tendon


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Related to tendon: Achilles tendon

tendon,

tough cord composed of closely packed white fibers of connective tissue that serves to attach muscles to internal structures such as bones or other muscles. Sometimes when the muscle involved is thin and wide, the tendon is not a cord but a thin sheet known as an aponeurosis. The purpose of the tendon in attaching muscle to bone is to enable the power of the muscle to transfer over a distance. For example, when one wants to move a finger, specific muscles in the forearm contract and pull on ligaments that in turn pull the finger bones to produce the desired action.

Tendon

A cord connecting a muscle to another structure, often a bone. A tendon is a passive material, lengthening when the tension increases and shortening when it decreases. This characteristic contrasts with the active behavior of muscle. Away from its muscle, a tendon is a compact cord. At the muscle, it spreads into thin sheets called aponeuroses, which lie over and sometimes within the muscle belly. The large surface area of the aponeuroses allows the attachment of muscle fibers with a total cross-sectional area that is typically 50 times that of the tendon. See Muscle

Tendons are living tissues that contain cells. In adult tendons, the cells occupy only a very small proportion of the volume and have a negligible effect on the mechanical properties. Like other connective tissues, tendon depends on the protein collagen for its strength and rigidity. The arrangement of the long, thin collagenous fibers is essentially longitudinal, but incorporates a characteristic waviness known as crimp. The fibers lie within a matrix of aqueous gel. Thus, tendon is a fiber-reinforced composite (like fiberglass), but its collagen is much less stiff than the glass and its matrix is very much less stiff than the resin. See Collagen

The function of tendons is to transmit force. They allow the force from the muscle to be applied in a restricted region. For example, the main muscles of the fingers are in the forearm, with tendons to the fingertips. If the hand had to accommodate these muscles, it would be too plump to be functional. Tendon extension can also be significant in the movement of a joint. For example, the tendon which flexes a human thumb joint is about 7 in. (170 mm) long. The maximum force from its muscle stretches this tendon about 0.1 in. (2.9 mm), which corresponds to rotation of the joint through an angle of about 21°. See Joint (anatomy)

Some tendons save energy by acting as springs. In humans, the Achilles tendon reduces the energy needed for running by about 35%. This tendon is stretched during the first half of each step, storing energy which is then returned during takeoff. This elastic energy transfer involves little energy loss, whereas the equivalent work done by muscles would require metabolic energy in both stages. See Connective tissue, Muscular system

Tendon

 

a cord consisting of connective tissue; a tendon attaches a muscle to a bone and causes a contracting muscle to move. Tendons are composed of thick, strong, inelastic collagen fibers. The fibers are continuous with the muscle fibers at one end and are interwoven into the periosteum at the other end. Tendons vary in shape; those attached to long muscles are cylindrical, and those attached to transverse muscles are flattened and are termed aponeuroses. The centrum tendineum and galea aponeurotica are distinctive in shape. Some tendons, for example, those of the long flexor muscles of the fingers and toes, are surrounded by a synovial membrane that releases a fluid enabling the tendons to slide easily during motion.

Tendon function may be impaired by inflammation or injury. Diseases of the tendons and synovial bursae are treated conservatively. Surgery is indicated when tendons are ruptured as a result of injury.

tendon

[′ten·dən]
(anatomy)
A white, glistening, fibrous cord which joins a muscle to some movable structure such as a bone or cartilage; tendons permit concentration of muscle force into a small area and allow the muscle to act at a distance.
(civil engineering)
A steel bar or wire that is tensioned, anchored to formed concrete, and allowed to regain its initial length to induce compressive stress in the concrete before use.

tendon

In prestressed concrete, a steel element such as a wire, cable, bar, rod, or strand used to impart prestress to the concrete when the element is placed under tension.

tendon

a cord or band of white inelastic collagenous tissue that attaches a muscle to a bone or some other part; sinew
References in periodicals archive ?
Another study showed the main tendon splitting into two, with separate attachments to lateral and medial sides of the base of the fifth metatarsal (Verma et al., 2011).
Peroneus accessorius muscle has an origin comparable to fibularis quartus muscle, but its inserting tendon joins that of fibularis longus muscle in the sole (Standring).
Thus, search for alternative methods for managing the tendon injuries and reconstruction of enthesis site is a topic of great clinical interest9.
Researchers have focused on the use of PRP in acute phase of tendon injuries, in spite of the fact that in actual clinical practice patients with tendon injuries usually seek specialist medical attention in chronic phase of injury8.
Rupture of the distal biceps tendon represents only 3% of biceps rapture events compared to 97% at the proximal origin.
The brand started in 1989 at the Yaesu underground mall in Tokyo Station as the answer of Founder Yoshio Iwashita to the lack of affordable tendon, or a bowl of rice topped with tempura.
El tratamiento quirurgico se ha convertido en el pilar de la terapia para RTA en las ultimas decadas, principalmente debido a la informo un mayor riesgo de re-ruptura despues del tratamiento no quirurgico (14,15) La ruptura del tendon de Aquiles seguida de una reparacion quirurgica genera unos porcentajes pequenos de recidivas frente a tratamientos conservadores(5-8).
In the experimental group, microscopic observation revealed that the tendon-bone was more maturely healed, compared with the control group, which indicated that except for the nondistance suture of the tendon and bones, the tendon-bone healing also required adequate cell secretion to accelerate the generation of collagen fibers, maintain tendon strength, and reduce the probability of postoperative re-rupture.
No studies have evaluated the effects of hydration level or body temperature on tendon stiffness as assessed by myotonometric measurements.
The main idea of this study was to find out whether or not synovial fluid is effective in preventing tendon adhesion due to its high hyaluronic acid content and viscoelastic properties.
Results: There was no significant difference in the length and cross-sectional area of each tendon among three groups (F=0.26, P=0.86; F=0.09, P=0.96).
(1999) reported that the stiffness of the leg spring, including both tendon and muscle properties, is regulated according to the hopping height or frequency, and therefore affects GCT.