Postural stability of elderly submmitted to multisensorial physical therapy intervention.

The present study investigated the influence of a regular Physical Therapy program with emphasis on proprioceptive stimulation, on the center pressure trajectory and muscle adjustments necessary to maintain balance on orthostatic position. After medical assessment, 29 subjects (63.06 +/- 2.84 years) were submitted to electromyographic and baropodometric evaluation and, subsequently, to a program of 12 weeks of physical therapy intervention focusing on proprioceptive stimulation. The oscillation of the pressure center (Pressure platform-MatScanTekscan) was evaluated concomitantly to electromyographic signal envelopment and median frequency assessment of anterior tibial and gastrocnemius muscles (signal conditioner module--MCS 1000-V2-LYNX ). The Wilcoxon test was used for comparison of means, with the significance level of 5%. The pressure center trajectory unipodal position with open eyes (UO) decreased significantly after physical therapy intervention. In this position, there was a reduction of the electromyographic signal envelopment and an increase on median frequency of the gastrocnemius muscle, while the anterior tibial muscle showed increased median frequency after intervention. For the unipodal position with closed eyes (UC), the anterior tibial muscle showed significant electromyographic signal envelopment decrease and increase of median frequency, which also increased for the gastrocnemius muscle. It is concluded that the physical therapy intervention promoted decrease of body oscillation, recruitment improvement and adjustment of the gastrocnemius and anterior tibial muscles, contributing to the postural balance improvement in orthostatic position on senior population.

[Peripheral nerve regeneration in mice exposed to an enriched environment]. / Regeneración nerviosa periférica en ratones expuestos a un ambiente enriquecido.

INTRODUCTION: Taking into account the fact that the literature contains no studies on how an enriched environment influences peripheral nerve lesions, in this study we analysed the characteristics of the sciatic nerve in mice submitted to axonotmesis and subsequent exposure to an enriched environment. MATERIALS AND METHODS: Twenty-four male Wistar mice (198.66 +/- 11.61 g) were distributed into the following groups: control, lesion, enriched environment grouping (EEG) and simple environment grouping (SEG). Following lesion to the nerve, the animals were placed in different cages according to the groups they had been allocated to. The enriched cage had an exercise wheel, a ladder, a ramp, and mobile food and water compartments, which were randomly changed every day. After 24 days, the sciatic nerve was analysed quantitatively, morphometrically and functionally. RESULTS: The number of axons in the EEG and SEG groups was higher than that of the control group (p < 0.05). The SEG group had a higher number of axons than the lesion and EEG groups. The diameter of the axons in the experimental groups was smaller than that of the control group. The same occurred with the diameter of the nerve fibre. The thickness of the myelin sheath was inferior in the experimental groups compared to the control, and the value for the SEG group was lower than for the lesion group. The G ratio did not differ among groups. There were no differences in the values of the sciatic function index among the groups, while in the intragroup comparison there was a difference between postoperative days 7 and 14 and the preoperative values. Functioning was restored at postoperative day 21. CONCLUSIONS: The enriched environment did not have a negative effect on axonal regeneration and maturation, but neither did it favour the process. Functional recovery was not influenced by this form of intervention.

Exercício imediato versus tardio na regeneração do nervo isquiático de ratos após axoniotmese: análise histomorfométrica e funcional / Immediate versus later exercises for rat sciatic nerve regeneration after axonotmesis: histomorphometric and functional analyses

