A hand is a multi-fingered, prehensile appendage located at the end of the forearm of primates such as humans, chimpanzees, monkeys, and lemurs. Koala is another vertebrate that has two opposite thumbs on each hand and fingerprints which are similar to that of humans and are often described as having hands instead of paws on their front limbs.
The human hands are considered to be the most distant part of the upper limb. It is one of the most remarkable feats of engineering and evolution. Hands are strong enough to allow people to climb anything and also they are sufficiently precise for the manipulation of some of the worlds’ smallest objects.
The skeleton feet are the very important foundation of our body and play a very important role to live a happy life. The foot is a very complex structure and it consists of 26 human skeleton foot bones, 33 joints, and more than 100 muscles, ligaments, and tendons. The unique design of the foot allows the average human to withstand the force which could be up to a hundred tons.
Among humans, the hands and feet play a very important function in body language. In this article, we are going to discuss the anatomy of the hand ankle, and feet, the skeleton hand bones, and also the human skeleton foot bones.
Structure of the Hands
The human hand has five digits which are four fingers and a thumb and together they are referred are five fingers. The hand consists of specific bones onto which many muscles are attached. The hand also has a collection of neurovascular structures which are responsible for drainage and innervation. The intrinsic muscles present in the hand are partially responsible for all its range and motion. The muscles present in the forearms project tendons towards the hand with the help of an equally complex and flexible anatomical structure called the wrist.
The densest area of nerve endings in our body is present at the fingers and they are the richest source of tactile feedback. Fingers also have the greatest positioning capability of the body as a result of this the sense of touch is associated with hands. There are many paired organs in the human body such as the eyes, feet, legs, and like all of these organs, each hand is dominantly controlled by the opposing brain hemispheres.
There are grasping appendages in many mammals and humans that are similar in the form of a hand such as the paws and claws, but these are not considered to be grasping hands. In the mammalian order of the primates, the only true grasping hands are present. At the distal end of each arm, the hands are located. All the apes are monkeys are sometimes described as having four hands as their toes are very long and the hallux is very opposable and looks more like a thumb which allows them to use the feet to use as hands.
Hands are capable of performing a variety of functions such as fine and gross motor movements. Gross motor movements allow humans to pick up objects whereas fine motor movement allows us to perform delicate tasks such as holding small objects. The word hand has been used by many anatomists to describe the appendage of digits on the forelimb. A human hand weights up to one pound or half a kilogram.
Areas of the Hand
There are four segments or the areas of a hand
The Palm or Volar: The palm is the central region of the anterior part of the and is located superficially to the metacarpus. This is the bottom portion of the body of the hand.
Fingers: Fingers are the digits that extend from the palm of the hand. The fingers make it possible for humans to grip objects which can be either large or small.
Back (Opisthenar): The back of the hand helps us to see the dorsal venous network which is a web of veins.
Wrist: The wrist is the connection point between the arm and the hand, The hand movements are possible only because of the wrist.
Each hand consists of 19 bones. The palm of the hand has five metacarpals and all the fingers except the thumb contain one proximal phalanx, one middle phalanx, and one distal phalanx. The thumb also has one proximal phalanx and a distal phalanx but does not have a middle phalanx. Each bone in the hand is connected by a series of ligaments.
There are five digits attached to the human hand with the nails fixed at the end in the place of a normal claw. All the four digits could be folded over a palm which helps in the grasping of any object.
Each finger has a colloquial name, that helps in distinguishing them from one another. Such as the index finger is called the point finger, forefinger, or the 2nd digit. The middle finger is also called the long finger or the 3rd digit. The ring finger is also called the 4th digit. The little finger is also called the pinky finger, small finger, baby finger, or the 5th digit. The thumb which is connected to the metacarpal bone and the trapezium is located on one of the sides and parallel to the arm. The only reliable way of identifying the human hand is by the presence of an opposable thumb.
The palm of the hand is known to not contain melanin, which is the skin pigment or the hair follicles. The sole of the foot is the only other place of the body that lacks both melanin and the hair follicles. Both the palm of the hand and the sole of the foot are known to have thicker skin than the other places of the body.
The diagram given below shows the areas of the human hand
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Anatomy of the Skeleton Hand Bones
The human hand is made up of many different bones, muscles, and ligaments which allows the movement and performance of any task without any difficulty.
There are three major types of bones in the hand which are very important and they are the Phalanges, Metacarpal bones, and carpal bones.
Phalanges: The phalanges are the fourteen fingers that are found in the fingers of each hand and also in the toes of each foot. Each finger has three phalanges that are the distal, middle and proximal. The thumb finger has only two phalanges as it does not have the middle phalange.
Metacarpal Bones: The metacarpal bones are the five biomes that compose the middle part of the hand.
Carpal Bones: The carpal bones are the eight bones that create the wrist. The two bones of the arm are connected to the two rows of the carpal bones which are the radius bone and the ulna bone.
There are many ligaments, muscles, tendons, and sheaths that can be found within the hand. The muscles are the structures that help in the contraction which in turn allows the movement of the bones in the hand.
The ligaments are made up of fibrous tissues that help in binding the joint of the hands together.
The tabular structures which surround the part of the fingers are the sheaths. The tendons help in connecting the muscles in the arm or the hand to the bone to allow smooth movement.
There are also arteries, veins, and nerves within the hands that provide blood flow and sensation to the hand and finger.
The diagram given below shows the human hand skeleton bones
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There are 26 bones,33 joints, and more than 100 muscles, tendons, and ligaments in each foot. These all work together to provide the balance, support, and mobility required for the foot to function properly. The foot could be divided into three categories which are the forefoot(metatarsals and phalanges), midfoot(cuboid, three cuneiforms, and the navicular), and the hindfoot(talus and calcaneus)
Human Skeleton Foot Bones
About 25% of the body bones are found in the foot. The human foot consists of 26 bones. These bones could be categorized into three groups which are the tarsal bones, metatarsal bones, and phalanges.
The diagram given below shows the skeleton feet bone
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Foot Bones and Their Anatomy
The tarsal bones are a group of seven bones that is responsible for making the rear section of the foot.
The tarsal bones include the talus or the ankle bone. The talus or the ankle bone is at the top of the foot. It helps in connecting with the tibia and the fibula bones which are present in the lower leg.
The calcaneus or the heel bone is the largest of all the tarsal bones. It plays a major role in supporting the body weight and its location is just below the talus.
The tarsals are the five bones that are responsible for forming an arch of the midfoot. The five bones of tarsals are the medial, intermediate, lateral cuneiforms, the cuboid, and the navicular.
The metatarsal bones consist of five tabular bones which are in a group and are present in the middle of the foot. These five bones connect to the tarsal bones and the phalanges.
The metatarsal bones sit in a row and they are numbers from one to five. The first bone sits closest to the arch of the foot and at the outer edge of the foot, the number five sits.
Phalanges are the bones that are present in the toes. From the second to the fifth toes. each of them contains three phalanges.
The phalanges consist of 14 bones that make up the toes. There are three phalanges in each toe and from the back of the foot to the front, the three phalanges are called the proximal base, a middle shaft, and the distal phalanges.
The big toe which is also known as the hallux contains only two phalanges and those are distal and proximal.
There are joints that are present between the metatarsals and the proximal phalanx of each toe. These joints are called metatarsal-phalangeal joints. These joints are responsible for the formation of the ball of the foot.