Hi all of my friends – today i am going describe little-bit more about Finger and Nail.I will describe also how you can care your Finger and Nail as well.
Anatomy of the fingers
The human finger is mainly a bony structure with multiple joints giving it strength and flexibility. A digit includes the hand bones but these bones are not separated into individual appendages like a finger. Instead it is contained within a single structure – the hand. Tendons attached to muscles within the hand and forearm are responsible for the different movements of the fingers.
The five fingers include :
- 1st finger – thumb (polex)
- 2nd finger – index finger (digitus secundus manus)
- 3rd finger – middle finger (digitus medius)
- 4th finger – ring finger (digitus annularis)
- 5th finger – little finger / pinky (digitus minimus manus)
There are two surfaces of the fingers :
- Palmar surface (front of the hand) continuous with the palms of the hand.
- Dorsal surface (back of the hand) containing the fingernails at the tips.
The finger bones are known as phalanges . There are 14 phalanges on each hand. All the fingers have 3 phalanges except the thumb which has 2 phalanges. Each phalanx in a finger is named according to its location :
- Proximal phalanx is the first finger bone lying next to the palm.
- Intermediate phalanx is the middle finger bone which is absent in the thumb.
- Distal phalanx is the last finger bone lying furthest away from the hand.
The hand bones are known as the metacarpals and correspond to the phalanges – the first metacarpal articulates with the proximal phalanx of the first finger.
Each phalanx has three parts – the base, shaft and head. The base of each phalanx articulates with the head of the preceding phalanx, except for the proximal phalanges (first finger bones) which articulate with the head of the metcaarpals (hand bones). The enlarged end of each phalanx (finger bone) being either the base or head is known as the knuckle bone.
There are two types of finger joints, all of which are commonly referred to as knuckle joints :
- between the finger bones – interphalangeal joints (finger-finger joint)
- between the hand bones and first finger bones – metacarpophalangeal joints (hand-finger joint)
There are two interphalangeal joints (IP joints) on each finger, except for the thumb which has one.
- The first IP joint between the proximal and intermediate phalanges is known as the proximal interphalageal joint (PIP joint).
- The second IP joint between the intermediate and distal phalanges is known as the distal interphalangeal joint (DIP joint).
There is only one metacarpophalangeal joint (MCP joint) which lies between the proximal phalanx and metacarpal (hand bone). The ends of the bones involved in the joint is lined with articular cartilage. Synovial membranes line the joint and a tough capsule surrounds the joint.
Muscles and Movements
The muscles that control the movement of the fingers are located in the forearm and hand. Tendons running from these muscles attach to various points on the finger bones. When the muscle contracts, the tendon is pulled and the finger moves at the respective joint. Therefore these muscles, although not in the finger, should be discussed briefly.
There are two ways in which the muscles controlling the fingers can be classified. The first is by location.
- Intrinsic muscles which are located in the hand. There are three groups – thenar and hypothenar, interossei and lumbrical muscles.
- Extrinsic muscles which are located in the forearm. There are two groups – extensors and flexors.
The other classification of these muscles is by the movement of the fingers.
- Flexion of the fingers where the fingers move towards the palm. The muscle groups responsible are the thenar and hypothenar (intrinsic) and the flexors in the forearm (extrinsic).
- Extension of the fingers where the fingers straighten out by moving away from the palm. The muscle groups responsible are the interossei and lumbrical muscles (intrinsic) and the extensors in the forearm (extrinsic). Volar ligaments over the palmar side of the IP joints prevents hyperextension.
Other movements like abduction where the fingers fan out, away from the middle finger, and abduction where the fingers move in towards the middle finger, are also controlled by certain intrinsic and extrinsic muscles. Circumduction is when the finger moves in a circular manner.