OBJETIVO: Devido à controvérsia sobre o melhor momento para iniciar o exercício físico, bem como sua influência sobre a regeneração nervosa periférica, este estudo realizou uma análise histomorfométrica e funcional para avaliar a influência do exercício físico em esteira, aplicado nas fases imediata e tardia da regeneração do nervo isquiático de ratos, após axoniotmese. MÉTODOS: Vinte ratos Wistar machos (229,05±18,02g) foram divididos nos grupos: controle (CON); desnervado (D); desnervado+exercício+gaiola (DEG) e desnervado+ gaiola+exercício (DGE). Após 24 horas da axoniotmese, o grupo DEG iniciou o exercício, enquanto o grupo DGE iniciou no 14º dia, com o seguinte protocolo: velocidade=8m/min, inclinação=0 por cento, 30min/dia, durante 14 dias. Em seguida, a porção distal do nervo isquiático foi retirada para análise histomorfométrica. Realizou-se o registro da marcha (pré-operatório e 7º, 14º, 21º, 28º dias pós-operatório (PO)), através do índice funcional do ciático (IFC). RESULTADOS: O número de axônios regenerados nos grupos D foi maior que no CON (p<0,05), não havendo diferença intergrupos D. O diâmetro do axônio do grupo DGE foi maior que do grupo D, enquanto os demais parâmetros morfométricos apenas apresentaram diferença significativa com o grupo CON. Não houve diferença nos valores de IFC intergrupos, enquanto na comparação intragrupos, o 7º e o 14º dias diferem do pré-operatório, 21º e o 28º dias PO. CONCLUSÕES: O protocolo de exercício em esteira aplicado nas fases imediata e tardia, não influenciou o brotamento axonal, o grau de maturação das fibras regeneradas e nem a funcionalidade dos músculos reinervados.

OBJECTIVE: Considering the controversies regarding the best period to begin physical exercise in relation to peripheral nerve regeneration, along with its influence on regeneration, this study accomplished a histomorphometric and functional analysis to evaluate the influence of physical exercise on a treadmill, applied to the immediate and late stages of sciatic nerve regeneration in rats following crushing injury. METHODS: Twenty male Wistar rats (229.05±18.02g) were divided into the following groups: control (CON); denervated (D); denervated+exercise+cage (DEC) and denervated+cage+exercise (DCE). The DEC group started the exercise 24 hours after the nerve injury, while the DCE group started on the 14th day after the injury, with the following protocol: speed=8m/min, inclination=0 percent, 30min/day, for 14 days. The distal segment of the sciatic nerve was then removed for histomorphometric analysis. The gait was recorded before the operation and on the 7th, 14th, 21st and 28th days after the operation, using the sciatic functional index (SFI). RESULTS: The number of regenerated axons in the D groups was greater than in the CON group (p<0.05), without differences between the D groups. The axon diameter in the DCE group was greater than the diameter in the D group, whereas the other morphometric parameters only showed significant differences with the CON group. There was no difference in SFI values between the groups, whereas within the groups, the 7th and 14th days differed from the values before the operation and on the 21st and 28th days after the operation. CONCLUSIONS: The treadmill exercise protocol that was applied to the immediate and late stages of nerve regeneration did not influence the axonal budding, the degree of maturation of the regenerated nerve fibers or the functional performance of the reinnervated muscles.

[Electrical stimulation and swimming in the acute phase of axonotmesis: their influence on nerve regeneration and functional recovery]. / Estimulación eléctrica y natación en la fase aguda de la axonotmesis: influencia sobre la regeneración nerviosa y la recuperación funcional.

INTRODUCTION: Little attention has been given to the influence of low-frequency phasic electrical stimulation (LFPES) and physical exercise on the quality of peripheral nerve regeneration and functional recovery. AIM. To evaluate the influence of LFPES, swimming and the association between the two in terms of the morphology of the regenerated sciatic nerve following axonotmesis. MATERIALS AND METHODS: Thirty Wistar mice (222.05 +/- 42.2 g) were distributed into groups: control (C), denervated (D), denervated + swimming (DS), denervated + electrostimulation (DE) and denervated + swimming + electrostimulation (DSE). After 24 hours of axonotmesis, the soleus muscle of the DE and DSE groups was stimulated electrically. The DS and DSE groups swam over a period of 22 days. The number of axons, morphometric data on the nerve and the functional index of the sciatic nerve (FIS) were evaluated. RESULTS: The number of axons in the denervated groups was higher than in the control group, and in the DE group the figure was higher than in the D group. The axonal diameter was smaller in the denervated groups, yet in the DS group it was higher than in the D group. The other morphometric parameters were quite similar to those of the C group. The FIS between days 7 and 14 of the post-operative period was different to the pre-operative index and that measured on day 21 of the post-operative period; the DSE group, however, differed from the pre-operative values. CONCLUSIONS: Swimming and LFPES, applied on an individual basis, do not affect the maturation of the regenerated fibres or functional recovery. LFPES favoured axonal regeneration and combining the treatments delayed functional recovery without having any influence on nerve regeneration.

