Tendons structure

In particular, the gastrocnemius, or Achilles tendon structure of the domestic turkey and manner of mineralization tendon have been described... 

The end results of the chronic inflammatory changes are variable. Loss of cartilage may result in a loss of the joint space. The formation of chronic granulation or scar tissue can lead to loss of joint motion or bony fusion (called ankylosis). Laxity of tendon structures can result in a loss of support to the affected joint, leading to instabihty or subluxation. Tendon contractures also may occur, leading to chronic deformity. ... 

Vogel KG. Tendon structure and response to changing mechanical load. J Musculoskelet Neuronal Interact 2003 3 323-325. 

Figure 17.4 Schematic showing tendon size scale and tendon structure.

Concrete nuclear reactor vessels, of the order of magnitude of 15-m (50-ft) inside diameter and length, have inner linings of steel which confine the pressure. After fabrication of the liner, the tubes for the cables or wires are put in place and the concrete is poured. High-strength reinforcing steel is used. Because there are thousands of reinforcing tendons in the concrete vessel, there is a statistical factor of safety. The failure of 1 or even 10 tendons would have little effec t on the overall structure. 

One may now ask whether natural systems have the necessary structural evolution needed to incorporate high-performance properties. An attempt is made here to compare the structure of some of the advanced polymers with a few natural polymers. Figure 1 gives the cross-sectional microstructure of a liquid crystalline (LC) copolyester, an advanced polymer with high-performance applications [33]. A hierarchically ordered arrangement of fibrils can be seen. This is compared with the microstructure of a tendon [5] (Fig. 2). The complexity and higher order of molecular arrangement of natural materi-... 

Figure 2 Schematic diagram of the cross-section of tendon showing the hierarchical structural arrangement [5].

Collagen, the principal fibrous protein in mammalian tissue, has a tertiary structure made up of twisted a-helices. Three polypeptide chains, each of which is a left-handed helix, are twisted into a right-handed super helix to form an extremely strong tertiary structure. It has remarkable tensile strength, which makes it important in the structure of bones, tendons, teeth, and cartilage. 

In spite of the alteration due to deacetylation, chitosan from crab tendon possesses a crystal structure showing an orthorhombic unit cell with dimensions a = 0.828, b = 0.862 and c = 1.043 nm (fiber axis). The unit cell comprises four glucosamine units two chains pass through the unit cell with an antiparallel packing arrangement. The main hydrogen bonds are 03 05 (intramolecular) and N2 06 (intermolecular) [82]. This material has also found medical uses (below). 

The compliance in series with the active force. Force exerted by the activated elements must be transmitted or borne by whatever structural elements are in series with them. In skeletal muscle there is clearly a tendon in series but not so with smooth muscle. In smooth muscle, the total length of contractile apparatus is broken up into individual cells with intercalating extracellular connective structures. In addition, the portions of the crossbridges in series with the pulling site must also be stretched before force can rise to isometric levels. Taken together, the... 

The musculoskeletal system consists of bones, blood vessels, nerves, ligaments, tendons, muscles, and cartilage, which work together to perform the structural and kinematic functions of the organism. These musculoskeletal tissues all have a composite structure of cells embedded in a matrix produced by the cells themselves. 

Fig. 2.1.16 Trabecular bone structure, muscle after removal of the soft tissue (right). Image and tendon of a mouse tail in vitro at 21.14T, parameters multi-slice spin-echo method,...

Repetitive overuse of a tendon can cause cellular changes in the tissues. Specifically, collagenous tendon tissue is replaced with tissue that lacks the longitudinal structure of a normal tendon.16 As a result, the tendon progressively loses elasticity and its ability to handle stress or weight. This makes the tendon vulnerable to rupture or inflammation (tendonitis and tenosynovitis). 

Full-thickness skin loss with extensive damage or necrosis of muscle, bone, or supporting structures (e.g., tendon, joint, or capsule). Undermining and sinus tracts also may be present. 

As its name implies, deep somatic pain is generated in deep body structures, such as the periosteum, muscles, tendons, joints, and blood vessels. This type of pain is more diffuse than cutaneous pain. It may be elicited by strong pressure, ischemia, and tissue damage. 

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