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Lamsfuss J, Bargmann S. Computational modeling of damage in the hierarchical microstructure of skeletal muscles. J Mech Behav Biomed Mater 2022; 134:105386. [DOI: 10.1016/j.jmbbm.2022.105386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 07/09/2022] [Accepted: 07/15/2022] [Indexed: 11/27/2022]
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2
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Lamsfuss J, Bargmann S. Skeletal muscle: Modeling the mechanical behavior by taking the hierarchical microstructure into account. J Mech Behav Biomed Mater 2021; 122:104670. [PMID: 34274750 DOI: 10.1016/j.jmbbm.2021.104670] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/05/2021] [Accepted: 06/26/2021] [Indexed: 11/28/2022]
Abstract
Skeletal muscles ensure the mobility of mammals and are complex natural fiber-matrix-composites with a hierarchical microstructure. In this work, we analyze the muscle's mechanical behavior on the level of fascicles and muscle fibers. We introduce continuum mechanics hyperelastic material models for the connective tissue endomysium and the embedded muscle fibers. The coupled electrical, chemical and mechanical processes taking place in activated contracting muscle fibers are captured including the temporal change of the activation level and the spatial propagation of the activation potential in fibers. In our model, we investigate the material behavior of fascicle, fiber and endomysium in the fiber direction and examine interactions between muscle fiber and endomysium by considering the temporal and spatial change of muscle fiber activation. In addition, a loading case of normal and shear forces is applied to analyze the fiber lifting force and the lifting height of unipennate muscles with different pennation angles. Moreover, the development of local stresses and strains in fibers and endomysium for different strains are studied. The simulation results allow to identify regions in high risk of damage. Optimal arrangements of unipennate muscle microstructure are found for either very small or very large pennation angles.
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Affiliation(s)
- Jens Lamsfuss
- Chair of Solid Mechanics, School of Mechanical and Safety Engineering, University of Wuppertal, Germany.
| | - Swantje Bargmann
- Chair of Solid Mechanics, School of Mechanical and Safety Engineering, University of Wuppertal, Germany; Wuppertal Center for Smart Materials, University of Wuppertal, Germany
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3
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Sinha U, Malis V, Chen JS, Csapo R, Kinugasa R, Narici MV, Sinha S. Role of the Extracellular Matrix in Loss of Muscle Force With Age and Unloading Using Magnetic Resonance Imaging, Biochemical Analysis, and Computational Models. Front Physiol 2020; 11:626. [PMID: 32625114 PMCID: PMC7315044 DOI: 10.3389/fphys.2020.00626] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/18/2020] [Indexed: 12/23/2022] Open
Abstract
The focus of this review is the application of advanced MRI to study the effect of aging and disuse related remodeling of the extracellular matrix (ECM) on force transmission in the human musculoskeletal system. Structural MRI includes (i) ultra-low echo times (UTE) maps to visualize and quantify the connective tissue, (ii) diffusion tensor imaging (DTI) modeling to estimate changes in muscle and ECM microstructure, and (iii) magnetization transfer contrast imaging to quantify the macromolecular fraction in muscle. Functional MRI includes dynamic acquisitions during contraction cycles enabling computation of the strain tensor to monitor muscle deformation. Further, shear strain extracted from the strain tensor may be a potential surrogate marker of lateral transmission of force. Biochemical and histological analysis of muscle biopsy samples can provide "gold-standard" validation of some of the MR findings. The review summarizes biochemical studies of ECM adaptations with age and with disuse. A brief summary of animal models is included as they provide experimental confirmation of longitudinal and lateral force transmission pathways. Computational muscle models enable exploration of force generation and force pathways and elucidate the link between structural adaptations and functional consequences. MR image findings integrated in a computational model can explain and predict subject specific functional changes to structural adaptations. Future work includes development and validation of MRI biomarkers using biochemical analysis of muscle tissue as a reference standard and potential translation of the imaging markers to the clinic to noninvasively monitor musculoskeletal disease conditions and changes consequent to rehabilitative interventions.