Nerves of the Fingers
Nerves send signals from the brain to the muscles (motor nerves) causing it to contract or from receptors in the fingers to the brain (sensory nerves) to enable the different sensations. The motor nerves supplying the muscles controlling the fingers is not discussed here since these muscles are located in the hand and forearm. It involves the median, ulnar and radial nerves.
The skin of the fingers are supplied by different nerves as follows :
- Median nerve – palmar surface, tips and nail beds of the thumb, index, middle and half of the ring fingers.
- Ulnar nerve – palmar and dorsal (back of the hand) surface of the other half of the ring finger and the little finger.
- Radial nerve – dorsal surface (excluding the tips) of the thumb, index, middle and half of the ring fingers and web between thumb and index fingers.
your writing hand
You will be using your writing hand, be it the right or the left, to perform most of your grooming.
Throughout your life, you have developed a great deal of specialization for each hand.
One hand has become the one you prefer when doing exact and delicate work.
Writing usually tops the list of such activities with its need for precision and detail, much like grooming.
Your grooming finger
When digging and cutting deep into your own skin, you want to use the most dexterous and sensitive finger you can.
Grooming is very precise and tricky work where any mistake provokes immediate pain and possibly injury.
The finger to use is the index finger of your writing hand.
It is called that way because it was used to flip index cards.
Now, I am offended by such an artificial name and prefer naming it after its natural usage; grooming.
The nail at the end of that finger is particularly important.
Avoid using that nail in any damaging way.
In my case, sensitivity is greater on the fingers of my writing hand than those on the other.
Also, my fingers decrease in sensitivity as they get farther from the index.
This creates a finger sensitivity map.
You can use fingers with less sensitivity on tasks that demand less exactness.
There are many kind of risk to broke your Finger , Your finger may be crust inside the door clutch, or may be your finger in trap in some confine work place. May be you wrongly punch somewhere and that place is containing metal or wood.
You can avoid to heart your finger to care yourself . Please use hands globes if you are working hard in metal field.
For broken finger and some others finger related problem; consult a orthopedic Doctor
Parts of the Nail
The human nail is a plate of keratin that lies on the tips of the fingers and toes. The main purpose of the nails are to protect the fingers and toes, however, the fingernail also assists with certain physical activities in daily life.
The human nail is constantly growing and being removed by clipping or biting. In childhood, it takes the nail about 3 months to grow out completely while this may take up to 6 months in the elderly.
Like any part or organ of the human body, the condition of the fingernails and toenails are dependent on the general health status. Therefore changes and defects in the nails may be indicative of certain systemic diseases.
While the word ‘nail’ is used to describe the nail bed, the entire human nail involves many other parts, some of which are not visible from the exterior.
Parts of the Nail
The matrix is the source of the cells that become the keratinized layers of the nail plate. It is located deep in the nail sinus. As new cells grow, it pushes out the nail plate replacing it with new keratin at the proximal part of the nail plate that lies adjacent to the matrix. Poor circulation, inadequate nutrition and localized or systemic diseases can affect the growth of the new cells to make up the nail plate.
The nail bed lies underneath most of the nail plate and is a continuation of the skin around the nail. It contributes to the keratin of the nail plate although it is to a lesser degree than the matrix. Blood in the dermal capillaries of the nail bed give the nail its characteristic light pink color.
This the largest part of the nail and is composed of laminated layers of keratin. It is similar in structure to human hair and skin and is made up of dead cells. The proximal edge of the nail plate is the nail root which emanates from the nail sinus. It extends across the fingers and toes to protrude from the tip (depending on the length). This free end of the nail is also known as the distal edge, while the sides are known as the lateral edges.
The nail plate is smooth and curved and light pink in color due to underlying dermal capillaries in the nail bed. Changes in the nail color may be linked to various diseases which are discussed under Discolored Nails.
At times, ridges, lines, changes in thickness and discoloration may arise as a result of disease. This is discussed further under Fingernail Ridges.
Non-pathlogical changes of the nail plate, include :
- longitudinal lines or ridges which occurs with age.
