Bones are an important part of the human body. They give support, shape and structure to the body and perform special functions to allow movement. At birth, the body of a child has about 350 bones. As the body grows and reaches adulthood, a number of bones fuse together giving 206 bones in the adult human body.
An infant may have about 300 to 350 bones in the body but as the body develops, a number of bones fuse together leaving only 206 important bones in the adult body. Each bone performs a special role in the body and supports the movement and functions of the body parts.
The distribution of the 206 bones in the body is as follows:
• 28 bones in the skull (facial bones, ear bones and cranium)
• The horseshoe shaped hyoid bone for the neck
• 26 bones in the vertebraes (neck, thorax, sacrum, etc)
• More than 24 bones comprising of the ribs and the shoulder girdle including sternum and breastbone.
• Single pelvic girdle
• 30 bones in the arms and legs
• A few partial bones about 8 to 18 that help in making and moving the joints.
The shortest bone in the body is the stirrup, which is present in the ear. It is not more than an inch long but is important in carrying the sound from the eardrums to the inner ear. The largest bone is known as the femur, which extends from the hip to the knee. The length of the femur entirely depends on the height of the individual. The maximum number of bones is found in the arms and legs.
Human body is full of surprises. Some bones are fused together while others work independently. Some help in movement while other gives the structure. Each part is essential for the overall growth, development, and efficient function of the individual.
The axial skeleton is the head and the trunk, or anything other than the appendages. There are about 80 bones in the axial skeleton.
There are 22 bones in the skull: eight cranial bones and 14 facial bones. The cranial bones are the frontal, parietal (two), occipital, temporal (two), sphenoid and ethmoid.
The facial bones are maxilla (two), palatine (two), zygomatic (two), lacrimal (two), nasal (two), vomer, inferior nasal conchae (two) and mandible.
The inner ears contribute six bones, or three each. These are called the malleus, incus and stapes–or, in English, hammer, anvil and stirrup.
Underneath the tongue is the hyoid bone. It is often seen damaged in crime scenes when the victim died of strangulation.
The vertebral column and thoracic cage protect the heart, lungs and spinal cord. The vertebral column has 26 bones: seven cervical vertebrae, 12 thoracic vertebrae and five lumbar vertebrae. These are referred to by their numbers: C5, T8, L2, and so on. Below the lumbar vertebrae are the sacrum and coccyx, which are fused bones, but each counts as one.
The thoracic cage has 25 bones: 24 ribs and the sternum. Ribs 8 to 12 are called false ribs. This is because ribs 8 to 10 attach to the cartilage of rib 7, and ribs 11 and 12 are buried in the muscle, and are also called floating ribs.
Pectoral Girdle and Arm
The pectoral girdle consists of two scapulas (shoulder blades) and two clavicles (collar bones). The rest of the upper limb consists of 30 bones each, for a total of 60. Each appendage has the humerus, radius, ulna, eight carpal (wrist) bones, five metacarpals leading to the fingers, and 14 phalanges, or finger joints. Each finger has three phalanges, except for the thumb, which has two.
Pelvic Girdle/Lower Limb
The pelvic girdle is made up of the two os coxae, or hip bones. Each lower limb has 30 bones: the femur, patella, tibia, fibula, seven tarsals (ankle bones, including the heel bone, the calcaneus), five metatarsals and 14 phalanges. As in the hand, the great toe has two phalanges while the other digits have three.
Sesamoid bones often throw off the count of a person’s individual bones, because they can appear anywhere. These smooth, round bones often form in the knuckles of the hand. The largest and most well-known of these is the patella, or kneecap, which is formed inside the quadriceps femoris tendon.
Another type of “extra” bone is a sutural bone, which forms between the jagged sutures, or seams, of the cranial bones in the skull. There are also called wormian bones, after Danish physician Ole Worm.