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Affiliation(s)
- Usha Sinha
- Department of Physics, San Diego State University, San Diego, CA, United States
| | - Vadim Malis
- Department of Physics, University of California, San Diego, San Diego, CA, United States
| | - Jiun-Shyan Chen
- Department of Structural Engineering, University of California, San Diego, San Diego, CA, United States
| | - Robert Csapo
- Research Unit for Orthopaediic Sports Medicine and Injury Prevention, ISAG, Private University for Health Sciences, Medical Informatics and Technology, Hall in Tirol, Austria
| | - Ryuta Kinugasa
- Department of Human Sciences, Kanagawa University, Yokohama, Japan.,Computational Engineering Applications Unit, Advanced Center for Computing and Communication, RIKEN, Saitama, Japan
| | - Marco Vincenzo Narici
- Institute of Physiology, Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Shantanu Sinha
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
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4
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Marcucci L, Reggiani C. Increase of resting muscle stiffness, a less considered component of age-related skeletal muscle impairment. Eur J Transl Myol 2020. [DOI: 10.4081/ejtm.2020.8982] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Elderly people perform more slowly movements of everyday life as rising from a chair, walking, and climbing stairs. This is in the first place due to the loss of muscle contractile force which is even more pronounced than the loss of muscle mass. In addition, a secondary, but not negligible, component is the rigidity or increased stiffness which requires greater effort to produce the same movement and limits the range of motion of the joints. In this short review, we discuss the possible determinants of the limitations of joint mobility in healthy elderly, starting with the age-dependent alterations of the articular structure and focusing on the increased stiffness of the skeletal muscles. Thereafter, the possible mechanisms of the increased stiffness of the muscle-tendon complex are considered, among them changes in the muscle fibers, alterations of the connective components (extracellular matrix or ECM, aponeurosis, fascia and tendon) and remodeling of the neural pattern of muscle activation with increased of antagonist co-activation.
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5
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Marcucci L, Reggiani C. Increase of resting muscle stiffness, a less considered component of age-related skeletal muscle impairment. Eur J Transl Myol 2020; 30:8982. [PMID: 32782762 PMCID: PMC7385684 DOI: 10.4081/ejtm.2019.8982] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 04/06/2020] [Indexed: 12/13/2022] Open
Abstract
Elderly people perform more slowly movements of everyday life as rising from a chair, walking, and climbing stairs. This is in the first place due to the loss of muscle contractile force which is even more pronounced than the loss of muscle mass. In addition, a secondary, but not negligible, component is the rigidity or increased stiffness which requires greater effort to produce the same movement and limits the range of motion of the joints. In this short review, we discuss the possible determinants of the limitations of joint mobility in healthy elderly, starting with the age-dependent alterations of the articular structure and focusing on the increased stiffness of the skeletal muscles. Thereafter, the possible mechanisms of the increased stiffness of the muscle-tendon complex are considered, among them changes in the muscle fibers, alterations of the connective tissue components, i.e., extracellular matrix (ECM), aponeurosis, tendon and fascia, and remodeling of the neural pattern of muscle activation that increases antagonist co-activation.
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Affiliation(s)
- Lorenzo Marcucci
- Department of Biomedical Sciences, Padova University, Padova, Italy.,Center for Mechanics of Biological Materials, Padova University, Padova, Italy.,Center for Biosystems Dynamics Research, RIKEN, Suita, Osaka, 565-0874, Japan
| | - Carlo Reggiani
- Department of Biomedical Sciences, Padova University, Padova, Italy.,Center for Mechanics of Biological Materials, Padova University, Padova, Italy.,Science and Research Centre Koper, Institute for Kinesiology Research, Koper, Slovenia
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6
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Alterations of Extracellular Matrix Mechanical Properties Contribute to Age-Related Functional Impairment of Human Skeletal Muscles. Int J Mol Sci 2020; 21:ijms21113992. [PMID: 32498422 PMCID: PMC7312402 DOI: 10.3390/ijms21113992] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/29/2020] [Accepted: 05/29/2020] [Indexed: 12/30/2022] Open
Abstract
Aging of human skeletal muscles is associated with increased passive stiffness, but it is still debated whether muscle fibers or extracellular matrix (ECM) are the determinants of such change. To answer this question, we compared the passive stress generated by elongation of fibers alone and arranged in small bundles in young healthy (Y: 21 years) and elderly (E: 67 years) subjects. The physiological range of sarcomere length (SL) 2.5-3.3 μm was explored. The area of ECM between muscle fibers was determined on transversal sections with picrosirius red, a staining specific for collagen fibers. The passive tension of fiber bundles was significantly higher in E compared to Y at all SL. However, the resistance to elongation of fibers alone was not different between the two groups, while the ECM contribution was significantly increased in E compared to Y. The proportion of muscle area occupied by ECM increased from 3.3% in Y to 8.2% in E. When the contribution of ECM to bundle tension was normalized to the fraction of area occupied by ECM, the difference disappeared. We conclude that, in human skeletal muscles, the age-related reduced compliance is due to an increased stiffness of ECM, mainly caused by collagen accumulation.
