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Huub Maas - One of the best experts on this subject based on the ideXlab platform.

  • Force Transmission Between the Gastrocnemius and Soleus Sub-Tendons of the Achilles Tendon in Rat
    Frontiers in bioengineering and biotechnology, 2020
    Co-Authors: Connor C Gains, Guus C Baan, Janaina C Correia, Wendy Noort, Hazel R. C. Screen, Huub Maas
    Abstract:

    The Achilles tendon (AT) is comprised of three distinct sub-tendons bound together by the inter-subtendon matrix (ISTM). The interactions between sub-tendons will have important implications for AT function. The aim of this study was to investigate the extent to which the ISTM facilitates relative sliding between sub-tendons, and serves as a pathway for Force Transmission between the gastrocnemius (GAS) and soleus (SOL) sub-tendons of the rat AT. In this study, ATs were harvested from Wistar rats, and the mechanical behavior and composition of the ISTM were explored. To determine Force Transmission between sub-tendons, the proximal and distal ends of the GAS and SOL sub-tendons were secured, and the Forces at each of these locations were measured during proximal loading of the GAS. To determine the ISTM mechanical behavior, only the proximal GAS and distal SOL were secured, and the ISTM was loaded in shear. Finally, for compositional analysis, histological examination assessed the distribution of matrix proteins throughout sub-tendons and the ISTM. The results revealed distinct differences between the Forces at the proximal and distal ends of both sub-tendons when proximal loading was applied to the GAS, indicating Force Transmission between GAS and SOL sub-tendons. Inter-subtendon matrix tests demonstrated an extended initial low stiffness toe region to enable some sub-tendon sliding, coupled with high stiffness linear region such that Force Transmission between sub-tendons is ensured. Histological data demonstrate an enrichment of collagen III, elastin, lubricin and hyaluronic acid in the ISTM. We conclude that ISTM composition and mechanical behavior are specialized to allow some independent sub-tendon movement, whilst still ensuring capacity for Force Transmission between the sub-tendons of the AT.

  • Significance of epimuscular myofascial Force Transmission under passive muscle conditions.
    Journal of applied physiology (Bethesda Md. : 1985), 2019
    Co-Authors: Huub Maas
    Abstract:

    In the past 20 yr, Force Transmission via connective tissue linkages at the muscle belly surface, called epimuscular myofascial Force Transmission, has been studied extensively. In this article, the effects of epimuscular linkages under passive muscle conditions are reviewed. Several animal studies that included direct (invasive) measurements of Force Transmission have shown that different connective tissue structures serve as an epimuscular pathway and that these tissues have sufficient stiffness, especially at supraphysiological muscle lengths and relative positions, to transmit substantial passive Forces (up to 15% of active optimal Force). Exact values of lumped tissue stiffness for different connective tissue structures have not yet been estimated. Experiments using various imaging techniques (ultrasound, MRI, shear wave elastography) have yielded some, but weak, evidence of epimuscular myofascial Force Transmission for passive muscles in humans. At this point, the functional consequences of epimuscular pathways for muscle and joint mechanics in the intact body are still unknown. Potentially, however, these pathways may affect sensory feedback and, thereby, neuromuscular control. In addition, altered epimuscular Force Transmission in pathological conditions may also contribute to changes in passive range of joint motion.

  • A lumped stiffness model of intermuscular and extramuscular myofascial pathways of Force Transmission
    Biomechanics and modeling in mechanobiology, 2016
    Co-Authors: Michel Bernabei, Huub Maas, Jaap H. Van Dieën
    Abstract:

    Mechanical behavior of skeletal muscles is commonly modeled under the assumption of mechanical independence between individual muscles within a muscle group. Epimuscular myofascial Force Transmission via the connective tissue network surrounding a muscle challenges this assumption as it alters the Force distributed to the tendons of individual muscles. This study aimed to derive a lumped estimate of stiffness of the intermuscular and extramuscular connective tissues and to assess changes in such stiffness in response to a manipulation of the interface between adjacent muscles. Based on in situ measurements of Force Transmission in the rat plantar flexors, before and after resection of their connective tissue network, a nonlinear estimate of epimuscular myofascial stiffness was quantified and included in a multi-muscle model with lumped parameters which allows for Force Transmission depending on the relative position between the muscles in the group. Such stiffness estimate was assessed for a group with normal intermuscular connective tissues and for a group with increased connectivity, mimicking scar tissue development. The model was able to successfully predict the amount of epimuscular Force Transmission for different experimental conditions than those used to obtain the model parameters. The proposed nonlinear stiffness estimates of epimuscular pathways could be integrated in larger musculoskeletal models, to provide more accurate predictions of Force when effects of mechanical interaction or altered epimuscular connections, e.g. after surgery or injury, are substantial.

