Strength deficit of knee flexors is dependent on hip position in adults with chronic hemiparesis

BACKGROUND: The extent to which muscle length affects force production in paretic lower limb muscles after stroke in comparison to controls has not been established. OBJECTIVES: To investigate knee flexor strength deficits dependent on hip joint position in adults with hemiparesis and compare with healthy controls. METHOD: a cross-sectional study with ten subjects with chronic (63±40 months) hemiparesis with mild to moderate lower limb paresis (Fugl-Meyer score 26±3) and 10 neurologically healthy controls. Isometric knee flexion strength with the hip positioned at 90° and 0° of flexion was assessed randomly on the paretic and non-paretic side of hemiparetic subjects and healthy controls. Subjects were asked to perform a maximal isometric contraction sustained for four seconds and measured by a dynamometer. The ratio of knee flexor strength between these two hip positions was calculated: Hip 0°/Hip 90°. Also, locomotor capacity was evaluated by the timed up and go test and by walking velocity over 10 meters. RESULTS: In subjects with hemiparesis, absolute knee flexion torque decreased (p<0.001) with the hip in extension (at 0°). The ratio of knee flexor torque Hip 0°/Hip 90° on the paretic side in hemiparetics was lower than in controls (p=0.02). CONCLUSIONS: Weakness dependent on joint position is more significant in the paretic lower limb of adults with hemiparesis when compared to controls. More attention should be given to lower limb muscle strengthening exercises in individuals with stroke, with emphasis on the strengthening exercises in positions in which the muscle is shortened.

Confiabilidade da versão brasileira do Wolf Motor Function Test em adultos com hemiparesia / Reliability of the brazilian version of the Wolf Motor Function Test in adults with hemiparesis

CONTEXTUALIZAÇÃO: O Wolf Motor Function Test (WMFT) avalia o membro superior (MS) de adultos com hemiparesia combinando medidas de tempo e qualidade de movimento em movimentos isolados e em tarefas funcionais. OBJETIVOS: Traduzir e adaptar para a língua portuguesa o formulário, a escala de habilidade funcional (EHF) e o manual de aplicação do WMFT e avaliar a confiabilidade intra e inter-observadores. MÉTODOS: Participaram 15 indivíduos com média de idade de 57,9±11,1 anos e 68,5±53,5 meses pós acidente vascular encefálico (AVE). O WMFT foi aplicado por um fisioterapeuta utilizando as informações do manual e cotado por dois outros fisioterapeutas independentes pela observação dos vídeos. Foram acrescentadas informações mais detalhadas na EHF sobre a movimentação compensatória em relação à escala original. A confiabilidade intra e interobservadores do desempenho no tempo e da EHF dos itens individuais e do escore total foi avaliada pelo Coeficiente de Correlação Intraclasse (CCI) e pelo método Bland e Altman. Kappa ponderado (Kp) foi utilizado para avaliar a concordância intra e interobservadores da EHF. RESULTADOS: O CCI interobservador do desempenho no tempo foi >0,75 em 13 das 15 tarefas. A EHF apresentou CCI interobservador entre 0,87 e 0,99 em todas as tarefas e Kp entre 0,63 e 0,92. O CCI intraobservador do tempo variou entre 0,99 e 1 e na EHF, entre 0,96 e 1. O Kp intraobservador na EHF nas tarefas variou entre 0,79 e 0,96, sendo 0,93 para o escore total. CONCLUSÃO: A versão brasileira do WMFT demonstrou confiabilidade adequada para avaliar o MS parético pós-AVE.

BACKGROUND: The Wolf Motor Function Test (WMFT) evaluates the upper limb (UL) performance of adults with hemiparesis by combining time and quality of movement measures in both isolated movements and functional tasks. OBJECTIVES: To translate and adapt the WMFT form, functional ability scale (FAS) and manual to Brazilian Portuguese and evaluate the intra and inter-rater reliabilities. METHODS: Fifteen individuals with a mean age of 57.9±11.1 years and a mean time since stroke onset of 68.5±53.5 months participated. The WMFT was administered by one physiotherapist based on information in the manual, and video observations were assessed by two other independent physical therapists. Information regarding compensatory movements was included in the FAS. Intra-class correlation coefficients (ICCs) and Bland-Altman plots were calculated to examine the intra- and inter-rater reliabilities for performance time and FAS, whereas weighted kappa (Kp) was used to examine the agreement strength for FAS. RESULTS: The inter-rater ICC values for performance time were above 0.75 in 13 of the 15 tasks. For the FAS, they ranged from 0.87-0.99 for all evaluated tasks, with Kp values ranging from 0.63-0.92. For intra-rater reliability, the ICC ranged from 0.99-1.0 and from 0.96-1.0 for time measurement and FAS, respectively. Kp values ranged from 0.79-0.96 for individual and 0.93 for total scores. CONCLUSION: The Brazilian version of the WMFT showed adequate intra- and inter-rater reliabilities for evaluating the paretic UL of individuals with stroke.