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7
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Marcucci L, Bondì M, Randazzo G, Reggiani C, Natali AN, Pavan PG. Fibre and extracellular matrix contributions to passive forces in human skeletal muscles: An experimental based constitutive law for numerical modelling of the passive element in the classical Hill-type three element model. PLoS One 2019; 14:e0224232. [PMID: 31689322 PMCID: PMC6830811 DOI: 10.1371/journal.pone.0224232] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 10/08/2019] [Indexed: 01/30/2023] Open
Abstract
The forces that allow body movement can be divided into active (generated by sarcomeric contractile proteins) and passive (sustained by intra-sarcomeric proteins, fibre cytoskeleton and extracellular matrix (ECM)). These are needed to transmit the active forces to the tendon and the skeleton. However, the relative contribution of the intra- and extra- sarcomeric components in transmitting the passive forces is still under debate. There is limited data in the literature about human muscle and so it is difficult to make predictions using multiscale models, imposing a purely phenomenological description for passive forces. In this paper, we apply a method for the experimental characterization of the passive properties of fibres and ECM to human biopsy and propose their clear separation in a Finite Element Model. Experimental data were collected on human single muscle fibres and bundles, taken from vastus lateralis muscle of elderly subjects. Both were progressively elongated to obtain two stress-strain curves which were fitted to exponential equations. The mechanical properties of the extracellular passive components in a bundle of fibres were deduced by the subtraction of the passive tension observed in single fibres from the passive tension observed in the bundle itself. Our results showed that modulus and tensile load bearing capability of ECM are higher than those of fibres and defined their quantitative characterization that can be used in macroscopic models to study their role in the transmission of forces in physiological and pathophysiological conditions.
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Affiliation(s)
- Lorenzo Marcucci
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
| | - Michela Bondì
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Giulia Randazzo
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Carlo Reggiani
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
- Kinesiology Research Center, Garibaldijeva, Koper, Slovenia
| | - Arturo N. Natali
- Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
- Department of Industrial Engineering, University of Padova, Padova, Italy
| | - Piero G. Pavan
- Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
- Department of Industrial Engineering, University of Padova, Padova, Italy
- Fondazione Istituto di Ricerca Pediatrica Città della Speranza, Corso Stati Uniti 4, Padova, Italy
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8
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Spyrou LA, Agoras M, Danas K. A homogenization model of the Voigt type for skeletal muscle. J Theor Biol 2016; 414:50-61. [PMID: 27884495 DOI: 10.1016/j.jtbi.2016.11.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 11/12/2016] [Accepted: 11/18/2016] [Indexed: 10/20/2022]
Abstract
A three-dimensional constitutive model for skeletal muscle incorporating microstructural characteristics is developed and numerically implemented in a general purpose finite element program. The proposed model takes into account explicitly the volume fractions of muscle fibers and connective tissue by using the Voigt homogenization approach to bridge the different length scales of the muscle structure. The model is used to estimate the active and passive homogenized muscle response. Next, the model is validated by experimental data and periodic three-dimensional unit cell calculations comprising various fiber volume fractions and mechanical properties of the constituents. The model is found to be in very good agreement with both the experimental data and the finite element results for all the examined cases. The influence of fiber volume fraction and material properties of constituents on effective muscle response under several loading conditions is examined.
