Tendons - Extension of the Muscles its Functions, Structure and Disorder

Tendons, an extension of the muscles

Dr.Surya Rao Poodipeddi profile Authored by Dr.Surya Rao Poodipeddi on 31 Jan 2014 - 15:21.
A muscle is connected to the bone by means of a very tough but flexible band of fibrous tissue called tendon. All the skeletal muscles in the human body are responsible for moving the bones enabling us to walk, jump, lift and move in many ways like forwards,backwards and sideways.
In order to appreciate the function of a tendon one should understand the function of a skeletal muscle and how it accomplishes its functions. A muscle is a mass of muscle fibers of different shapes and sizes.
Functions of the muscle:The muscle derives its name in accordance with its shape like deltoid or trapezium. Some muscles are named after its functions. Whatever the shape or size of these muscles, the primary function of a muscle is to perform movements of limbs and other bony structures like the neck and spine.
The muscle is always located above a joint and the muscle belly tapers into a flexible and tough band of fibrous tissue called a tendon which proceeds below the concerned joint and attaches itself firmly to the bone below. Each muscle has a rich supply of nerves and blood. It gets orders from the brain to act at once depending on the function needed.
Imagine yourself bitten by an ant on the abdomen area. Immediate messages are sent to the particular muscles needed to perform the act of the hand reaching the ant and removing it. To do this several muscles come together into playing their role.  The forearm has to bend over the elbow to pick the ant from the abdomen. A muscle called biceps in the arm above the elbow, which tapers down to a tendon, which attaches to the bone in the forearm contracting it. The tendon of the muscle pulls the forearm up while the counter muscle in the back of the arm relaxes permitting the bending movement. 
Tendon structure: The tendon is an extension of a muscle that extends into a strong flexible fibrous band, that helps in accomplishing either a flexion movement (forward bending) or an extension movement (backward movement) as the connecting muscle contracts or relaxes.
The tendons have various sizes and shapes. Some are very small like those involved in the movements of the fingers and toes. And some are very long and large like in the case of Achilles tendon.

The tendons are well protected by a sheath surrounding the tendon. The sheath enables the tendon to glide smoothly as it moves the bone to which it is attached. Sometimes the sheath gets inflamed and the tendon gets swollen.  
Tendon disorders:In majority of cases the tendon whether big or small gets inflamed leading to painful movements of the tendon when required to move a joint. Such a condition is called tendonitis, which literally means inflamed tendon.
Tendonitis is caused mainly due to overuse of a joint. In most of the exercises we do, the tendon which is not used to its rigorous use, gets swollen resulting in tendonitis. Another important cause for tendonitis is  the changes that occur in the tendon due to advancing age. As people get older the tendon loses its glistening texture and cannot glide as smoothly as it was earlier.

Though the reason for such age related changes is not fully understood it is believed that some changes in the blood vessels supplying nutrition play an important role. Sometimes the tendon gets inflamed because of some anatomical anomalies when a surgical correction becomes mandatory.
The following are the tips to relieve from the discomfort of Tendonitis:
Avoiding movements which aggravate the pain, and resting the part for a considerable    duration helps to rest the tendon and reduce the swelling.
Steroids and anti-inflammatory tablets and ointments help reduce the pain and swelling.
Physiotherapy & ultrasound therapy may be needed in severe tendonitis.
The most important step to avoid tendonitis is to avoid sudden rigorous activity of any nature. Always indulge in gradual phased activity or exercise. 
In some cases the problem may recur after successful treatment. In such cases you must follow a judicious plan of activity.
A famous archer shot his arrow, which hit exactly on the back of the heel over a tendon from the muscle in the leg. The victim fell down unable to use his foot. Since then the tendon is named after the archer as Achilles tendon. This warns us to be careful in avoiding accidental injury to this all-important tendon.
*Disclaimer: This is not medical advice. The content is for educational purposes only. Please contact your doctor for any health care issues.