Fisioter Mov. 2012 jul/set;25(3):517-24 Lima KCA, Francisco MM, de Freitas PB. 518 seus resultados devem ser utilizados com cautela, pois essa variável não contempla todos os aspectos que envolvem a coordenação e o controle das forças atuantes durante a manipulação de objetos. Os testes 9-PnB e TFMJT indicam características diferentes relacionadas às capacidades manipulativas. [P] Palavras-chave: Função manual. Destreza. Dinamômetro de força muscular. [K]

Diabetic peripheral neuropathy (DPN) affects the sensory function of the hands and, consequently, may negatively impact hand dexterity, maximum grip strength (GS), and hand grip force (GF) control during object manipulation. The aims of this study were to examine and compare the GF control during a simple holding task as well as GS and hand dexterity of individuals with DPN and healthy controls. Ten type 2 diabetic individuals diagnosed with DPN and ten age- and gender-matched healthy controls performed two traditional timed hand dexterity tests (i.e., nine-hole peg test and Jebsen-Taylor hand function test), a GS test, and a GF control test (i.e., hold a instrumented handle). The results indicated that individuals with DPN and controls produced similar GS. However, individuals with DPN took longer to perform the hand dexterity tests and set lower safety margin (exerted lower GF) than controls when holding the handle. The findings showed that mild to moderate DPN did not significantly affect maximum hand force generation, but does impair hand dexterity and hand GF control, which could impair the performance of daily living manipulation tasks and put them in risk of easily dropping handheld objects.

BackgroundThe relationship between normal and tangential force components (grip force – GF and load force – LF, respectively) acting on the digits-object interface during object manipulation reveals neural mechanisms involved in movement control. Here, we examined whether the feedback type provided to the participants during exertion of LF would influence GF-LF coordination and task performance.MethodsSixteen young (24.7 ±3.8 years-old) volunteers isometrically exerted continuously sinusoidal FZ (vertical component of LF) by pulling a fixed instrumented handle up and relaxing under two feedback conditions: targeting and tracking. In targeting condition, FZ exertion range was determined by horizontal lines representing the upper (10 N) and lower (1 N) targets, with frequency (0.77 or 1.53 Hz) dictated by a metronome. In tracking condition, a sinusoidal template set at similar frequencies and range was presented and should be superposed by the participants’ exerted FZ. Task performance was assessed by absolute errors at peaks (AEPeak) and valleys (AEValley) and GF-LF coordination by GF-LF ratios, maximum cross-correlation coefficients (rmax), and time lags.ResultsThe results revealed no effect of feedback and no feedback by frequency interaction on any variable. AEPeak and GF-LF ratio were higher and rmax lower at 1.53 Hz than at 0.77 Hz.ConclusionThese findings indicate that the type of feedback does not influence task performance and GF-LF coordination. Therefore, we recommend the use of tracking tasks when assessing GF-LF coordination during isometric LF exertion in externally fixed instrumented handles because they are easier to understand and provide additional indices (e.g., RMSE) of voluntary force control.

RESUMO | O sucesso na realização de atividades manipulativas é crucial para um estilo independente. Como os diabéticos podem apresentar alterações sensoriais nas mãos, podem demonstrar alterações funcionais em tarefas manipulativas. Assim, o objetivo deste estudo foi comparar o desempenho de indivíduos diabéticos não neuropatas com o de não diabéticos em tarefas manipulativas e na capacidade de geração de força de preensão palmar máxima. Treze diabéticos sem diagnóstico de neuropatia (48, 6±11,51 anos; 79,9±10,88 kg; 1, 68 ±0, 09 m) e 13 controles pareados por sexo e idade (48,5±10, 09 anos; 76, 44±11, 79 kg; 1, 69±0, 1 m) participaram do estudo. A sensibilidade das mãos foi avaliada por meio do kit de monofilamentos Semmes-Weinstein e, em seguida, foram aplicados três testes comumente utilizados para avaliação da função manual na seguinte ordem: teste de função manual Jebsen Taylor (TFMJT), teste dos nove pinos nos buracos (9-PnB) e teste de força de preensão palmar máxi-ma (FPmax). Os resultados do teste de sensibilidade cutânea indicaram que oito diabéticos apresentaram sensibilidade cutânea normal e cinco, alguma alteração sensorial detectá-vel pelo monofilamento, a qual, no entanto, não os caracterizavam como neuropatas. Com relação aos testes funcionais, os resultados não indicaram qualquer diferença entre os grupos para os desempenhos nos três testes realizados (diabéticos e controles -TFMJT: 26, 15±3, 06 e 25, 78±1,29 s; 9-PnB: 15,33±1,35 e 15, 48±2,39 s; FPmax: 41, 15±10,59 e 43, 69±12,59 kgf). Assim, podemos concluir que indivíduos diabéticos sem neuropatia diabética periférica não apresentam qualquer alteração funcional nos membros superiores e na capacidade de gerar força de preensão palmar máxima.Descritores | mão; avaliação; destreza motora; diabetes mellitus.ABSTRACT | A successful object manipulation is crucial for living an independent life. As diabetic individuals could present sensory deficits in their hands, they could decrease functional performance in tasks involving object manipulation. The aim of the study was to compare the performance of diabetic individual without diagnosis of neuropathy with non-diabetic healthy individuals in manipulation task and their maximum power grip strength. Thirteen diabetic individuals without peripheral neuropathy diagnosis (48.6±11.51 years-old; 79.9±10.88 kg; 1.68±0.09 m) and 13 healthy age-and gender-matched controls (48.5±10.09 years-old; 76.44±11.79 kg; 1.69±0.1 m) participated in the study. Hand cutaneous sensitivity was assessed by the Semmes-Weinstein monofilaments examination (SWME) followed by the application of three tests commonly used to assess hand function: JebsenTaylor hand function test (JTHFT), nine hole peg test (9HPT) and maximum power grip strength test (GSmax). The results of SWME revealed that eight diabetic individuals presented normal cutaneous sensitivity and five showed mild sensory losses, but that was not enough to characterize them as neuropathic diabetics. Regarding the hand function tests, the results revealed no difference b...

The main aim of this study was to examine the relationship between GS Max and the performance in a hand dexterity task. Twenty-four healthy adults (12 males) between 20 and 39 years of age performed the nine hole peg test (9-HPT) and the maximum grip strength test (Jamar ® hydraulic hand dynamometer). The results revealed that males were stronger than females and dominant hand was stronger than non-dominant hand. Moreover, males and females had similar performance in the 9-HPT, but both groups had better performance when using their dominant hand compared to their non-dominant one. Finally, and most importantly, the results revealed that there was no significant relationship between GS Max and individuals’ performance in the 9-HPT. The lack of relationship between them indicates that digits dexterity assessed by 9-HPT is not dependent on maximum grip strength exerted by the hand, suggesting that the evaluation of hand function should not be only based upon the results of the maximum grip strength test. Consequently, other grip strength related measures (e.g., rate of grip force development, grip force control) should be taken into consideration for hand function assessment.