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Affiliation(s)
- L A Spyrou
- Institute for Research & Technology - Thessaly, Centre for Research & Technology Hellas (CERTH), 38333 Volos, Greece.
| | - M Agoras
- Department of Mechanical Engineering, University of Thessaly, 38334 Volos, Greece.
| | - K Danas
- LMS, CNRS, École Polytechnique, Université Paris-Saclay, 91128 Palaiseau, France.
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9
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Szczesny SE, Elliott DM. Incorporating plasticity of the interfibrillar matrix in shear lag models is necessary to replicate the multiscale mechanics of tendon fascicles. J Mech Behav Biomed Mater 2014; 40:325-338. [PMID: 25262202 DOI: 10.1016/j.jmbbm.2014.09.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 08/26/2014] [Accepted: 09/02/2014] [Indexed: 11/18/2022]
Abstract
Despite current knowledge of tendon structure, the fundamental deformation mechanisms underlying tendon mechanics and failure are unknown. We recently showed that a shear lag model, which explicitly assumed plastic interfibrillar load transfer between discontinuous fibrils, could explain the multiscale fascicle mechanics, suggesting that fascicle yielding is due to plastic deformation of the interfibrillar matrix. However, it is unclear whether alternative physical mechanisms, such as elastic interfibrillar deformation or fibril yielding, also contribute to fascicle mechanical behavior. The objective of the current work was to determine if plasticity of the interfibrillar matrix is uniquely capable of explaining the multiscale mechanics of tendon fascicles including the tissue post-yield behavior. This was examined by comparing the predictions of a continuous fibril model and three separate shear lag models incorporating an elastic, plastic, or elastoplastic interfibrillar matrix with multiscale experimental data. The predicted effects of fibril yielding on each of these models were also considered. The results demonstrated that neither the continuous fibril model nor the elastic shear lag model can successfully predict the experimental data, even if fibril yielding is included. Only the plastic or elastoplastic shear lag models were capable of reproducing the multiscale tendon fascicle mechanics. Differences between these two models were small, although the elastoplastic model did improve the fit of the experimental data at low applied tissue strains. These findings suggest that while interfibrillar elasticity contributes to the initial stress response, plastic deformation of the interfibrillar matrix is responsible for tendon fascicle post-yield behavior. This information sheds light on the physical processes underlying tendon failure, which is essential to improve our understanding of tissue pathology and guide the development of successful repair.
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Affiliation(s)
- Spencer E Szczesny
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33rd St, Philadelphia, PA 19104, United States.
| | - Dawn M Elliott
- Department of Biomedical Engineering, University of Delaware, 125 East Delaware Avenue, Newark, DE 19716, United States.
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10
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Zhang C, Gao Y. The role of transmembrane proteins on force transmission in skeletal muscle. J Biomech 2014; 47:3232-6. [PMID: 25113807 DOI: 10.1016/j.jbiomech.2014.07.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 06/24/2014] [Accepted: 07/16/2014] [Indexed: 10/25/2022]
Abstract
Lateral transmission of force from myofibers laterally to the surrounding extracellular matrix (ECM) via the transmembrane proteins between them is impaired in old muscles. Changes in geometrical and mechanical properties of ECM of skeletal muscle do not fully explain the impaired lateral transmission with aging. The objective of this study was to determine the role of transmembrane proteins on force transmission in skeletal muscle. In this study, a 2D finite element model of single muscle fiber composed of myofiber, ECM, and the transmembrane proteins between them was developed to determine how changes in spatial density and mechanical properties of transmembrane proteins affect the force transmission in skeletal muscle. We found that force transmission and stress distribution are not affected by mechanical stiffness of the transmembrane proteins due to its non-linear stress-strain relationship. Results also showed that the muscle fiber with insufficient transmembrane proteins near the end of muscle fiber transmitted less force than that with more proteins does. Higher stress was observed in myofiber, ECM, and proteins in the muscle fiber with fewer proteins.
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Affiliation(s)
- Chi Zhang
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, 220 Upson Hall, Ithaca, NY 14853, USA
| | - Yingxin Gao
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, 220 Upson Hall, Ithaca, NY 14853, USA.