O efeito do intervalo da estimulação elétrica no músculo desnervado de rato / The effect of time interval between electrical stimulation on the denervated rat muscle

OBJETIVO: Comparar o efeito da estimulação elétrica (EE) aplicada diariamente e em dias alternados na densidade de área do tecido conjuntivo (TC) e na área de secção transversa (AST) das fibras do músculo desnervado. MATERIAIS E MÉTODOS: Trinta e cinco ratos foram divididos em grupos controle (C), desnervado (D), desnervado + eletroestimulado diariamente (EED) e desnervado + eletroestimulado em dias alternados (EEA). A aplicação da EE no músculo gastrocnêmio teve início 24 horas após lesão nervosa do tipo axoniotmese, sendo a mesma aplicada durante 20 e 30 dias. Cortes transversais foram corados com HE para mensurações da AST e densidade de área de TC. Análise estatística: teste Shapiro Wilk, seguido pela análise de variância (ANOVA) F (one-way) e teste de Tukey (5 por cento). RESULTADOS: Na análise da densidade de área do TC, observou-se que somente o Grupo EED apresentou valores similares ao Grupo C nos dois períodos analisados. No Grupo 20 dias, não houve diferença na AST quando comparados os grupos submetidos à EE com o Grupo D (p> 0,05), e após 30 dias todos os grupos experimentais alcançaram valores similares ao Grupo C. CONCLUSÕES: A EE não foi eficiente para minimizar a atrofia das fibras musculares. Entretanto, o TC foi responsivo à EE, sendo a aplicação diária mais benéfica ao músculo do que a aplicação em dias alternados, sugerindo que o intervalo de aplicação da EE em músculo desnervado é variável importante para as adaptações do TC.

OBJECTIVE: To compare the effect of electrical stimulation (ES) applied daily and on alternate days, on the area density of the connective tissue (CT) and on the cross-sectional area (CSA) of the denervated muscle fibers. METHODS: Thirty-five rats were divided into the following groups: control (C), denervated (D), denervated + daily electrical stimulation (D+DES) and denervated + alternate-day electrical stimulation (D+ES). The application of ES on the gastrocnemius was started 24 hours after nerve damage of axonotmesis type and was applied for 20 and 30 days. Cross-sections were stained with hematoxylin-eosin to measure the CSA and area density of CT. The statistical analysis consisted of the Shapiro Wilk test followed by analysis of variance (ANOVA) F (one-way) and the Tukey test (p< 0.05). RESULTS: Analysis of the area density of CT showed that only the D+DES Group presented values similar to those of the C Group, for the two analysis periods. There was no difference in CSA in the 20-day Group between the ES Groups and the D Group (p> 0.05). After 30 days, all the experimental groups reached CSA values similar to the C Group. CONCLUSIONS: The ES was inefficient for minimizing the muscle fiber atrophy. However, the CT was responsive to ES, and daily applications were more beneficial for the muscle than were alternate-day applications, thus suggesting that the interval for applying ES to denervated muscle is an important variable for CT adaptation.

Distribuição da força plantar e oscilação do centro de pressão em relação ao peso e posicionamento do material escolar / Plantar force distribution and pressure center oscillation in relation to the weight and positioning of school supplies and books in student's backpack

