Journal article
3D strength surfaces for ankle plantar- and dorsi-flexion in healthy adults: an isometric and isokinetic dynamometry study
Journal of foot and ankle research, Vol.9(1), pp.43-43
11/10/2016
DOI: 10.1186/s13047-016-0174-1
PMCID: PMC5105238
PMID: 27843491
Abstract
Background: The ankle is an important component of the human kinetic chain, and deficits in ankle strength can negatively impact functional tasks such as balance and gait. While peak torque is influenced by joint angle and movement velocity, ankle strength is typically reported for a single angle or movement speed. To better identify deficits and track recovery of ankle strength after injury or surgical intervention, ankle strength across a range of movement velocities and joint angles in healthy adults is needed. Thus, the primary goals of this study were to generate a database of strength values and 3-dimensional strength surface models for plantarflexion (PF) and dorsiflexion (DF) ankle strength in healthy men and women. Secondary goals were to develop a means to estimate ankle strength percentiles as well as examine predictors of maximal ankle strength in healthy adults.
Methods: Using an isokinetic dynamometer, we tested PF and DF peak torques at five joint angles (-10° [DF], 0° [neutral], 10° [PF], 20° [PF] and 30° [PF]) and six velocities (0°/s, 30°/s, 60°/s, 90°/s, 120°/s and 180°/s) in 53 healthy adults. These data were used to generate 3D plots, or "strength surfaces", for males and females for each direction; surfaces were fit using a logistic equation. We also tested predictors of ankle strength, including height, weight, sex, and self-reported physical activity levels.
Results: Torque-velocity and torque-angle relationships at the ankle interact, indicating that these relationships are interdependent and best modeled using 3D surfaces. Sex was the strongest predictor of ankle strength over height, weight, and self-reported physical activity levels. 79 to 97 % of the variance in mean peak torque was explained by joint angle and movement velocity using logistic equations, for men and women and PF and DF directions separately.
Conclusions: The 3D strength data and surface models provide a more comprehensive dataset of ankle strength in healthy adults than previously reported. These models may allow researchers and clinicians to quantify ankle strength deficits and track recovery in patient populations, using angle- and velocity-specific ankle strength values and/or strength percentiles from healthy adults.
Details
- Title: Subtitle
- 3D strength surfaces for ankle plantar- and dorsi-flexion in healthy adults: an isometric and isokinetic dynamometry study
- Creators
- Sara J Hussain - Department of Health and Human Physiology, The University of Iowa, E102 Field House, Iowa City, IA 52242 USALaura Frey-Law - Department of Physical Therapy and Rehabilitation Science, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA 52242 USA
- Resource Type
- Journal article
- Publication Details
- Journal of foot and ankle research, Vol.9(1), pp.43-43
- DOI
- 10.1186/s13047-016-0174-1
- PMID
- 27843491
- PMCID
- PMC5105238
- NLM abbreviation
- J Foot Ankle Res
- ISSN
- 1757-1146
- eISSN
- 1757-1146
- Publisher
- BioMed Central; London
- Grant note
- ICRU fellowship / ; K01 AR056134 / ;
- Language
- English
- Date published
- 11/10/2016
- Academic Unit
- Nursing; Physical Therapy and Rehabilitation Science; Health, Sport, and Human Physiology
- Record Identifier
- 9984047676202771
Metrics
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