Advance in Mechanism of Hip Muscle Training for Knee Osteoarthritis (review) / 中国康复理论与实践

Knee osteoarthritis (KOA) is a common chronic degenerative joint disease. Hip muscle training, with the advantage of convenience and non-invasion, has been attached great importance by people gradually. Hip muscle training may affect keen medial compartment load, the strength and the electromyography signal of the muscle around the knee joint, and strong hip abductor can protect cartilage, which leads to change the load of the knee joint, and alleviate clinical symptoms. This article reviewed the mechanism of hip muscle training for knee osteoarthritis from the views of biomechanical simulation and electromyography.

Comparison of two incremental protocols for evaluation of hip extension / Comparação de dois protocolos progressivos na avaliação da extensão de quadril

Abstract Introduction: The hip muscles play an important role in controlling the transverse and frontal plane of the femur during displacement. The hip extension and abduction/adduction exercises are among the most widely evaluated protocols both clinically and in research. Objective: To compare which assessment protocol in an isokinetic strength regime (distal grip-ankle vs. proximal grip-knee) best represents the action of hip extension and to analyze the test-retest reliability in the variables peak force (PF) and work (W). Methods: A total of 20 subjects participated in this research. All participants were female. The mean and standard deviations of age, weight and height were 21 ± 3.9 years, 65 ± 11 kg, 166 ± 3.4 cm, respectively. Results: Significant differences were found in both variables (PF and W) between protocols 1 and 2 (p < 0.05) on assessment days 1 and 2. No differences between days 1 and day 2 in either protocol (p < 0.05) were found. Index values of interclass correlation (ICC) of protocol 1 ranged between 0.38 and 0.86. In protocol 2 the ICC range was between 0.33 and 0.87. Conclusions: In light of these results, the hip extension exercise with a proximal grip best represents the strength of the muscle groups involved in this action.

Resumo Introdução: Os músculos do quadril desempenham um papel importante no controle do plano transverso e frontal do fêmur durante o deslocamento. Os exercícios de extensão e abdução/adução do quadril estão entre os protocolos mais amplamente avaliados tanto na clínica como na pesquisa. Objetivo: Comparar qual protocolo de avaliação em um regime de força isocinética (aperto distal no tornozelo versus aperto proximal no joelho) melhor representa a ação de extensão de quadril e analisar a confiabilidade teste-reteste nas variáveis de força máxima de (FM) e trabalho (T). Métodos: Um total de 20 indivíduos participou desta pesquisa. Todos os participantes eram do sexo feminino. A média e desvios-padrão de idade, peso e altura foram 21 ± 3.9 anos, 65± 11 kg e 166 ± 3.4 cm, respectivamente. Resultados: Foram encontradas diferenças significativas em ambas as variáveis (FM e T) entre protocolos 1 e 2 (p < 0,05) nos dias 1 e 2 de avaliação. Não houve diferenças entre os dias 1 e dia 2 em qualquer protocolo (p < 0,05). O índice de valores de correlação interclasse (ICC) do protocolo 1 variou entre 0,38 e 0.86. No protocolo 2 a faixa do ICC foi entre 0,33 e 0,87. Conclusões: Tendo em conta estes resultados, o exercício de extensão de quadril com uma fixação proximal é quem melhor representa a força dos grupos musculares envolvidos nesta ação.

Effect of Strengthening Training of Hip Muscles on Functional Ankle Instability / 中国康复理论与实践

Objective To observe the effect of strengthening training of hip muscles on functional ankle instability (FAI). Methods From May, 2015 to June, 2016, 40 patients with FAI were randomly divided into control group (n=20) and observation group (n=20). Both groups were treated with routine exercise training including muscle strength and proprioceptive training of the ankle joint, while the treat-ment group received hip muscle strength training in addition, for six weeks. They were evaluated with hip force assessment, postural stabili-ty assessment, Star Excursion Balance Test (SEBT) and Cumberland Ankle Instability Tool (CAIT). Results There was no significant differ-ence in all the indexes between two groups before treatment (P>0.05). After treatment, the peak torques of hip muscles increased in the ob-servation group (t>3.528, P<0.01);the overall stability index, anteroposterior stability index, middle-lateral stability index decreased in both groups (t>2.360, P<0.05);the distance of eight direction in SEBT increased in both groups (t>2.254, P<0.05);the score of CAIT increased in both groups (t>3.268, P<0.01). All the above indexes were better in the observation group than in the control group (t>2.161, P<0.05). Conclusion Strengthening training of hip muscle, based on conventional ankle muscle strength and proprioceptive training, could facilitate to improve FAI.