- beading, which is the loss of the smooth curved surface of the nail plate, may normally occur with age although severe beading may be indicative of disease.
- white dots, specks or lines on the nail plate (striae leukonychia) is a sign of airspaces within the nail plate and is not related to a calcium deficiency.
- The nail folds surround and supports the nail plate on all 3 sides. It is the junction of the skin and nail plate and may sometimes be slightly darker in color thereby forming a clearly demarcated margin from the surrounding skin.
- The proximal fold lies over the nail root and matrix. The lateral nail folds extend from the proximal folds and runs alongside the nail plate to terminate near the tip of the finger or toe.
- The most distal part of the lateral nail fold is often prone to trauma from mechanical injury, nail biting and ingrown nails as well as bacterial and fungal infections. Inflammation and swelling of the folds is known as paronychia.
- Also known as the eponychium, it is the part of the skin that overlaps onto the proximal part of the nail plate. It provides some, although minor, support for the nail plate but more importantly, the cuticle seals the nail sinus to prevent injury and infection of the nail root or matrix.
- The cuticle is usually thin, translucent and extends a short distance over the lunula or nail bed. It has neat margins. Ragged cuticles or uneven cuticles may be the sign of excessive manicuring, poor nail care with overuse of the hands or it can be a sign of certain connective tissue diseases.
- This is the crescent shaped area at the base of the nail plate and is usually pale white to light pink in color. It is an extension of matrix and if most evident on the thumb. A lunula with a pointy tip is possibly a sign of excessive manicuring.
Nails are made for grooming
Your nails are a product of evolution, they have evolved from claws.
We’ve been told we had them;
•To protect our fingertips,
•To help us pick small objects,
•To climb trees,
Well, I have a hard time picking small objects with them unless they are trimmed short.
Claws, such as those of a squirrel, seem quite appropriate for climbing.
In fact, humans didn’t know why they had nails;
Nail evolution – 1 From claws to nails
Just like hooves, fingernails have evolved from the claws of reptiles.About sixty-five million years ago, a reduction in the thickness of the deep layer of the claw led to the advent of nails in the first primates.
Primates aren’t the only ones to have flat nails, some marsupials also have them. This is a good example of parallel evolution; which is the development of similarities in separate lineages. It shows that flat nails are an important goal for evolution.
Nail evolution – 2 The toilet-claw
There is an intermediate evolutionary step between claws and nails; it is called the toilet-claw. The first primates had them on the second digit of their hands and feet. Just like nails, toilet claws are made of keratin. Their shape is similar to claws, but their tip isn’t as pointed. Prosimian primates still have toilet-claws nowadays, while the nails of a few South American monkey species have reversed back to claws.
Your nails can feel
We don’t think of our nails as sensitive since we cut them painlessly. This is because the nail plate, made of hard, translucent keratin, cannot feel. Yet, below the plate lies the nail’s bed. The nail’s bed is, as you would expect, packed with nerve endings and blood vessels, giving the nails their pinkish color. Sensations received by the nail itself are amplified by this system.
Nails more sensitive than fingers? Try this comparison experiment!
While reading this, move your fingertip and nail over your clothes. You want to compare the sensations you get using :
•Just your fingertip, with those using
•Just your nail.
Pass them alternatively over the seams of the clothing and try to determine how these two probes differ.
Notice how much more detailed the nail feel is.
You can reach inside and explore the fabric’s structure.
Nails grow about ⅛ of an inch (3 mm) a month. Your nails can be too short or too long to perform adequately your grooming activities.
|Lengths needed for grooming|
|Shortest||The nail barely exceeds the top of the finger when seen from under.|
|Longest||When the nail reaches ¼ inch above the fingertip, it starts bending under the pressure.|
The grooming range
You end up keeping your nails within a grooming range.
