Relationship between muscle strength and motor function in Duchenne muscular dystrophy

Measuring muscle strength and motor function is part of Duchenne muscular dystrophy (DMD) assessment. However, the relationship between these variables is controversial. Objective: To investigate the relationship between muscle strength and motor function and between these variables and age. Method: Muscle strength was measured by Medical Research Council (MRC) scale and motor function, by Motor Function Measure (MFM), in 40 non-ambulatory patients. Spearman tests investigated the relationships between muscle strength, motor function and age. Results: Total MRC and MFM scores were strongly related to each other (r = 0.94p 0.05). Strong and moderate relationships between partial muscle strength and motor function scores were found. Higher correlation coefficients were found between total scores and Dimensions 2 (axial/ proximal control) and 3 (distal control) of MFM. Conclusion: Muscle strength and motor function are strongly correlated and seem to decrease proportionally in DMD.Univ Sao Paulo, Fac Med, Dept Fisioterapia Fonoaudiol & Terapia Ocupac, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Fac Med, Dept Neurol, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Fac Med, Dept Neurol, Sao Paulo, SP, BrazilWeb of Scienc

Elaboração e confiabilidade da escala funcional do subir e do descer escada para Distrofia Muscular de Duchenne Elaboration and reliability of functional evaluation on going up and downstairs scale for Duchenne Muscular Dystrophy

CONTEXTUALIZAÇÃO: Os instrumentos de avaliação funcional utilizados para pacientes com distrofia muscular de Duchenne (DMD), citados na literatura, são limitados e escassos, dificultando a tomada de decisão clínica fisioterapêutica. OBJETIVOS: Descrever o processo de criação de uma escala de avaliação funcional do subir e do descer escadas, específica para crianças com diagnóstico de DMD, e examinar sua confiabilidade inter e intraexaminadores. MÉTODOS: A construção da escala seguiu cinco etapas, a saber, elaboração de um roteiro para observação dirigida com base na literatura; observação do subir e do descer em 120 registros filmados de 30 crianças com DMD (5 a 11 anos); elaboração da escala, considerando o grau crescente de dificuldade de execução dos movimentos; criação do manual de preenchimento e submissão da escala e do manual a 10 examinadores, seguida de reajustes para criação da versão final. A confiabilidade foi testada pelo pesquisador (repetibilidade) e dois examinadores independentes (reprodutibilidade). Utilizou-se o Índice de Correlação Intra-Classe (ICC) e a Correlação de Kappa Ponderado. RESULTADOS: A escala elaborada abrange cinco fases para o subir e quatro fases para o descer escadas. Encontrou-se excelente confiabilidade intra/interexaminadores, com valores da Correlação de Kappa Ponderado > 0,78 em todas as fases e ICCs > 0,89, com p<0,05 entre todos os escores. CONCLUSÃO: A escala proposta mostrou excelente repetibilidade e reprodutibilidade, sendo necessária a continuidade do estudo com os objetivos de avaliar sua acurácia e validade e de construir uma ferramenta digital para otimizar a coleta de dados.<br>BACKGROUND: Instruments of functional evaluation for patients with Duchenne Muscular Dystrophy (DMD), available from the literature, are limited and scarce, making clinical decision on Physiotherapy difficulty. OBJECTIVES: To describe the process of creating a functional assessment scale in patients with DMD while going up and down the stairs, as well as to analyse the intra and inter-rater reliability of this scale. METHODS: The scale development consisted of five stages: 1) to elaborate a script for directed observation based upon literature, 2) to describe a sequence of movements assessing 120 video recordings from 30 children (from 5 to 11 years) with DMD while going up and down stairs, 3) to elaborate a scale considering the degree of difficulty to execute the movements, 4) to create handbook, and 5) to submit both the scale and the handbook to be assess by 10 examiners, and review to create the final version. Both repeatability (researcher) and reproducibility (two independent examiners) were tested by using the IntraClass Correlation Coefficient (ICC) and Weighted Kappa respectively. RESULTS: The scale encloses five phases for going up and four phases for going downstairs. Our results showed both excellent intra and intertester reliability, with values of Weighted Kappa > 0.78 in all phases and ICCs > 0.89, with p<0.05 for all scores. CONCLUSION: The proposed scale showed excellent repeatability and reproducibility, requiring continuing the studies to assess its accuracy, validity and to create digital tools to improve data collection

Relationship between the climbing up and climbing down stairs domain scores on the FES-DMD, the score on the Vignos Scale, age and timed performance of functional activities in boys with Duchenne muscular dystrophy

BACKGROUND: Knowing the potential for and limitations of information generated using different evaluation instruments favors the development of more accurate functional diagnoses and therapeutic decision-making. OBJECTIVE: To investigate the relationship between the number of compensatory movements when climbing up and going down stairs, age, functional classification and time taken to perform a tested activity (TA) of going up and down stairs in boys with Duchenne muscular dystrophy (DMD). METHOD: A bank of movies featuring 30 boys with DMD performing functional activities was evaluated. Compensatory movements were assessed using the climbing up and going down stairs domain of the Functional Evaluation Scale for Duchenne Muscular Dystrophy (FES-DMD); age in years; functional classification using the Vignos Scale (VS), and TA using a timer. Statistical analyses were performed using the Spearman correlation test. RESULTS: There is a moderate relationship between the climbing up stairs domain of the FES-DMD and age (r=0.53, p=0.004) and strong relationships with VS (r=0.72, p=0.001) and TA for this task (r=0.83, p<0.001). There were weak relationships between the going down stairs domain of the FES-DMD-going down stairs with age (r=0.40, p=0.032), VS (r=0.65, p=0.002) and TA for this task (r=0.40, p=0.034). CONCLUSION: These findings indicate that the evaluation of compensatory movements used when climbing up stairs can provide more relevant information about the evolution of the disease, although the activity of going down stairs should be investigated, with the aim of enriching guidance and strengthening accident prevention. Data from the FES-DMD, age, VS and TA can be used in a complementary way to formulate functional diagnoses. Longitudinal studies and with broader age groups may supplement this information