Skeletal System: Bones

tarsals

The seven bones of the ankle. The foot is made up of seven tarsals, which are irregular bones and glide over each other to provide movement.

femur

The thigh bone; this is the longest bone in the body.

thoracic spine

The thoracic spine consists of twelve vertebrae. 12 for each rib!

transverse arch

The transverse arch runs between the medial and lateral aspect of the foot and is formed by the navicular, the cuneiform bones and the bases of the five metatarsals.

lacrimal

Two lacrimal bones make up part of each eye socket.

nasals

Two nasal bones form the bridge of the nose.

palatine

Two palatine bones help make up the roof of the mouth, wall of the nasal cavity and oor of the eye sockets.

parietal

Two parietal bones form the sides and top of the skull.

temporal

Two temporal bones are found at the sides of the skull, under the parietals.

ischium

In the pelvic girdle, the ischium forms the posterior aspect of the pelvis.

pubis

Int he pelvic girdle, the pubis is situated on the anterior aspect of the pelvis. The female's pelvis is wider and shallower, and so has more space than the male's. This is because of the requirements of pregnancy and childbirth.

irregular bones

Irregular bones, such as the vertebrae of the spine, are found in places where extra strength is needed and also make good attachment points for muscles.

hyoid

It is horseshoe-shaped bone int he neck and is not joined to any other bone. However, it is attached to the temporal bone by ligaments.

ethmoid

One ethmoid bone helps to form the eye socket and nasal cavities.

frontal

One frontal bone forms the forehead.

occipital

One occipital bone forms the back of the skull.

sphenoid

One sphenoid bone helps to form the base of the skull.

vomer

One vomer extends upwards from the hard palate to make the nasal septum.

calcaneous

Tarsal 1: the heel (one bone)

coccyx

The coccyx consists of four bones fused together, knownas coccygeal bones.

ilium

The ilium is the larges tof the three bones int he pelvic girdle. The iliac crest can be felt by placing the hand on the hip.

lumbar spine

The lumbar spine consists of five bones; these are the largest vertebrae.

talus

Tarsal 2

cuboid

Tarsal 3

navicular

Tarsal 4

medial cuneiform

Tarsal 5

intermediate cuneiform

Tarsal 6

lateral cuneiform

Tarsal 7

appendicular skeleton

The appendicular skeleton is made up of the shoulder girdle, arms and hands, the pelvic bones and the legs and feet.

axial skeleton

The axial skeleton is made up of the skull, spine, ribs and sternum.

tibia

The bone situated on the anterior aspect of the lower leg, also known as the shin bone.

fibula

The bone situated on the lateral side of the tibia; it is thinner than the tibia.

carpals

The carpals consist of eight small bones in each wrist. 1: scaphoid 2: lunate 3: triquetral 4: pisiform 5: trapezium 6: trapezoid 7: capitates 8: hamates They are closely fitted together and held in position by ligaments. Tendons of muscles in the forearm cross over the wrist joint and are held close to these bones by strong fibrous bands called retinacula.

scapula

This is a large, triangular, flat bone also known as the shoulder blade. plural: scapulae

clavicle

This is a long, slender bone also known as the collar bone.

sternum

This is also known as the breast bone.

patella

This is the kneecap, which articulates with the femur.

humerus

This is the long bone of the upper arm.

cervical spine

Consists of 7 vertebrae.

flat bones

Flat bones help to protect vital organs in the body. Flat bones, such as the skull, protect the brain, and the ribs protect the heart and lungs. Other flat bones include the scapulae and the sternum.

sesamoid bones

Sesamoid bones are small, rounded bones that develop in the tendons. They enable the tendon to move smoothly over certain bones. An example is the patella, which prevents wear and tear on the tendon of the front thigh muscle, which is attached to the tibia. It keeps the tendon in place when the knee is bent. Sesamoid bones are also found in the palms of the hands and soles of the feet. For example, these bones can be found in tendons lying over the joint, under the head of the first metatarsal. Their purpose is to protect the tendon as it moves over the joint. They may vary in number from person to person and mostly measure only a few millimeters.

ribs

There are 12 pairs of ribs.

phalanges (foot)

There are 14 phalanges in each foot; these form the toes.

phalanges (hand)

There are 14 phalanges in each hand, three in each finger and two in the thumb.

metatarsals

There are five metatarsal bones in each foot.

triquetral

Carpal 3

pisiform

Carpal 4

trapezium

Carpal 5

trapezoid

Carpal 6

capitates

Carpal 7

hamates

Carpal 8

intervertebral discs

Between the bones of the spine are pads of white fibrocartilage known as intervertebral discs. The intervertebral discs are thicker in the lumbar region than in the cervical region and are kept in place by ligaments. Their functions are to act as shock absorbers and to give the spine some exibility so movement can take place.

atlas

C1

axis

C2

scaphoid

Carpal 1

lunate

Carpal 2

long bones

Long bones, such as the humerus have a long shaft and two wider ends. They act as levers to enable the body to move. Other examples of long bones include the femur, tibia, fibula, radius, ulna, metacarpals, and phalanges. A long bone has a shaft and two rounded ends, such as the bone in the femur. The shaft contains yellow bone marrow and the ends have red bone marrow. Compact bone covers them and helps provide strength. Spongy (cancellous) bone is found at each end.

short bones

Short bones are roughly cube-shaped. They are found where strength, rather than mobility, is required. Carpals and tarsals are examples of short bones.

stapes

Smallest bone in the body. Located in the inner ear.

lateral longitudinal arch

The lateral longitudinal arch is on the little-toe side of the foot and begins at the calcaneus. It rises at the cuboid and descends to the two outer metatarsal bones.

maxilla

The maxilla forms the upper part of the jaw.

medial longitudinal arch

The medial longitudinal arch is the highest arch on the big-toe side of the foot. It begins at the calcaneus, rises to the talus and descends through the navicular, the three cuneiforms and the three medial metatarsals.

metacarpals

The metacarpals consist of five metacarpal bones (long bones), which form the palm of each hand.

ulna

This bone is situated on the little-finger side of the forearm.

radius

This bone is situated on the thumb side of the forearm.

turbinate

Two turbinate bones make up part of the nasal cavity.

zygomatic

Two zygomatic bones form the cheekbones.