Adaptive Remodeling of Achilles Tendon: A Multi-scale Computational Model

Stuart R. Young, Bruce Gardiner, Arash Mehdizadeh, Jonas Rubenson, Brian Umberger, David W. Smith

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

While it is known that musculotendon units adapt to their load environments, there is only a limited understanding of tendon adaptation in vivo. Here we develop a computational model of tendon remodeling based on the premise that mechanical damage and tenocyte-mediated tendon damage and repair processes modify the distribution of its collagen fiber lengths. We explain how these processes enable the tendon to geometrically adapt to its load conditions. Based on known biological processes, mechanical and strain-dependent proteolytic fiber damage are incorporated into our tendon model. Using a stochastic model of fiber repair, it is assumed that mechanically damaged fibers are repaired longer, whereas proteolytically damaged fibers are repaired shorter, relative to their pre-damage length. To study adaptation of tendon properties to applied load, our model musculotendon unit is a simplified three-component Hill-type model of the human Achilles-soleus unit. Our model results demonstrate that the geometric equilibrium state of the Achilles tendon can coincide with minimization of the total metabolic cost of muscle activation. The proposed tendon model independently predicts rates of collagen fiber turnover that are in general agreement with in vivo experimental measurements. While the computational model here only represents a first step in a new approach to understanding the complex process of tendon remodeling in vivo, given these findings, it appears likely that the proposed framework may itself provide a useful theoretical foundation for developing valuable qualitative and quantitative insights into tendon physiology and pathology.

Original languageEnglish (US)
Article numbere1005106
JournalPLoS computational biology
Volume12
Issue number9
DOIs
StatePublished - Sep 2016

Fingerprint

Remodeling
Achilles Tendon
Multiscale Model
Tendons
tendons
Computational Model
Fiber
Damage
Collagen
Fibers
damage
Repair
Unit
collagen
repair
Model
Physiology
Equilibrium State
Muscle
Stochastic Model

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Modeling and Simulation
  • Ecology
  • Molecular Biology
  • Genetics
  • Cellular and Molecular Neuroscience
  • Computational Theory and Mathematics

Cite this

Young, Stuart R. ; Gardiner, Bruce ; Mehdizadeh, Arash ; Rubenson, Jonas ; Umberger, Brian ; Smith, David W. / Adaptive Remodeling of Achilles Tendon : A Multi-scale Computational Model. In: PLoS computational biology. 2016 ; Vol. 12, No. 9.
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Adaptive Remodeling of Achilles Tendon : A Multi-scale Computational Model. / Young, Stuart R.; Gardiner, Bruce; Mehdizadeh, Arash; Rubenson, Jonas; Umberger, Brian; Smith, David W.

In: PLoS computational biology, Vol. 12, No. 9, e1005106, 09.2016.

Research output: Contribution to journalArticle

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