Quantification and Modeling of Ankle Stiffness During Standing Balance

Nalam, Varun; Adjei, Ermyntrude; Lee, Hyunglae

doi:10.1109/tbme.2020.3023328

Cited by 14 publications

(19 citation statements)

References 34 publications

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“…Ribeiro et al, 2018;Matos et al, 2021;Nalam et al, 2021). Our results also agree with previous studies showing that frontal-plane ankle stiffness increased with increasing weight on the ankle during standing (Matos et al, 2021;Nalam et al, 2021). While the Matos et al (2021) study did not attempt to isolate the effect of axial loading from the effect of muscle activation, Nalam et al (2021) did try to isolate the effect of axial load analytically.…”

Section: Discussionsupporting

confidence: 89%

“…While no studies have quantified frontal-plane ankle stiffness in a seated posture with applied axial loading, a number of studies have looked at the frontal-plane ankle stiffness during weight-bearing in a standing posture. Our measures of ankle stiffness at axial loading equivalent to 50% body weight (0.055 ± 0.004 Nm/rad/N) are within the range of other studies that quantified frontal plane ankle stiffness at 50% BW [.044 – 0.112 Nm/rad/N] (A. Ribeiro et al, 2018; Matos et al, 2021; Nalam et al, 2021). Our results also agree with previous studies showing that frontal-plane ankle stiffness increased with increasing weight on the ankle during standing (Matos et al, 2021; Nalam et al, 2021).…”

Section: Discussionsupporting

confidence: 80%

“…Our measures of ankle stiffness at axial loading equivalent to 50% body weight (0.055 ± 0.004 Nm/rad/N) are within the range of other studies that quantified frontal plane ankle stiffness at 50% BW [.044 – 0.112 Nm/rad/N] (A. Ribeiro et al, 2018; Matos et al, 2021; Nalam et al, 2021). Our results also agree with previous studies showing that frontal-plane ankle stiffness increased with increasing weight on the ankle during standing (Matos et al, 2021; Nalam et al, 2021). While the Matos et al (2021) study did not attempt to isolate the effect of axial loading from the effect of muscle activation, Nalam et al (2021) did try to isolate the effect of axial load analytically.…”

Section: Discussionsupporting

confidence: 80%

See 2 more Smart Citations

Frontal plane ankle stiffness increases with axial load independent of muscle activity

Villamar

Perreault

Ludvig

2021

Preprint

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Ankle sprains are the most common musculoskeletal injury, typically resulting from excessive inversion of the ankle. One way to prevent excessive inversion and maintain ankle stability is to generate a stiffness that is sufficient to resist externally imposed rotations. Frontal-plane ankle stiffness increases as participants place more weight on their ankle, but whether this effect is due to muscle activation or axial loading of the ankle is unknown. Identifying whether and to what extent axial loading affects ankle stiffness is important to understanding what role the passive mechanics of the ankle joint play in maintaining its stability. The objective of this study was to determine the effect of passive axial load on frontal-plane ankle stiffness. We had subjects seated in a chair as an axial load was applied to the ankle ranging from 10% to 50% body weight. Small rotational perturbations were applied to the ankle in the frontal plane to estimate stiffness. We found a significant, linear, 3-fold increase in ankle stiffness with axial load from the range of 0% bodyweight to 50% bodyweight. This increase could not be due to muscle activity as we observed no significant axial-load-dependent change in any of the recorded muscle activations. These results demonstrate that axial loading is a significant contributor to maintaining frontal-plane ankle stability, and that disruptions to the mechanism mediating this sensitivity of stiffness to axial loading may result in pathological cases of ankle instability.

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Section: Discussionsupporting

confidence: 89%

Section: Discussionsupporting

confidence: 80%

Section: Discussionsupporting

confidence: 80%

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Frontal plane ankle stiffness increases with axial load independent of muscle activity

Villamar

Perreault

Ludvig

2021

Preprint

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“…P OSTURAL control that can be characterized by maintaining, achieving, and restoring equilibrium against gravity during stance or locomotion, is considered as one of the most fundamental motor skills in the lifetime [1]. Insufficient postural control, which often results in larger amounts of postural sway, is highly associated with movement disorders like chronic ankle instability [2], low athletic performance W.-Q. Zheng is with Fuzhou Institute for Data Technology, Fouzhou 350200, China (e-mail: superzwq@163.com).…”

Section: Introductionmentioning

confidence: 99%

“…[3], and many neurocognitive diseases, such as Alzheimer's disease, Parkinson's disease [4]. The center of pressure (CoP, global ground reaction force vector) displacement, which accommodates the sway of the body, is commonly used to assess these diseases [2], [3]. As such a disease usually has a long development and rehabilitation process, long-term CoP monitoring is often required, which is also helpful in improving early diagnosis [4].…”

Section: Introductionmentioning

confidence: 99%

A Shoe-Integrated Sensor System for Long- Term Center of Pressure Evaluation

et al. 2021

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In clinical, the center of pressure (CoP) is commonly used for accessing the stability of a person's postural control, which is highly associated with various neurological diseases and movement disorders such as Alzheimer's disease, Parkinson's disease, chronic ankle instability. Such a disease usually has a long development or rehabilitation process which requires long-term CoP monitoring. The current CoP evaluation process does not meet the requirement, as it is often complicated and expensive through either the lab-based equipment or the clinical evaluation procedure. Different wearable sensor-based systems with less cost and restrictions have emerged, but their way of CoP calculation requires deliberate calibration of the positions of their sensors, which are not feasible in daily CoP monitoring. In this study, we developed a longterm CoP monitoring system in a smart-shoe form. First, a thin and flexible smart insole with optimal sensor locations was designed to be compact and energy sufficient for a whole-day usage. Then, a user-friendly app on the smartphone with a cloud-based data managing system was developed for applications in both clinical and home environments. Additionally, a simplified CoP estimation model was created without the need for calibration. Lastly, a machine learning-based human activity recognition method was incorporated to make the CoP detection process more automatic. Through a thorough validation test with the clinical level lab equipment, our system can generate the CoP measurements with high accuracy.

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