Hand Anatomy

Wrist and palm anatomy is perhaps the most complex anatomy. A hand consists of several bones joined in a perfect manner, because of which we are able to eat, write, lift, type, shave, clean...etc. We can locomote our hand in many different positions. We can move our hand in various directions. The wrist joint and joints in fingers enable us to perform all types of activities. Nerves, blood vessels, muscles, bones and joints, ligaments and tendons are main parts of human hand. Bones of the hand are described below.

Anatomy of Human Hand

Human body system consists of several organs. Anatomy of organs is a complex subject, but knowing foot or hand anatomy is essential because these parts are more prone to injuries as they promote various kinds of movements. As the wrist and the hand consist of 27 bones, plastic surgeons, orthopedic surgeons and the physiotherapists require exceptional skill to treat hand fractures or injuries. Take a look at the figure below. It shows bones of the human hand.
Wrist Anatomy
The two parallel bones, the radius, and the ulna of the forearm end near the wrist joint. The fibrocartilage separates ulna from the wrist. The eight small bones of the wrist are recognized as carpal bones. The end of the forearm is connected to the hand with the help of 13 bones. The carpal bones of the wrist consist of two rows of bones, namely the proximal row containing the scaphoid, lunate, and triquetrum (beginning with the thumb side) and the distal row consisting of the trapezium, trapezoid, capitate, hamate, and pisiform bones. The eight bones, mentioned above, play an important role in the anatomy of the wrist.

Hand Anatomy
Bones of the hand (palm) are known as metacarpal bones. All five metacarpals together are recognized as the metacarpus. Wrist, palm and fingers are thus made up of several small joints. All small carpal bones join the bones lying next to them and thus make the anatomy of the human hand very complex. The bones in the fingers and thumb are known as phalanges. The metacarpals are attached to phalanges. Proximal, middle and distal are the three types of phalanges in the fingers. Proximal phalanges are present at the start of the fingers. All fingers except the thumbs (also known as pollex) have middle phalanges. Distal phalanges are present at the end of the fingers. A thumb has proximal and distal phalanges. Eight carpal bones, five metacarpals and fourteen phalanges (total 27 bones) comprise the hand.

Apart from the bones, nerves, muscles and tendons in the hand are important part of hand structure. Fingertips have dense network of nerves. Flexor retinaculum and palmar aponeurosis are the two connective tissues which are present over the carpal bones and over the long tendons of the fingers respectively. Another connective tissue known as the palmar aponeurosis plays an important role in developing the ridges in the palm, because of which we can hold objects firmly. You must have heard about carpal tunnel syndrome; which involves damaged median nerve resulting in pain in wrist and fingers or numbness in fingers. The radial and ulnar arteries provide blood to the hand. Ulnar, radial and median nerves along with the posterior antebrachial cutaneous play an important role in hand activities. A number of muscles promote extension and abduction of the wrist and fingers. They also promote flexion, supination, circumduction and pronation of the hand.

Performing hand and wrist strengthening exercises regularly can help prevent hand and wrist problems. Those who have come across hand or wrist injury, must have experienced severe unbearable pain, as hand is made up of several joints. Though surgeons study hand anatomy in detail, correcting wrist or hand fractures involves tremendous skill. Only an experienced surgeon and physiotherapist can ensure normal movement of the hand after a serious injury.