New Device for Intrinsic Hand Muscle Strength Measurement: An Alternative to Strain Gauge Handheld Dynamometer

Abstract

An accurate measurement of intrinsic hand muscle strength (IHMS) is required by clinicians for effective clinical decision-making, diagnosis of certain diseases, and evaluation of the outcome of treatment. In practice, the clinicians use Intrins-o-meter and Rotterdam Intrinsic Hand Myometer for IHMS measurement. These are quite bulky, expensive, and possess poor interobserver reliability (37-52%) and sensitivity. The purpose of this study was to develop an alternative lightweight, accurate, cost-effective force measurement device with a simple electronic circuit and test its suitability for IHMS measurement. The device was constructed with ketjenblack/deproteinized natural rubber sensor, 1-MΩ potential divider, and Arduino Uno through the custom-written software. Then, the device was calibrated and tested for accuracy and repeatability within the force range of finger muscles (100 N). The 95% limit of agreement in accuracy from -1.95 N to 2.06 N for 10 to 100 N applied load and repeatability coefficient of ±1.91 N or 6.2% was achieved. Furthermore, the expenditure for the device construction was around US$ 53. For a practical demonstration, the device was tested among 16 participants for isometric strength measurement of the ulnar abductor and dorsal interossei. The results revealed that the performance of the device was suitable for IHMS measurement.

A novel adaptable isometric strength analysis and exercise development system design

“…Measuring of muscle strength and power may be needed while seeking answers to processes such as talent selection, observing training effects, making new training plans, and determining physical fitness in sports. 22,23,30 Strength measurements in the field of medicine may be required in cases such as the diagnosis of diseases and injuries related to the neuro-muscular system, determination of treatment methods, and control of rehabilitation processes. [31][32][33][34]39,51 During the treatment and (or) posttreatment rehabilitation [40][41][42] of injured athletes 28 or sedentary individuals with orthopedic [35][36][37][38] and neurological [31][32][33][34] disorders, due to the limitation of movement caused by the functional disorders in the joints, benefits to the skeletal muscular system can be provided by isometric exercises and measurements.…”

“…26 From this point of view, observing the strength and power changes of athletes may play an important role in the training of elite athletes, in the regulation of competition preparations and training programs, [21][22][23]26,27 stages of return to sport during 28 and after the injury period. 16,29 In addition to strength and power measurement studies in the field of sports, 22,23,30 patients with neurological/neuromuscular [31][32][33][34] and orthopedic disorders, [35][36][37][38] physical therapy and rehabilitation patients, [39][40][41][42] the elderly, 8,43,44 children, [45][46][47] and various special groups [48][49][50] may also need to be observed the changes in strength and power. Strength and power measurements are used in all these groups, for development purposes, control purposes, 35,36,51 diagnosing diseases, 17,30,52 or planning treatments or creating normative data 17,20,47 by receiving feedback, etc.…”

“…A better understanding of the mechanisms underlying the development of strength and power, as well as the development of techniques to increase strength and power, is associated with accurate and reliable measurement of strength and power. 1 Measuring muscle strength and power is important for evaluating the development of athletes' performance in the field of sports, 22,23,30 evaluating various patients, diseases, and treatment processes in the field of medicine. [31][32][33][34] Especially applications on static muscle strength measurement in the field of sports and medicine are frequently encountered.…”

“…In addition to strength and power measurement studies in the field of sports, 22,23,30 patients with neurological/neuromuscular 31–34 and orthopedic disorders, 35–38 physical therapy and rehabilitation patients, 39–42 the elderly, 8,43,44 children, 45–47 and various special groups 48–50 may also need to be observed the changes in strength and power. Strength and power measurements are used in all these groups, for development purposes, control purposes, 35,36,51 diagnosing diseases, 17,30,52 or planning treatments or creating normative data 17,20,47 by receiving feedback, etc.…”

Piezoresistive Elastomer-Based Composite Strain Sensors and Their Applications

“…91 In another study, it was shown how a natural rubber sensor-based dynamometer was used for muscle strength clinical testing and it was an improved, reliable, lightweight and low-cost alternative to the conventional strain gauge systems. 136 Kim et al, produced a PDMS/CNTs strain sensor by combining it with other flexible circuits, they created a complex biomedical sensing system for stretchable applications. Additionally, they investigated the biocompatibility of the PDMS/CNTs composite and no cytotoxicity was reported, the cell viability was high and in vivo experiments proved the appropriateness of the composite for epidermal use.…”