Análise biomecânica dos efeitos da crioterapia no tratamento da lesão muscular aguda

Abstract

A crioterapia é amplamente utilizada por atletas profissionais e amadores no tratamento agudo de lesões musculares. Este trabalho teve como objetivo analisar as propriedades mecânicas do músculo gastrocnêmio lesionado por impacto direto e tratado com crioterapia. Para tanto, foram utilizadas 24 ratas Wistar, divididas em três grupos experimentais: grupo controle (C): animais mantidos em gaiolas-padrão por seis dias; grupo lesionado (L): animais submetidos à lesão por mecanismo de impacto no gastrocnêmio, sem tratamento e mantidos em gaiolas-padrão por seis dias; grupo lesionado e tratado com crioterapia (LC): animais submetidos à lesão, tratados com uma sessão de crioterapia, imediatamente após a lesão e mantidos em gaiolas-padrão por seis dias. Após essas etapas, os animais foram submetidos à eutanásia para que fossem realizados os ensaios mecânicos de tração dos músculos gastrocnêmios direitos, na máquina universal de ensaios (EMIC ® ). A partir dos gráficos carga versus alongamento de cada ensaio, foram calculadas as seguintes propriedades mecânicas: carga no limite máximo (CLM), alongamento no limite máximo (ALM) e rigidez (R). No ALM, o grupo C apresentou diferença estatística (p < 0,05) somente quando comparado com o L. Quando analisadas carga máxima e rigidez, houve diferença estatística (p < 0,05) nos três grupos. Assim, enquanto os músculos lesionados sem tratamento apresentaram diminuição de todas as propriedades mecânicas analisadas, os tratados com crioterapia mostraram melhora das propriedades, porém, sem alcançar o grupo controle. Dessa forma, podemos concluir que a sessão de crioterapia por imersão imediata após a lesão promoveu melhora das propriedades mecânicas analisadas.Palavras-chave: lesões de tecidos moles, músculo esquelético, crioterapia, ratos. ABSTRACTCryotherapy is widespread used in the acute treatment of muscle injuries of professional and unprofessional athletes. The purpose of this study was the investigation of mechanical properties of gastrocnemius muscle submitted to a impact mechanism of injury and treated with cryoterapy. Therefore, twenty four female Wistar rats were divided into three groups: Control (C): animals housed in standard cages for six days; Lesion (L): animals submitted to a direct impact mechanism of injury in the gastrocnemius muscle, without any treatment and kept into standard cages during six days; Lesion e cryotherapy (LC): animals submitted to the contusion, treated with a single session of cryotherapy immediately after lesion and housed in standard cages during six days. After those protocols, the rats were killed and their right gastrocnemius muscle were dissected and submitted to a mechanical test of traction in a universal assays machine (EMIC ® ). From the load versus elongation curves, the following mechanical properties were obtained: Maximum limit load (MLL), maximum limit elongation (MLE) and stiffness (St). There was a statistically difference between all groups in MLL and St. However, in the MLE there was statistically difference only between gro...

Propriedades mecânicas do músculo de ratos adultos e idosos, exercitado pós-imobilização

“…These two structures are considered responsible for the viscoelastic resistance of the musculotendinous complex. 17 …”

“…The animals were euthanized using an overdose of ketamine hydrochloride and xylazine hydrochloride applied intraperitoneally, 17,19 following the principles of ethics in animal research. The right gastrocnemius of each animal was excised by means of the removal of the skin and of some soft parts, taking the precaution to maintain its integrity, preserving the origin in the distal third of the femur and the calcaneal insertion to facilitate the fixation of the piece to the testing machine.…”

“…After the fixation of the muscle to the testing machine, the muscle was submitted to axial traction with a preload of 300g 17 for 30 seconds, with the intention of promoting the system's accommodation.…”

“…13-17 Thus, the evaluation of the mechanical properties of the muscle tissue is an important procedure, consisting of a very useful tool for the establishment of clinical/surgical protocols and rehabilitation programs, as it provides relevant knowledge about the possible muscle adaptations and alterations in the presence of external stimuli. 17 It is also difficult to find studies that address these processes in the aged skeletal muscle.…”

Supplement with Cystoseira canariensis promotes an increase of resistance to the maximum load in the grastrocnemius muscle of female rats

“…For each load increase applied to the muscle, there was a resulting stretching value, which enabled the construction of graphics showing load versus stretching, by using the software Microsoft Excel Xp Professional ® . Afterwards, the following mechanical properties were analyzed: load at maximum limit; stretching at maximum limit; and rigidity [21][22][23][24] .…”