OBJETIVO: Investigou-se a influência da carga e posicionamento do material escolar sobre a distribuição da força plantar (DFP) e trajetória do centro de pressão (COP) em estudantes. MÉTODOS: Participaram 30 voluntários (10,7 ± 1,35 anos), ambos os gêneros, sem alteração postural. Dados baropodométricos foram coletados em sistema de baropodometria computadorizada (Matscan Research, Teckscanâ, 5.72): sem carga (controle); com carga (mochila) de 5, 10 e 15 por cento da massa corporal, posicionada nas regiões anterior e posterior do tronco, ombro direito e esquerdo. RESULTADOS: Sem carga, a DFP foi maior no calcâneo esquerdo comparado ao direito (p< 0,05). Com carga de 10 por cento no ombro esquerdo, a DFP foi maior à direita e menor à esquerda, comparado ao controle (p< 0,05). Com 5 por cento na região posterior do tronco, a DFP foi menor no médio-pé direito (mpD) e antepé esquerdo (apE); com 10 por cento, foi menor no mpD e mpE e maior no artelho direito (atD); com 15 por cento, foi menor no mpD e maior no atD (p< 0,05). A força plantar foi maior no atD com carga de 10 e 15 por cento em relação a 5 por cento (p< 0,05). Com carga de 15 por cento nas regiões anterior e posterior do tronco, a trajetória do COP foi maior (p< 0,05) comparada à carga de 5 por cento. A DFP não foi influenciada pelas diferentes cargas e posições da mochila. CONCLUSÕES: Considerando o aumento da trajetória do COP com carga de 15 por cento, recomenda-se que a carga das mochilas escolares não ultrapasse 10 por cento da massa corporal. Sugere-se investigação das adaptações da postura às diferentes cargas e posições da mochila, visando detectar possíveis alterações e propor ações preventivas.

OBJECTIVE: The influence of the weight and positioning of school supplies and books in backpacks, on plantar force distribution (PFD) and pressure center location, was investigated among students. METHODS: Thirty volunteers of both genders participated in the study. Their mean age was 10.76 (± 1.35) years and none of them had postural abnormalities. Baropodometric data were collected using a computerized baropodometric system (Matscan Research, Tekscanâ, 5.72): without load (control) and with loads of 5, 10 and 15 percent of body weight in a backpack, positioned on the back, on the chest and on the right and left shoulders. RESULTS: The PFD without load was greater on the left heel than on the right heel (p< 0.05). With a load of 10 percent on the left shoulder, the PFD was greater on the right and smaller on the left foot, in comparison with the control (p< 0.05). With a load of 5 percent on the back, the PFD was smaller on the right midfoot (RMF) and left forefoot (lff); with 10 percent, it was smaller on the RMF and left midfoot (LMF) and greater on the right toes (RT); with 15 percent, it was smaller on the RMF and greater on the RT (p< 0.05). The plantar force was greater on the RT with loads of 10 percent and 15 percent than it was with loads of 5 percent (p< 0.05). With loads of 15 percent on the back and on the chest, the pressure center displacement was greater than with a load of 5 percent (p< 0.05). The PFD was not influenced by the different loads and backpack positions. CONCLUSIONS: Taking into consideration the increased pressure center displacement with a load of 15 percent, it is recommended that school backpack loads should not exceed 10 percent of body mass. Investigations on posture adaptations to different loads and backpack positions are suggested, in order to detect possible abnormalities and propose preventive actions.

Analise morfometrica dos tecidos muscular e conjuntivo apos desnervacao e estimulacao eletrica de baixa frequencia / Morphometric analysis of muscle and conjunctive tissue after denervation and low-frequency electrial stimulation