  • Force Transmission between Synergistic Skeletal Muscles through Connective Tissue Linkages
    Journal of biomedicine & biotechnology, 2010
    Co-Authors: Huub Maas, Thomas G. Sandercock
    Abstract:

    The classic view of skeletal muscle is that Force is generated within its muscle fibers and then directly transmitted in-series, usually via tendon, onto the skeleton. In contrast, recent results suggest that muscles are mechanically connected to surrounding structures and cannot be considered as independent actuators. This article will review experiments on mechanical interactions between muscles mediated by such epimuscular myofascial Force Transmission in physiological and pathological muscle conditions. In a reduced preparation, involving supraphysiological muscle conditions, it is shown that connective tissues surrounding muscles are capable of transmitting substantial Force. In more physiologically relevant conditions of intact muscles, however, it appears that the role of this myofascial pathway is small. In addition, it is hypothesized that connective tissues can serve as a safety net for traumatic events in muscle or tendon. Future studies are needed to investigate the importance of intermuscular Force Transmission during movement in health and disease.

  • are skeletal muscles independent actuators Force Transmission from soleus muscle in the cat
    Journal of Applied Physiology, 2008
    Co-Authors: Huub Maas, Thomas G. Sandercock
    Abstract:

    It is unclear if skeletal muscles act mechanically as independent actuators. The purpose of the present study was to investigate Force Transmission from soleus (SO) muscle for physiological lengths...

Thomas G. Sandercock - One of the best experts on this subject based on the ideXlab platform.

  • Force Transmission between Synergistic Skeletal Muscles through Connective Tissue Linkages
    Journal of biomedicine & biotechnology, 2010
    Co-Authors: Huub Maas, Thomas G. Sandercock
    Abstract:

    The classic view of skeletal muscle is that Force is generated within its muscle fibers and then directly transmitted in-series, usually via tendon, onto the skeleton. In contrast, recent results suggest that muscles are mechanically connected to surrounding structures and cannot be considered as independent actuators. This article will review experiments on mechanical interactions between muscles mediated by such epimuscular myofascial Force Transmission in physiological and pathological muscle conditions. In a reduced preparation, involving supraphysiological muscle conditions, it is shown that connective tissues surrounding muscles are capable of transmitting substantial Force. In more physiologically relevant conditions of intact muscles, however, it appears that the role of this myofascial pathway is small. In addition, it is hypothesized that connective tissues can serve as a safety net for traumatic events in muscle or tendon. Future studies are needed to investigate the importance of intermuscular Force Transmission during movement in health and disease.

  • are skeletal muscles independent actuators Force Transmission from soleus muscle in the cat
    Journal of Applied Physiology, 2008
    Co-Authors: Huub Maas, Thomas G. Sandercock
    Abstract:

    It is unclear if skeletal muscles act mechanically as independent actuators. The purpose of the present study was to investigate Force Transmission from soleus (SO) muscle for physiological lengths...

P.a. Huijing - One of the best experts on this subject based on the ideXlab platform.

  • THE EFFECTS OF SURGICAL APONEUROTOMY ARE NOT UNIQUE BUT MECHANICAL CONDITIONDEPENDENTDUETOMYOFASCIAL Force Transmission
    Journal of Biomechanics, 2007
    Co-Authors: Can A. Yucesoy, P.a. Huijing
    Abstract:

    INTRODUCTION In surgical aponeurotomy the intramuscular aponeurosis is cut transversely to correct movement disorders due to spastic contractures: greater length range and reduced Force is aimed at. Although the name of the intervention suggests interference with myotendinous Force Transmission exclusively, it also causes a discontinuity in the collagen reinForced extracellular matrix (cECM) [1], i.e. it interferes just as well with myofascial Force Transmission [2]. We hypothesized that (a) the mechanism of aponeurotomy is dominated by myofascial Force Transmission and (b) that, due to extramuscular myofascial Force Transmission [e.g. 3] effects of aponeurotomy may not be unique, but dependent on other conditions. The aim was to test these hypotheses.

