[PA-1-19] The feasibility of fine motor evaluation by rehabilitation ring for individuals with stroke
IntroductionMany individuals with better recovery from stroke still have trouble eating, and zipping a zipper because of their poor fine motor performance. Difficulties in fine motor performance in this population generally result from mild abnormal muscle tone, incoordination, and muscle weakness. The current clinical measures of hand function, such as the Modified Ashworth Scale (MAS), Fugle-Meyer assessment for upper extremity (FMA-UE), or Purdue Pegboard test (PP), are standardized objective tools. However, these measures have some limitationsin this population. It is necessary for an instrument to assess effectively the required components of fine motor performance. This study developed an instrument, the rehabilitation ring. It is designed as a C-shaped structure that can be held in one hand with a cylindrical-type power grasp. The central axis of the ring body comprises a torsion spring so that the ring body can be controlled by grasping and releasing. A force sensor embedded in the ring body can detect movements and the control of finger force, and data on device control can be transmitted to a computer.
PurposeThis study aimed to investigate the relationships of force applied to the rehabilitation ring to muscle tone, pinch strength, and hand dexterity.
Method Participants Ten individuals with stroke were recruited. Experimental procedure First, participants’ grasp strength, pinch strength, and hand dexterity were measured with a Jamar dynamometer, pinch gauge, and the PP, respectively. Then the participants grasped and released (one trial) the rehabilitation ring at a regular pace (1–2 sec/trial). A total of 10 trials were performed with the hemiplegic hand and the healthy hand in turn. Outcome measure Three phases (grasp phase, compression phase, and relaxation phase) were defined according to the measured torque force (gmf) in the time series. The integrated difference (ID) was calculated. A sigmoid function (f(x)=1/(1+exp(x)) was used to perform curve fitting on the measured values. ID was defined as: ID=1/N sumation i=itoN square(yi- ŷi), where yi represents the ith measurement value in the phase and ŷi represents the ith value in the fitted function corresponding to yi. Data analysis A Mann–Whitney U test was used to compare the two groups to investigate the effect of muscle tone (G1: MAS = 0 vs. G2: MAS≧1). Pearson’s correlation was used to explore the relationships among the scores of ID, grasp strength, pinch strength, and hand dexterity.
Results indicated that on the hemiplegic side, pinch strength scores (r = 0.66, p=0.04) and hand dexterity scores (r = 0.69, p = 0.03) were highly positively correlated with the ID of the relaxation phase. However, all analyses of the effect of muscle tone showed nonsignificant differences (p > 0.05).
Discussion The current study supports the detection of the fine motor performance of applied force with the rehabilitation ring for assessing pinch strength and hand dexterity.
PurposeThis study aimed to investigate the relationships of force applied to the rehabilitation ring to muscle tone, pinch strength, and hand dexterity.
Method Participants Ten individuals with stroke were recruited. Experimental procedure First, participants’ grasp strength, pinch strength, and hand dexterity were measured with a Jamar dynamometer, pinch gauge, and the PP, respectively. Then the participants grasped and released (one trial) the rehabilitation ring at a regular pace (1–2 sec/trial). A total of 10 trials were performed with the hemiplegic hand and the healthy hand in turn. Outcome measure Three phases (grasp phase, compression phase, and relaxation phase) were defined according to the measured torque force (gmf) in the time series. The integrated difference (ID) was calculated. A sigmoid function (f(x)=1/(1+exp(x)) was used to perform curve fitting on the measured values. ID was defined as: ID=1/N sumation i=itoN square(yi- ŷi), where yi represents the ith measurement value in the phase and ŷi represents the ith value in the fitted function corresponding to yi. Data analysis A Mann–Whitney U test was used to compare the two groups to investigate the effect of muscle tone (G1: MAS = 0 vs. G2: MAS≧1). Pearson’s correlation was used to explore the relationships among the scores of ID, grasp strength, pinch strength, and hand dexterity.
Results indicated that on the hemiplegic side, pinch strength scores (r = 0.66, p=0.04) and hand dexterity scores (r = 0.69, p = 0.03) were highly positively correlated with the ID of the relaxation phase. However, all analyses of the effect of muscle tone showed nonsignificant differences (p > 0.05).
Discussion The current study supports the detection of the fine motor performance of applied force with the rehabilitation ring for assessing pinch strength and hand dexterity.