A portable articulated dynamometer for ankle dorsiflexion and plantar flexion strength measurement: a design, validation, and user experience study

Abstract

Monitoring ankle strength is crucial for assessing daily activities, functional ability, and preventing lower extremity injuries. However, the current methods for measuring ankle strength are often unreliable or not easily portable to be used in clinical settings. Therefore, this study proposes a portable dynamometer with high reliability capable of measuring ankle dorsiflexion and plantar flexion. The proposed portable dynamometer comprised plates made of aluminum alloy 6061 and a miniature tension–compression load cell. A total of 41 healthy adult participants applied maximal isometric dorsiflexor and plantar flexor forces on a Lafayette Handheld Dynamometer (HHD) and the portable dynamometer. The results were cross-validated, using change in mean, and two independent examiners evaluated the inter-rater and test–retest reliabilities in separate sessions using intraclass correlation coefficients, standard error of measurement, and minimal detectable change. Both dorsiflexion and plantar flexion measurements demonstrated a strong correlation with the HHD (r = 0.827; r = 0.973) and showed high inter-rater and test–retest reliabilities. Additionally, the participant responses to the user experience questionnaire survey indicated vastly superior positive experiences with the portable dynamometer. The study findings suggest that the designed portable dynamometer can provide accurate and reliable measurements of ankle strengths, making it a potential alternative to current methods in clinical settings.

A Comparison of Different Strength Measurement in Taekwondo: Herman Trainer, Manual Tester, and Standing Long Jump

“…The Lafayette hand-held dynamometer is a proven tool for quantifying muscle strength, measuring various force-related metrics including peak force, time to reach peak force, total test time, average force, real-time force, end force, average force from peak to end, and percentage decrease from peak to end force [38,39]. Its versatility and reliability make it a popular choice for force measurement in athletes [40,41]. It has been stated that hand dynameters, such as the Lafayette manual muscle testing device, have become useful in athletic field tests because they are a convenient, portable, non-invasive, relatively fast, easy, and inexpensive way to objectively measure applied forces [38].…”

Design and validation of a wearable dynamometry system for knee extension-flexion torque measurement

“…Myong et al 20 and Brookshaw et al 21 proposed devices that utilize load cells attached to the limb, allowing the measurement of knee extension, elbow extension, and elbow flexion strength without the need to install equipment in the surrounding environment. Cho et al 22 proposed a device that used load cells to measure the dorsiflexion and plantar flexion of the ankle. These devices demonstrated portability, validity, and reliability comparable to those of IKD.…”