•When your nails are too short, the sensory signals from the nail and the fingertip get mixed. Worse, the nail doesn’t extend long enough to secure any hold on the folds it passes and, of course, cannot reach the bottom of deep crevices and pits.
•Too long, nails become brittle and loose some rigidity. They get curved and crooked.
Cutting your nails
Trimming your nails with scissors or a clipper is essential if you want your grooming to be productive. You don’t want to cut them too short. They should be brought back to the briefest of the grooming range. This is a time to be very attentive. It’s so easy to go crookedly. Be especially careful not to create dents because they are hard to file off.
It is the corners of your nails that you will be using most for grooming. For this reason, I recommend not trying to give your nails a rounded style.
•Cut or clip each one with only a slight curve.
This operation leaves the corners of the nails too sharp.
•In a second operation, give a slight finishing cut on both sides of the nail.
Removing these pointy tips helps the nail flatten and makes your grooming less hazardous.
•The third step involves using a file to remove sharp edges and to perfect your work.
Some fingers are used much more than others while carrying out grooming operations. You may decide to keep some nails longer than others as your grooming technique develops or for personal reasons. Ideally, all four nails on your fingers of both hands should be kept in the grooming range. Your thumbs are optional since less than 1% of the grooming is done with them. Cutting them makes your life easier, but having them when they are needed, is quite enjoyable.
Your nails, like many other body parts, reflect your health. Keep an eye on any growing malformation. Color changes, depressions and grooves, curbing, fragility, … could be signs of health problems. With grooming, your nails become essential to your well-being and looks, as well as being indispensable in your everyday life. Take a proud care of them, wear gloves when doing risky or damaging work.
Cleaning your nails
You can usually clean the top side of your nails easily with water in a few seconds.Their shiny, smooth texture makes cleansing a breeze.It is the underside that represents a problem.Before growing longer than your fingertip, this surface was attached to the nail’s bed.It is porous and dirt is hard to clear off from it.
•To clean your nails, soap and water, with the help of your other nails, do a fine job.
•Only use a hard object, such as the tip of a file, if you need to.
•Try not to go too deep when going beneath the nail.
This area is easily hurt; it is normal that you can’t reach the bottom.
Keeping your nails clean while grooming
The nail on the finger you use to groom becomes dirty quite fast.In reality, the space beneath the blade gets filled with epidermis cells that you rake off your skin. The color of the cells that gather there depends on your natural skin tone and on how tanned you are.So, their dark coloration is no sign of uncleanness.The area can fill up in less than two minutes of grooming.The presence of litter in the gap can reduce the sensations you receive from the nail.Since it would not make sense to wash your hands every few minutes, it is best to keep a piece of facial tissue close by.
The natural nail look
Don’t apply any nail polish or try to embellish your nails in any manner.You wouldn’t want to groom with nails covered with dubious chemicals.Stop thinking of nails as useless decorations.They are naturally beautiful, with nothing added, mostly when their length is in the grooming range.
Many people have acquired uncontrolled behaviors with this part of their body.Nail biting, peeling skin removal and auto-mutilation are common practices.Continuing or stopping these practices says a lot on the control you have on yourself.Take responsibility for these actions.
Peelings around the fingernail
Though I advocate removing chapped or flaking skin in most areas of the body, the nail-fingertip junction demands special care.If you pull on the hanging peelings, you may rip the skin and hurt yourself.Cut them clean instead and groom the area very delicately.
Long nails and everyday life
I had a hard time getting used to having long nails.They make simple things, such as picking a coin, more difficult.Typing on a keyboard becomes an adventure.We need a new line of instruments made for long nail bearers.But, in any event, humans will have to adapt to life with long nails.It is part of being a primate.
A wonderful tool
Your nails are formidable tools for grooming.Sensitive and tough, they can be pressed strongly against your skin without harming it.Their shape and dimensions are just right for the task they were conceived to achieve.
Humans are branded as a tool-making race, but these have been designed by God, so they feel and grow.
Source from Internet.