• Physical Therapy Korea
• /
• v.29 no.1
• /
• pp.28-36
• /
• 2022

Background: It is known that hand strength and fingertip force are used as an indicator of muscle strength and are also highly related to the various chronic symptoms and even lifespan. To use the individual fingertip force (IFF) as a quantitative index for clinical evaluation, the IFF should be measured and analyzed with various variables from various subjects, such as the normal range of fingertip force and the difference in its distribution by disease. Objects: We tried to measure and analyze the mean maximum IFF distribution during grasping a cylindrical object in healthy adults and patients with spinal cord injury (SCI). Methods: Five Force-sensitive resistor (FSR) sensors were attached to the fingertips of 24 healthy people and 13 patients with SCI. They were asked to grip the object three times for five seconds with their maximum effort. Results: The mean maximum IFF of the healthy adult group's thumb, index, and middle finger was similar statistically and showed relatively larger than IFF of the ring and small finger. It is a 3-point pinch grip pattern. All fingertip forces of patients with SCI decreased by more than 50% to the healthy group, and their IFF of the middle finger was relatively the largest among the five fingertip forces. The cervical level injured SCI patients showed significantly decreased IFFs compared to thoracic level injured SCI patients. Conclusion: We expect that this study results would be helpful for rehabilitation diagnosis and therapy goal decision with robust further study.

• The Journal of Korean Physical Therapy
• /
• v.32 no.4
• /
• pp.198-202
• /
• 2020

Purpose: This study examined the effects of a paraffin treatment with exercise on the muscle strength and fatigue of the hand according to the use of smartphones. Methods: The measurement subjects were 30 healthy males in their 20s who were divided randomly into the control and paraffin treatment groups. A typing exercise using a smartphone was performed. The pinch grip force was measured to evaluate the muscle strength of the thumb, and muscle fatigue analysis using electromyography was performed to analyze muscle fatigue. Results: The functional changes to the arm and the fatigue of the hand through the use of a smartphone were examined to determine the effects of the paraffin treatment. The dominant hand-pinch grip force test did not show a significant difference, but the non-dominant hand-pinch grip force test showed a significant difference between the groups (p=0.030). In the dominant hand fatigue test, there was a significant difference between the groups (p=0.037). In the non-dominant hand, there was a significant difference between time (p=0.012) and the groups (p<0.001). Conclusion: The effects of paraffin intervention on the hand muscle strength and fatigue due to repeated use of the smartphone were confirmed. These results can be used as a basis for clinical use and can be a guide for the correct use of smartphones, which are essential in modern life.

• Journal of the Korean Society of Physical Medicine
• /
• v.13 no.2
• /
• pp.109-114
• /
• 2018

PURPOSE: The purpose of this study conducted the experiment to check change of ability to grip depending on normal male adult's elbow flexion angle and the effect of kinesiology tape application. METHODS: Normal male adults who studies in H university where located in Kyoungbook state and did not have any factors like fracture, osteoarthritis, deformities and non-neurologic issue which might influence the result of this study were selected as subjects. Elbow of subjects were applied by 5cm wideness kinesiology tape and elbow's angle was selected by $0^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$ using Goniometer. The change of ability to grip depending on flexion was measured by an electronic dynamometer before and after taping. RESULTS: Before and after taping elbow joint, both ability to grip decrease in more flexion angle and $135^{\circ}$ of elbow flexion was lowest value, 299.84N. Using kinesiology tape, neutral position $0^{\circ}$ was the highest value, 352.26N. The lowest was 331.68N on $135^{\circ}$. According to verifying the change of ability to grip depending on elbow flexion and the change of ability to grip after taping with paired t-test, the result was p<.05, there was significant difference. CONCLUSION: Using electronic dynamometer and estimating the ability to grip after and before kinesiology tape, the ability to grip decrease in more elbow flexion. The ability to grip after using kinesiology tape was relatively higher than before taping.

• Health Policy and Management
• /
• v.29 no.3
• /
• pp.303-311
• /
• 2019

Background: Cerebrovascular disease is included in four major diseases and is a disease that has high rates of prevalence and mortality around the world. Moreover, it is a disease that requires a high cost for long-term hospitalization and treatment. This study aims to figure out the correlation between grip strength, which was presented as a simple, cost-effective, and relevant predictor of cerebrovascular disease, and cerebrovascular disease based on the results of a prior study. And furthermore, our study compared model suitability of the model to measuring grip strength and relative grip strength as a predictor of cerebrovascular disease to improve the quality of cerebrovascular disease's predictor. Methods: This study conducted an analysis based on the generalized linear mixed model using the data from the Korea Longitudinal Study of Ageing from 2006 to 2016. The research subjects consisted of 9,132 middle old age people aged 45 years or older at baseline with no missing information of education level, gender, marital status, residential region, type of national health insurance, self-related health, smoking status, alcohol use, and economic activity. The grip strength was calculated the average which measured 4 times (both hands twice), and the relative grip force was divided by the body mass index as a variable considering the anthropometric figure that affects the cerebrovascular disease and the grip strength. Cerebrovascular diseases, a dependent variable, were investigated based on experiences diagnosed by doctors. Results: An analysis of the association between grip strength and found that about 0.972 (odds ratio [OR], 0.972; 95% confidence interval [CI], 0.963-0.981) was the incidence of cerebral vascular disease as grip strength increased by one unit increase and the association between relative grip strength and cerebrovascular disease found that about 0.418 (OR, 0.418; 95% CI, 0.342-0.511) was the incidence of cerebral vascular disease as relative grip strength increased by unit. In addition, the model suitability of the model for each grip strength and relative grip strength was 11,193 and 11,156, which means relative grip strength is the better application to the predictor of cerebrovascular diseases, irrespective of other variables. Conclusion: The results of this study need to be carefully examined and validated in applying relative grip strength to improve the quality of predictors of cerebrovascular diseases affecting high mortality and prevalence.