Effect of Strengthening Training of Hip Muscles on Functional Ankle Instability / 中国康复理论与实践

Objective To observe the effect of strengthening training of hip muscles on functional ankle instability (FAI). Methods From May, 2015 to June, 2016, 40 patients with FAI were randomly divided into control group (n=20) and observation group (n=20). Both groups were treated with routine exercise training including muscle strength and proprioceptive training of the ankle joint, while the treat-ment group received hip muscle strength training in addition, for six weeks. They were evaluated with hip force assessment, postural stabili-ty assessment, Star Excursion Balance Test (SEBT) and Cumberland Ankle Instability Tool (CAIT). Results There was no significant differ-ence in all the indexes between two groups before treatment (P>0.05). After treatment, the peak torques of hip muscles increased in the ob-servation group (t>3.528, P<0.01);the overall stability index, anteroposterior stability index, middle-lateral stability index decreased in both groups (t>2.360, P<0.05);the distance of eight direction in SEBT increased in both groups (t>2.254, P<0.05);the score of CAIT increased in both groups (t>3.268, P<0.01). All the above indexes were better in the observation group than in the control group (t>2.161, P<0.05). Conclusion Strengthening training of hip muscle, based on conventional ankle muscle strength and proprioceptive training, could facilitate to improve FAI.

Electromyographic preactivation pattern of the gluteus medius during weight-bearing functional tasks in women with and without anterior knee pain / Padrão de pré-ativação eletromiográfica do glúteo médio durante atividades funcionais com descarga de peso em mulheres com e sem dor anterior do joelho

BACKGROUND: Proximal factors have been proposed to influence the biomechanics of the patellofemoral joint. A delayed or diminished gluteus medius (GM) activation, before the foot contact on the ground during functional activities could lead to excessive femur adduction and internal rotation and be associated with anterior knee pain (AKP). There are few studies on this topic and the results were inconclusive, therefore, it is necessary to investigate the GM preactivation pattern during functional activities. OBJECTIVE: To compare the GM electromyographic (EMG) preactivation pattern during walking, descending stairs and in single leg jump task in women with and without AKP. METHODS: Nine women clinically diagnosed with AKP and ten control subjects with no history of knee injury participated in this study. We evaluated GM EMG linear envelope before the foot contact on the ground during walking and GM onset time and EMG linear envelope during descending stairs as well as in a single leg vertical jump. Mann-Whitney U tests were used to determine the between-group differences in GM EMG preactivation pattern. RESULTS: No between-group differences were observed in GM linear envelope during walking (P=0.41), GM onset time and linear envelope during descending stairs (P=0.17 and P=0.15) and single leg jump (P=0.81 and P=0.33). CONCLUSIONS: Women with AKP did not demonstrated altered GM preactivation pattern during functional weight bearing activities. Our results did not support the hypothesis that poor GM preactivation pattern could be associated with AKP.

CONTEXTUALIZAÇÃO: Tem sido proposto que fatores proximais influenciam a biomecânica da articulação fêmoro-patelar. Um atraso ou diminuição da ativação do glúteo médio (GM) antes do contato do pé no solo, durante atividades funcionais, poderia levar a adução e rotação interna excessiva do fêmur e provocar a dor anterior do joelho (DAJ). Existem poucos estudos sobre o assunto, e os resultados não foram conclusivos; assim, há necessidade de estudar a pré-ativação do GM durante atividades funcionais. OBJETIVO: Comparar o padrão de pré-ativação eletromiográfica (EMG) do GM durante a caminhada, descida de degraus e salto unipodal entre mulheres com e sem DAJ. MÉTODOS: Nove mulheres com diagnóstico clínico de DAJ e dez mulheres sem história de lesão no joelho participaram do estudo. Avaliou-se a envoltória linear do sinal EMG do GM antes do contato do pé no solo, durante caminhada; o tempo de ativação do GM e a envoltória linear do sinal EMG durante descida de degraus e salto unipodal. Utilizou-se o teste Mann-Whitney para determinar a diferença intergrupos no padrão de pré-ativação EMG do GM. RESULTADOS: Não se encontrou nenhuma diferença intergrupos na envoltória linear do GM durante caminhada (P=0.41), no tempo de ativação e na envoltória linear, durante descida de degraus (P=0.17 e P=0.15) e salto unipodal (P=0.81 e P=0.33). CONCLUSÕES: Mulheres com DAJ não apresentaram alterações significativas no padrão de pré-ativação do GM durante atividades funcionais. Os presentes resultados não sustentam a hipótese de que o pobre padrão de pré-ativação do GM esteja envolvido na DAJ.