  • Extramuscular myofascial Force Transmission for in situ rat medial gastrocnemius and plantaris muscles in progressive stages of dissection.
    The Journal of experimental biology, 2005
    Co-Authors: J M Rijkelijkhuizen, G C Baan, A De Haan, C J De Ruiter, P.a. Huijing
    Abstract:

    The aim of this study was to establish the extent of extramuscular myofascial Force Transmission for dissected rat medial gastrocnemius (GM) and plantaris (PL) muscles. Initially, this was done with GM still connected to extramuscular connective tissue (general fascia, neuro-vascular tract and compartmental fascia). Neighbouring muscles were also connected to these tissues. In a later stage, it was dissected progressively until finally a fully dissected in situ GM was obtained, for which the neuro-vascular tract (i.e. the nerves, blood vessels and the surrounding connective tissue) was the only extramuscular tissue left intact. Force of GM was measured not only at its distal tendon in progressive stages of dissection, but also at its dissected proximal tendon. In the stage where GM was still connected to extramuscular tissues, the experiments showed that up to 40.5+/-5.9% (mean +/- S.E.M.) of the Force exerted by the neighbouring PL muscle was transmitted onto the calcaneal bone, even when the PL tendon was not connected to this bone. After distal PL-tenotomy, a difference between proximally and distally measured Forces of GM constituted evidence for myofascial Force Transmission. In the fully dissected in situ GM muscle, no relevant myofascial Force Transmission occurred in the reference position (the position of the GM origin corresponding to a knee angle of 120 degrees). However, some myofascial Force Transmission occurred when the relative position of the origin of the fully dissected GM muscle was changed with respect to the neuro-vascular tract.

S M Mutuli - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of the Single Toggle Jaw Crusher Force Transmission Characteristics
    The Journal of Engineering, 2016
    Co-Authors: Moses Frank Oduori, D M Munyasi, S M Mutuli
    Abstract:

    This paper sets out to perform a static Force analysis of the single toggle jaw crusher mechanism and to obtain the Force Transmission characteristics of the mechanism. In order to obtain Force Transmission metrics that are characteristic of the structure of the mechanism, such influences as friction, dead weight, and inertia are considered to be extraneous and neglected. Equations are obtained by considering the balance of Forces at the moving joints and appropriately relating these to the input torque and the output torque. A mechanical advantage, the corresponding transmitted torque, and the variations thereof, during the cycle of motion of the mechanism, are obtained. The mechanical advantage that characterizes the mechanism is calculated as the mean value over the active crushing stroke of the mechanism. The Force Transmission characteristics can be used as criteria for the comparison of different jaw crusher mechanism designs in order to select the most suitable design for a given application. The equations obtained can also be used in estimating the Forces sustained by the components of the mechanism.

  • Analysis of the Single Toggle Jaw Crusher Force Transmission Characteristics
    The Journal of Engineering, 2016
    Co-Authors: Moses Frank Oduori, D M Munyasi, S M Mutuli
    Abstract:

    This paper sets out to perform a static Force analysis of the single toggle jaw crusher mechanism and to obtain the Force Transmission characteristics of the mechanism. In order to obtain Force Transmission metrics that are characteristic of the structure of the mechanism, such influences as friction, dead weight, and inertia are considered to be extraneous and neglected. Equations are obtained by considering the balance of Forces at the moving joints and appropriately relating these to the input torque and the output torque. A mechanical advantage, the corresponding transmitted torque, and the variations thereof, during the cycle of motion of the mechanism, are obtained. The mechanical advantage that characterizes the mechanism is calculated as the mean value over the active crushing stroke of the mechanism. The Force Transmission characteristics can be used as criteria for the comparison of different jaw crusher mechanism designs in order to select the most suitable design for a given application. The equations obtained can also be used in estimating the Forces sustained by the components of the mechanism.

L.n. Patel - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic (Forward and Inverse Force Transmission Capability) Analysis of the Stewart Platform as Robot Manipulator
    2007 International Conference on Mechatronics and Automation, 2007
    Co-Authors: J.m. Prajapati, L.n. Patel
    Abstract:

    The Stewart platform plays a central role in the group of parallel spatial mechanisms. It is advantageous to use the Stewart platform as robot manipulator, when accuracy, dynamic performance and load carrying capacity are having paramount importance. This work represents the analytical approach for evaluating the forward and inverse Force Transmission capabilities of the Stewart platform when it is functioning as a robot manipulator. For the forward and inverse Force Transmission analysis two eigenvalue problems are formulated. The necessary conditions for the maximum Force and torque, in forward Force Transmission analysis are investigated. The methodology applied for forward and inverse Force Transmission analysis is justified by taking numerical examples. Also the numerical algorithm of selecting actuator Forces is presented.