• The Journal of Natural Sciences
• /
• v.13 no.1
• /
• pp.25-33
• /
• 2003

Experiment setup was designed to observe the grip pressure and the center of gravity during golf swing. The experimental results of grip pressure and center of gravity during swing showed the constant type in the envelop of force intensity of a stable KPGA pro as a function of time.

• Proceedings of the Acoustical Society of Korea Conference
• /
• 1994.06a
• /
• pp.644-649
• /
• 1994

Recent studies reveal that grip forces due to repeated mechanical vasocompressions are most significant for the genesis of vibration-induced which finger syndrome (VWF). Therefore, exerted grip force was regarded as a dependent variable in 2 experiments and the effects of noise and vibrations of different weighted acceleration levels were studied. Neither grip forces nor peripheral blood flow as indicated by finger skin temperature were influenced by noise or vibrations. the cause of VWF is therefore presumed to be a concomitant variable which correlates with weighted accelerations and with grip forces as well. A possible factor is the weight of hand-held vibrating tools.

• Transactions on Control, Automation and Systems Engineering
• /
• v.4 no.1
• /
• pp.9-16
• /
• 2002

In this paper, we intend to demonstrate a new intuitive force-feedback device for advanced VR applications. Force feed-back for the device is tension based and is characterized by 7 degrees of freedom (DOF); 3 DOF for translation, 3 DOF for rotation, and 1 DOF for grasp). The SPIDAR-G (Space Interface Device for Artificial Reality with Grip) will allow users to interact with virtual objects naturally by manipulating two hemispherical grips located in the center of the device frame. We will show how to connect the strings between each vertex of grip and each extremity of the frame in order to achieve force feedback. In addition, methodologies will be discussed for calculating translation, orientation and grasp using the length of 8 strings connected to the motors and encoders on the frame. The SPIDAR-G exhibits smooth force feedback, minimized inertia, no backlash, scalability and safety. Such features are attributed to strategic string arrangement and control that results in stable haptic rendering. The design and control of the SPIDAR-G will be described in detail and the Space Graphic User Interface system based on the proposed SPIDAR-G system will be demonstrated. Experimental results validate the feasibility of the proposed device and reveal its application to virtual reality.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.3
• /
• pp.1229-1237
• /
• 2012

This study aimed to investigate the effect of hand grip force on the activity of shoulder muscles in 2 arm postures. The muscle activity of the upper trapezius, lower trapezius, infraspinatus, anterior deltoid, and posterior deltoid muscles in 22 healthy subjects (11 men and 11 women) were measured using surface electrodes during 4 hand gripping tasks (0%, 30%, 50%, and 70% of maximum voluntary contraction) in 2 shoulder positions (neutral position and $90^{\circ}$ elevation position). Among changing grip force significantly differenced infraspinatus, anterior deltoid, and posterior deltoid muscles' activity in the shoulder neutral position(p<0.05). In the shoulder $90^{\circ}$ elevation position, anterior deltoid, posterior deltoid muscles' activity was significantly differenced(p<0.05). Hand gripping was found to alter muscle activation. The hand grip task activated the infraspinatus muscle in the neutral position and inhibited the deltoid muscle in the $90^{\circ}$ elevation position. This finding may prove useful for the development preventative measures and rehabilitation strategies for shoulder injuries.

• Journal of the Korean Society of Safety
• /
• v.12 no.4
• /
• pp.209-213
• /
• 1997

Manual lifting techniques are commonly defined in terms of the postures adopted at the start of the lift. Quantitative definition is problematic, however, because the absolute joint angles adopted to lift an object are influenced by task parameters, such as the initial height of the load. The main objective of this study is to investigate the grip strength of the both hands at the initial lifting points. The survey is conducted by measuring the compression force, anthropometric data and grip strength at the lifting postures for the subjects(n=50) who is assigned to their job as usual. The experiment is peformed at the four lifting postures which involving the combination of two horizontal factors(H1 : 35 cm, H2 : 55 cm) and two vertical factors(V1 : 20~80 cm, V2 : 47~102 cm). The analysis result of lifting posture indicated that each H1-V1, H2-V1 combinations are about 60$^{\circ}$ and each H1-V2, H2-V2 combinations are about $30^{\circ}$. There are significant differences on grip strength between $60^{\circ}$ and $30^{\circ}$ stooped posture. The results of this study can be provided a method defining lifting postures at the minimum grip strength. Also, it is eliminated a hazard of the injuries which are cumulative trauma disorders(CTDs) and back pain, increased a productivity and improved a welfare of workers.

• Preventive Nutrition and Food Science
• /
• v.20 no.2
• /
• pp.133-136
• /
• 2015

Freshwater softshell turtle (Trionyx sinensis) extract has been used traditionally as a tonic soup, and to recover from physical fatigue. To support these claims, the forelimb grip strength of mice was measured after feeding a soft-shell turtle extract for 7 days. The T. sinensis extract significantly increased the grip strength to $1.25{\pm}0.07N$ (P<0.01), which is 16.8% higher than the force on day 0. After exercising, the blood glucose levels in extract-fed mice were 202% higher and urea levels were 73% lower, which were both significantly different than the levels observed after control treatment. Lactate dehydrogenase was significantly higher by 314%, and glutathione peroxidase increased by 165%. In addition, the obesity markers, serum triglyceride and cholesterol, decreased to 62% and 49%, respectively, after mice were fed the extract. These data show that the T. sinensis extract provided more energy for forelimb exercise, prevented protein catabolism and muscle fatigue, and decreased the oxidative stress caused by an exhaustive workout.