Adaptation after vastus lateralis denervation in rats demonstrates neural regulation of joint stresses and strains
In order to produce movements, muscles must act through joints. The translation from muscle force to limb movement is mediated by internal joint structures that permit movement in some directions but constrain it in others. Although muscle forces acting against constrained directions will not affect limb movements, such forces can cause excess stresses and strains in joint structures, leading to pain or injury. In this study, we hypothesized that the central nervous system (CNS) chooses muscle activations to avoid excess joint stresses and strains. We evaluated this hypothesis by examining adaptation strategies after selective paralysis of a muscle acting at the rat's knee. We show that the CNS compromises between restoration of task performance and regulation of joint stresses and strains. These results have significant implications to our understanding of the neural control of movements, suggesting that common theories emphasizing task performance are insufficient to explain muscle activations during behaviors.
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Article and author information
National Institutes of Health (NS086973)
- Matthew Tresch
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#IS00000628) of the Northwestern University. The protocol was approved by the Animal Care Committee of Northwestern University.
- Richard Nichols, Georgia Tech, United States
- Received: May 9, 2018
- Accepted: August 22, 2018
- Accepted Manuscript published: September 3, 2018 (version 1)
- Version of Record published: September 21, 2018 (version 2)
© 2018, Alessandro et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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