A estimulacao eletrica muscular tem sido empregada apos lesao nervosa periferica com o objetivo de minimizar a atrofia e a fraqueza muscular. Experimentos tem demonstrado que ha plasticidade nas fibras musculares, sendo o musculo capaz de sofrer adaptacoes ante fatores como a desnervacao e a estimulacao eletrica. Objetivo: analisar a influencia da estimulacao eletrica sobre o perfil morfometrico do musculo soleo de ratos desnervado por esmagamentodo nervo isquiatico. Metodo: foram utilizados 18 ratos Wistar (196,86g+-33,67) divididos em 3 grupos(n=6): desnervado+estimulacao eletrica (DEE); desnervado(D); e controle(C). Vinte e quatro horas apos o esmagemento do nervo iniciou-se a estimulacao eletrica muscular no grupo DEE(i=5mA, Fase=3ms, f=10Hz) por 30 minutos, durante 20 dias consecutivos. O musculo soleo foi retirado para analise morfometrica. Ressultados: a area medica de seccao transversa das fibras musculares do grupo C foi de 1.035 um2+-210, no grupo D foi de 375 um2+-65 e no grupo DEE, de 600 um2+-126(P<-0,05). A densidade de area do tecido conjuntivo foi significativamente menor (P<-0,05) no grupo DEE (16,61 por cento +- 3,68) em relacao ao D(34,49 por cento +- 4,32), sendo que ambos os grupos apresentaram valores maiores que o grupo C (9,55 por cento +- 2,62). A densidade de area das fibras do musculo soleo foi significativamente maior (P<-0,05) no grupo DEE(83,37 por cento +- 3,68) quando comparada ao grupo D (65,49 por cento +- 4,32). A estimulacao eletrica de baixa frequencia minimizou a atrofia das fibras musculares e a proliferacao de tecido conjuntivo no musculo desnervado

Alongamento da musculatura inspiratoria por intermedio da reeducacao postural global (RPG) / Inspiratory Muscle Stretching through postural global reeduction

O objetivo deste estudo foi analisar o efeito do alongamento dos musculos da cadeia muscular inspiratoria, proposto pelo metodo de reeducacao postural global(RPG), sobre a forca muscular respiratoria e a expansibilidade toracica. Participaram deste estudo 20 voluntarios sadios, do sexo feminino, com idade entre 18 e 23 anos(media=21,2, DP=1,61), que foram divididos de forma randonizada em dois grupos: 10 voluntarios submetidos a postura `ra no chao com bracos fechados` por 20 minutos (grupo RPG) e 10 voluntarios que nao receberam o alongamento, permanecendo em repouso por 20 minutos(grupo controle). Utilizaram-se para a valiacao a medida das pressoes respiratorias maximas e a toracometria em ambos os grupos, antes e apos o periodo estabelecido. Observou-se que o metodo de alongamento utilizado proporcionou aumento da expansibilidade toracica e das pressoes respiratorias maximas, havendo significancia estatistica pelo metodo de Wilcoxon no que se refere a forca dos musculos inspiratorios no grupo que recebeu o alongamento. Tambem houve diferenca significativa na expansibilidade toracica da regiao axilar no grupo RPG quando comparado com o grupo controle. Os resultados sugerem investigar o efeito desse metodo de alongamento em pneumonopatias cronicos, os quais poderiam ser beneficiados, visando a sua utilizacao como recurso fisioterapeutico

Axonal regeneration through muscle autografts submitted to local anaesthetic pretreatment.

Freeze-thawed muscle grafts (FTMG) have been used as an alternative to nerve grafts for the reconstruction of peripheral nerve defects, although their use has some disadvantages. For instance, FTMG may fragment easily after freeze-thawing, a fact impairing their use for surgery. In this study we describe a method to obtain muscle autografts based on the myotoxic properties of local anaesthetics. Fifteen adult rats had their left tibialis anterior muscles injected transcutaneously with 0.3 ml of 2% lidocaine hydrochloride. Twenty-four hours later the injected muscle was removed and a lidocaine muscle graft (LMG) was obtained by trimming the muscle to a rectangular block of approximately 1.0 cm in length. The left sciatic nerve was exposed in the mid-thigh region and a segment removed so that a final 1.0 cm-long gap was produced. The LMG was coaxially autografted to the epineurium between the proximal and distal nerve stumps. In another 15 rats, the sciatic nerve gap was repaired with FTMG obtained from the tibialis anterior muscle. Surgical procedures were similar in both groups. Axonal regeneration and muscle reinnervation were studied quantitatively and ultrastructurally 60 days after the insertion of LMG and FTMG. The results showed that axonal regeneration with the LMG was qualitatively similar to that observed with the FTMG, with no significant differences between groups. We conclude that LMG was a successful muscle graft and a suitable alternative to other denaturing methods, without the disadvantages of FTMG.