Tendon from Different Anatomical Positions Essay -- Anatomy, Tissues

Structure of a tendon is made up of collagenous tissues, a fibrous protein constituted as a large portion of the organic matrix of bone and cartilage (Nordin & Frankel, 2001). Also termed extracellular matrix (ECM) consisting of few cells, 20% of cellular material is occupied as total tissue volume, whilst 80% accounts for extracellular matrix (approximately 70% water and 30% solids) (Nordin & Frankel, 2001). Contained within these solids is a ground like substance with minor components of elastin. Due to the dense interrelation tissue of collagen it is able to sustain stability over which the mechanics of the musculoskeletal system requires. This may be in the form of fibril, whereby, collagen molecules (type 1 collagen) are synthesized and secreted by fibroblasts (France , 2010). Procollagen is formed and further condensed to tropocollagen as the basic building block of collagen (France , 2010). Across the parallel network leading to the development of fibril; cross-links are formed within collagen type 1. The cross-links allow tissues to withstand strength and function under mechanical stress (Fratzl, 2008). The solids within the extracellular contain ground like substance proteoglycans (PG). PG molecules binds extracellular water of the tendons, ensuring the matrix is a hydrated-gel like material (Nordin & Frankel, 2001). Thereby the substance acts as an adhesive between microfibrils in bundles; stabilizing collagenous tissue forming connective tissue fascicles (appendix, figure 1). The functionality of tendons can be expressed by its materialization; primarily to transmit force from muscle to bone. During any form of movements the tendons encounter forces such as longitudinal, transversal and rotational (Kannus, 200... ...llagen tissue cross-links across maturation; revealing the number of cross-links decreased with growth. This suggests that a state of maturation cross-links are stabilsed to a non-reducible form (Robins et al, 1973). When stress is placed on tendons; tissue must adapt to stiffen and strengthen in response to the physical demands placed on them. Physical training during eccentric forces has been found to increase tensile strength of the tendons (Woo et al, 1981). Long periods of inactivity can disrupt the parallel structure of collagen fibers in the tendons, decrease water content, although increase collagen cross-linking (Loitz et al, 1989). The collagen turnover increases although reports suggest the amount of tendon components and overall mass is unchanged. Ultimately immobilization decreases tendon stiffness, failure load and strength (Matsumoto et al, 2003).