Why can the hand move flexibly?
1. Learn the structure of the hand
Basically, the hand will have 3 parts: palm, back of hand, fingers (including index finger, middle finger, ring finger, little finger and thumb).
In order for the hand to be able to do the right function, to fulfill the human requirements, the hand will rely on its muscles. These are the flexor and the extensor muscles. The muscles that govern flexion of the fingers originate from the medial side of the underarm and partially from the forearm. The muscles that govern finger extension originate from the lateral side of the underarm and partially from the forearm
The muscles do not extend toward the fingers. It is the action of the muscles on the ligaments in the fingers that cause the movement. Besides, the hand also has 37 muscles that help to move the fingers, including extrinsic and intrinsic muscles located in the hand. extrinsic muscles are the muscles that arise from the forearm and lower arm. Extrinsic muscles include 18 muscles and intrinsic muscles include 19 muscles in the hand (4 femoris, 3 lama, 4 worms and 8 inteross).
Hand muscles are very strong, so many people can climb vertical surfaces using only the force of his fingers to support his body weight.
Not only that, the hand also has a knuckle, thanks to the flexibility of this part, you can perform complex operations with ease. In addition, the knuckles also make it easier and more agile to release or grip objects in the palm of your hand or perform other gestures that require flexibility.
Your hand will contain joints to make bridges between the parts of the hand including: The joints of the hand bones, the joints between the bones of the fingers, the intervertebral joints of the wrist and wrist.
You feel cold when you touch ice, feel hot when you touch boiling water,... and did you know that the nerves of your hand will help you feel all the properties around you. The hand is a collection of medial nerves and afferent nerves. In terms of senses, the medial nerves supply activities and senses to the lateral surfaces of the thumb, middle finger, index finger, and half of the ring finger. Meanwhile, the afferent nerves provide sensory and motor activity in the skin on the back of the hand, starting from the thumb to the little finger. At the same time, they will increase sensation in the skin area right at the dorsal surface of the middle finger, index finger and half of the ring finger to the proximal intercranial joints.
To make a perfect hand as well as protect the internal organs and structures, the skin of the hand will take care of this function and as you can see, the color of the skin on the palm is lighter than the back of the hand. hands and the rest of the body.
Did you know the hand has a feature that will set you apart from others? That is, I own fingerprints - a unique DNA imprint that makes individuals different. In addition, hands are extremely sensitive.
2. Function of fingers in hand
Next is the index finger, middle finger, ring finger and little finger. They can only rotate 45 degrees, while I - the thumbs of both hands can easily rotate 90 degrees and hold the position opposite the rest of the fingers.
Next, the hand has the ability to adapt to human functional requirements. I will work with you to create a lot of new, creative and meaningful things for life, in short, will help you develop your intellect in the best way.
Have you ever been asked if you are left-brained or right-brained? Each of my hands will be controlled and operated by an opposing hemisphere of the brain. So which hand you are (right or left) can help to clearly reflect your individual biology.
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