Реферат: The Human Hand Essay Research Paper Without

The Human Hand Essay, Research Paper

Without the hand, it would be almost impossible for the world to be the way it is

today. The importance of this body part is extremely essential for humans to survive. The

hand helps to perform in everyday tasks such as opening a Coke bottle or writing a

research paper. This is probably one of the most important body parts of the human body.

Without the hand, humans would be unable to make and use the tools which led them into

the age of today.

The human hand is made up of 27 different bones. Eight carpal bones which make

up the wrist. Five metacarpal bones that make up the palm. And fourteen phalangees

which make up the fingers. The Carpal bones are arranged in two rows of four. The row

nearest the forearm is called the proximal row. The row nearest the palm is called the

distal row. The carpal bones are small, cube-shaped, and each has six sides except for the

pisiform, which has five sides. The metacarpal bones are the five long bones of the palm.

They are named the first, second, third, fourth and fifth Metacarpal, the first being the one

leading to the thumb. The Phalangees are the bones of the fingers. Each finger contains

three, while the thumb has two.

There are twelve different muscles of the hand which are divided into three

different groups. The muscles of the thumb make up the Thenar Eminence. The muscles

that form the other fingers (also know as baby fingers) are called the Hypothenar

Eminence. Twenty muscles from the forearm also control the hands movements. These

are the flexors, extensors, supinators, pronators. The flexors help flex the wrist and

fingers. The extensors help to extend the wrist and fingers. The supinators assist in

turning the palm upward. The pronators help turn the palm downward.

There are many different disease that can effect the hand. Some of these include

carpal tunnel syndrome, ganglion cysts, dupuytren’s contracture, and de quervain’s. Carpal

tunnel syndrome is when there is pain caused in the hand when the median nerve (a nerve

which travels through the arm to supply muscles in the forearm and hand the sensation in

the hand) is compressed by fibers of the transverse carpal ligament (a strong fibrous

ligament which runs across the junction of the palm and wrist beneath the skin). A

ganglion cyst is when a jellylike bubble fills up with fluid under the skin. Dupuytrens

contracture is a disease of the tough layer of fibrous tissue between the skin of the palm,

and the underlying flexor tendons of the fingers. Basically, the tissue on the palm side of

the hand thickens, and shrinks, and produces a tightness in the area of the hand which the

diseased tissue overlies. It is a very common problem and often arises in the hands of

middle aged people. DeQuervain’s Tenosynovitis is a specific type of this inflammation

which involves the tendons of two specific muscles on the thumb side of the hand

The hand is a very complex and important part of the body. Without it we

wouldn t be able to carry out everyday functions such as eating with a fork are typing on

the computer. The bones and muscles of the hand work together to make the function of

the hand possible.

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