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 ?
De Quervain's tendonitis is a condition that affects the tendons in the wrist near the base of the thumb.
When patellar tendons with PT are imaged, the sonogram typically reveals an abnormal tendon with localized widening at the point of tenderness with hypoechoic areas and can show neovascularization with increased vascular flow (Fig.
The data demonstrates that Orthocell's novel technology for repairing tendons was a safe and effective procedure that enables a reduction in pain and repairs tendon in severe chronic resistant tendon injury, like tennis elbow.
A partially torn tendon may make it difficult to raise the arm, while a completely torn tendon may make it impossible.
Due to all these factors, it becomes commonly used donor tendon by hand surgeons, second stage tendon reconstruction as well as tendon grafting.
Trainer Paul Young added: "He'll have the tendon removed on Tuesday and should make a full recovery.
The bulky belly converges on a short, flat and wide tendon, which inserts on the lateral surface of trochanter femoris.
In the literature, the effect of exercise training on tendon structure was evaluated in human (healthy subjects and athletes) and animal studies, however, results were controversial.
The Achilles tendon were severed completely in longitudinal fashion and splitted using B.
The short head arises by a thick flattened tendon from the apex of the coracoid process and the long head arises from the supraglenoid tuberosity at the upper margin of the glenoid cavity, and is continuous with the glenoid labrum.
Subcutaneous tendon rupture of the peroneus longus tendon is rare disorder compared with tendinopathy of the peroneus longus tendon in sport activities.
I am suffering from tendonosis in the left Achilles tendon.