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11
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Szczesny SE, Elliott DM. Interfibrillar shear stress is the loading mechanism of collagen fibrils in tendon. Acta Biomater 2014; 10:2582-90. [PMID: 24530560 DOI: 10.1016/j.actbio.2014.01.032] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 12/04/2013] [Accepted: 01/30/2014] [Indexed: 12/15/2022]
Abstract
Despite the critical role tendons play in transmitting loads throughout the musculoskeletal system, little is known about the microstructural mechanisms underlying their mechanical function. Of particular interest is whether collagen fibrils in tendon fascicles bear load independently or if load is transferred between fibrils through interfibrillar shear forces. We conducted multiscale experimental testing and developed a microstructural shear lag model to explicitly test whether interfibrillar shear load transfer is indeed the fibrillar loading mechanism in tendon. Experimental correlations between fascicle macroscale mechanics and microscale interfibrillar sliding suggest that fibrils are discontinuous and share load. Moreover, for the first time, we demonstrate that a shear lag model can replicate the fascicle macroscale mechanics as well as predict the microscale fibrillar deformations. Since interfibrillar shear stress is the fundamental loading mechanism assumed in the model, this result provides strong evidence that load is transferred between fibrils in tendon and possibly other aligned collagenous tissues. Conclusively establishing this fibrillar loading mechanism and identifying the involved structural components should help develop repair strategies for tissue degeneration and guide the design of tissue engineered replacements.
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Affiliation(s)
- Spencer E Szczesny
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33rd St, Philadelphia, PA 19104, USA
| | - Dawn M Elliott
- Department of Biomedical Engineering, University of Delaware, 125 East Delaware Avenue, Newark, DE 19716, USA.
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12
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Knudsen AB, Larsen M, Mackey AL, Hjort M, Hansen KK, Qvortrup K, Kjaer M, Krogsgaard MR. The human myotendinous junction: an ultrastructural and 3D analysis study. Scand J Med Sci Sports 2014; 25:e116-23. [PMID: 24716465 DOI: 10.1111/sms.12221] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/21/2014] [Indexed: 11/27/2022]
Abstract
The myotendinous junction (MTJ) is a specialized structure in the musculotendinous system, where force is transmitted from muscle to tendon. Animal models have shown that the MTJ takes form of tendon finger-like processes merging with muscle tissue. The human MTJ is largely unknown and has never been described in three dimensions (3D). The aim of this study was to describe the ultrastructure of the human MTJ and render 3D reconstructions. Fourteen subjects (age 25 ± 3 years) with isolated injury of the anterior cruciate ligament (ACL), scheduled for reconstruction with a semitendinosus/gracilis graft were included. Semitendinosus and gracilis tendons were stripped as grafts for the ACL reconstruction. The MTJ was isolated from the grafts and prepared for transmission electron microscopy (TEM) and focused ion beam/scanning electron microscopy. It was possible to isolate recognizable MTJ tissue from all 14 patients. TEM images displayed similarities to observations in animals: Sarcolemmal evaginations observed as finger-like processes from the tendon and endomysium surrounding the muscle fibers, with myofilaments extending from the final Z-line of the muscle fiber merging with the tendon tissue. The 3D reconstruction revealed that tendon made ridge-like protrusions, which interdigitiated with groove-like indentations in the muscle cell.
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Affiliation(s)
- A B Knudsen
- Department of Sports Traumatology M51, Bispebjerg University Hospital, Copenhagen, Denmark
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13
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Zhang C, Gao Y. Finite element analysis of mechanics of lateral transmission of force in single muscle fiber. J Biomech 2012; 45:2001-6. [PMID: 22682257 PMCID: PMC3843153 DOI: 10.1016/j.jbiomech.2012.04.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 03/22/2012] [Accepted: 04/26/2012] [Indexed: 11/19/2022]
Abstract
Most of the myofibers in long muscles of vertebrates terminate within fascicles without reaching either end of the tendon, thus force generated in myofibers has to be transmitted laterally through the extracellular matrix (ECM) to adjacent fibers; which is defined as the lateral transmission of force in skeletal muscles. The goal of this study was to determine the mechanisms of lateral transmission of force between the myofiber and ECM. In this study, a 2D finite element model of single muscle fiber was developed to study the effects of mechanical properties of the endomysium and the tapered ends of myofiber on lateral transmission of force. Results showed that most of the force generated is transmitted near the end of the myofiber through shear to the endomysium, and the force transmitted to the end of the model increases with increased stiffness of ECM. This study also demonstrated that the tapered angle of the myofiber ends can reduce the stress concentration near the myofiber end while laterally transmitting force efficiently.
