grupo Supervisionado (GS; n=18); Grupo Domiciliar (GD; n=20) e Grupo Controle (GC; n=18). O GS e o GD participaram do treinamento por 10 semanas, duas vezes por semana. O equilíbrio foi avaliado pela posturografia [variáveis velocidade e amplitude média antero-posterior (AP) e médio-lateral (ML)] nas situações: plataforma fixa olhos abertos (PFOA), plataforma fixa olhos fechados (PFOF), tandem olhos abertos (Tandem OA), tandem olhos fechados (Tandem OF) e Unipodal. ANOVA two-way e post-hoc de Tukey foram utilizados nos dados paramétricos, teste de Friedman e post-hoc de Wilcoxon para análise intragrupos e teste de Kruskal-Wallis e post-hoc de Mann-Whitney para análise intergrupos. Resultados: Na análise intragrupo, o GD apresentou melhora na oscilação corporal pós-treinamento nas posições Tandem OF (velocidade e amplitude média AP) e Unipodal (amplitude média ML). O GS apresentou piora na posição Tandem OA em todas as variáveis. Na análise intergrupo, o GD apresentou melhora na posição PFOA (amplitude média ML), Tandem OF (velocidade média ML) e Unipodal (amplitude média AP e ML). Já o GS apresentou melhora na posição PFOA (amplitude média ML) e Unipodal (amplitude média AP), contudo apresentou piora na posição PFOA (variável velocidade média AP) e na Tandem OA (amplitude média AP). Conclusão: Os exercícios proporcionaram benefícios para o equilíbrio dos idosos investigados, embora o GD tenha apresentado os melhores resultados. REBEC: RBR-3S9M65.