Validade e confiabilidade do teste do esfigmomanômetro modificado para a avaliação da força muscular de membros inferiores e tronco de indivíduos na fase crônica do acidente vascular encefálico

Abstract

Muscular weakness is often observed in subjects with stroke. The methods commonly used to assess this outcome in clinical settings have significant disadvantages. The objectives of this study were: a) to investigate the concurrent criterion-related validity and the test-retest and inter-rater reliabilities of the MST for the assessment of LL and trunk muscular strength of subjects with chronic stroke; and b) to verify whether the use of different outcome measures affected the measures and their properties. The strength of the hip flexors/extensors/abductors, knee flexors/extensors, ankle dorsiflexors/plantar flexors, trunk flexors/lateral flexors/extensors/rotators of 59 subjects with chronic stroke (57.80±13.79 y;90.97±71.34 months since the onset of stroke) was assessed with a hand-held dynamometer (HHD) and the MST bilaterally on the first day of assessment by Examiner 1. On the second day (one to four weeks apart), Examiners 1 and 2 assessed the strength of these muscular groups with the MST independently, following the same protocol. An assistant examiner read and recorded all of the measures. One-way ANOVA was used to compare the strength values obtained with the MST. To investigate the validity, the Pearson correlation test was used to assess the correlation between the measures of the HHD (Kgf) and the MST (mmHg). Simple regression analyses were used to identify the best model that could explain the relationships between the measures obtained with both devices and provide the estimated equations to predict the force values in Kgf, based on the values, in mmHg. Intraclass correlation coefficient (ICC) was used to investigate test-retest and inter-rater reliabilities (=0.05). ANOVA showed similar values among the outcome measures for all muscular groups (0.003F0.08;0.92p1.00). Significant values classified as moderate to very high were found for validity (0.79r0.90;p0.001), test-retest reliability (0.57CCI0.98;p0.001), and inter-rater reliability (0.53CCI0.97;p0.001) for all muscular groups considering the different outcome measures, except the inter-rater reliability of the first trial of the plantar flexors of the nonparetic side, for which reliability was very low (CCI=0.34;p0.001). Linear regression analyses demonstrated that the values in mmHg were good predictors of the values in Kgf (0.62r20.90;p0.001). Therefore, the MST showed adequate concurrent criterion-related validity and test-retest and inter-rater reliabilities for the assessment of LL and trunk muscular strength of subjects with chronic stroke, with only one measure required, after familiarization. The mean of two MST trials are recommended for the plantar flexors of the nonparetic side, when assessed by two examiners. Estimated regression equations for the prediction of the values in kgf from the values in mmHg were provided.