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Affiliation(s)
- Chi Zhang
- Sibley School of Mechanical and Aerospace Engineering, 220 Upson Hall, Cornell University, Ithaca, NY 14853, USA
| | - Yingxin Gao
- Sibley School of Mechanical and Aerospace Engineering, 220 Upson Hall, Cornell University, Ithaca, NY 14853, USA
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14
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Lou J, Bi W, Li W, Zhao Y, Liu S, Zheng J, Yan C. Muscle injury induced by different types of contractions in dystrophic mdx mice. J Muscle Res Cell Motil 2012; 32:411-9. [DOI: 10.1007/s10974-012-9284-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 01/31/2012] [Indexed: 02/07/2023]
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15
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Madden MC, Byrnes WC, Lebin JA, Batliner ME, Allen DL. Plasma matrix metalloproteinase-9 response to eccentric exercise of the elbow flexors. Eur J Appl Physiol 2011; 111:1795-805. [DOI: 10.1007/s00421-010-1806-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Accepted: 12/23/2010] [Indexed: 12/31/2022]
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16
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Gumerson JD, Kabaeva ZT, Davis CS, Faulkner JA, Michele DE. Soleus muscle in glycosylation-deficient muscular dystrophy is protected from contraction-induced injury. Am J Physiol Cell Physiol 2010; 299:C1430-40. [PMID: 20844247 DOI: 10.1152/ajpcell.00192.2010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The glycosylation of dystroglycan is required for its function as a high-affinity laminin receptor, and loss of dystroglycan glycosylation results in congenital muscular dystrophy. The purpose of this study was to investigate the functional defects in slow- and fast-twitch muscles of glycosylation-deficient Large(myd) mice. While a partial alteration in glycosylation of dystroglycan in heterozygous Large(myd/+) mice was not sufficient to alter muscle function, homozygous Large(myd/myd) mice demonstrated a marked reduction in specific force in both soleus and extensor digitorum longus (EDL) muscles. Although EDL muscles from Large(myd/myd) mice were highly susceptible to lengthening contraction-induced injury, Large(myd/myd) soleus muscles surprisingly showed no greater force deficit compared with wild-type soleus muscles even after five lengthening contractions. Despite no increased susceptibility to injury, Large(myd/myd) soleus muscles showed loss of dystroglycan glycosylation and laminin binding activity and dystrophic pathology. Interestingly, we show that soleus muscles have a markedly higher sarcolemma expression of β(1)-containing integrins compared with EDL and gastrocnemius muscles. Therefore, we conclude that β(1)-containing integrins play an important role as matrix receptors in protecting muscles containing slow-twitch fibers from contraction-induced injury in the absence of dystroglycan function, and that contraction-induced injury appears to be a separable phenotype from the dystrophic pathology of muscular dystrophy.
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Affiliation(s)
- Jessica D Gumerson
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109-0622, USA
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17
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Lovering RM, McMillan AB, Gullapalli RP. Location of myofiber damage in skeletal muscle after lengthening contractions. Muscle Nerve 2009; 40:589-94. [PMID: 19760787 DOI: 10.1002/mus.21389] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
High-force lengthening contractions are associated with muscle damage and pain, and the muscle-tendon junction is commonly cited as the primary area where myofiber damage occurs. We induced injury in the rat tibialis anterior muscle and acquired magnetic resonance imaging (MRI) images postinjury. We also assayed membrane damage and quantified the number of centrally nucleated myofibers throughout the injured muscles. Results suggest that myofiber injury occurs primarily in the middle portion of the muscle, with interstitial edema in the middle and distal portions.
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Affiliation(s)
- Richard M Lovering
- Department of Physiology, School of Medicine, University of Maryland, 685 West Baltimore Street, Baltimore, Maryland 21201, USA.
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