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Bones of the face and body

Skeletal system

Bone is the hardest structure in the body; it protects the underlying structures and supports the softer tissues. The bones also give shape to the body. Internal organs are suspended from some of these bone structures, which keep them securely in position.

Some of the internal organs are surrounded with a cage of bone that protects them. Bone also provides an attachment point for the muscles, which therefore allow movement. Many blood cells are made inside the bone – this is known as bone marrow.

Bones tend to be different shapes according to what they do.

 The shape and structure of the head

The shape of the face and head are largely determined by:

  1. the bone structure of the skull
  2. the muscles covering the bones of the face.

The brain is protected by the skull. The skull consists of two parts – the cranium and the face. There are eight bones in the cranium and fourteen in the face. The only movable bone in the skull is the lower jaw (mandible).

Bones of the head

Bones of the face and upper torso powerpoint

Cranium

There are eight flat bones forming the cranium, which surrounds the brain. They are held together by connective tissue. These bones are slightly curved and are thin.

The frontal bone – forehead

This forms the front part of the roof of the skull, the forehead and the upper wall of the eye sockets.

 The two parietal bones – the crown

These form the sides and roof of the cranium.

The two temporal bones – sides of the head

These form the lower region and sides of the cranium, around the ears.

The occipital bones – lower part of cranium

This forms the back and base of the cranium. Contains a large hole (foramen magnum) the spinal cord, blood vessels and nerves pass through.

The sphenoid – back of eye sockets

This forms the anterior part of the cranium base. It is bat shaped with wings on either side forming the temples.

The ethmid bones – between eye sockets

This forms the part of the nasal cavities.

Bones of the face

The face (14)

The facial bones form the facial features, as well as support structures such as the teeth and eyes.

  • The two nasal bones – nose

These bones form the bridge of the nose.

  • The two maxillae – upper jaw

These form the upper jaw, the side walls of the nose and part of the roof of the mouth.

  • The two palatine bones – nose

These form the side walls of the nose and its walls, and the roof of the mouth.

  • The two lacrimal bones – eye sockets

These form the inner walls of the eye socket (contains a small groove for the eye socket).

  • The two nasal bones – nose

These form the bridge of the nose.

  • The two turbinate bones – nose

These form the outside of the nose.

  • The vomer bone (1) – nose

This forms part of the nasal septum (the dividing bony wall of the nose).

  • The mandible (1) – lower jaw

This is the only movable facial bone and forms the lower jaw (this is the strongest and largest facial bone).

Bones of the neck, chest, shoulder and back

The hyoid (1) – U shaped bone at the front of the neck

This supports the tongue.

Clavicle (2) 

The collar bone base of the neck, long slender bones.

These allow movement of the shoulder forming a joint with the scapula and sternum bones.

Scapula (2)

Shoulder blade bones in the upper back triangular shaped.

This provides attachment for muscles in order to move the arm. The shoulder girdle allows movement at the shoulder. This is composed of the scapulae and the clavicle.

The vertabrae

The spinal column extends from the skull down to the pelvis it provides the body with a central flexible axis.

It also protects the nerve pathway of the spinal cord, provides a surface for muscle attachments.

The vertebrae is made up of 33 bones which are all irregular and individual. As the bottom of the vertebrae, the sacrum and coccyx are fused together, there are only 24 movable bones; they consist of:

The cervical vertebrae (7) – neck

This is the part of the vertebrae which forms the top of the spine. The ATLAS – the first vertebrae supports the skull, the second vertebrae – AXIS allows the head to rotate.

Thoracic vertebrae (12)

These lay mid spine, in the thorax region, where they articulate with the ribs.

Lumbar vertabrae (5)

These help to support the body weight and are positioned in the lower region of the back.

Sacral vertebra (5)

These lay in-between the bones of the pelvis, and the bones are fused together.

The sacrum contains holes (8), blood vessels and nerves run through these.

Coccyx vertabrae (4)

This is known as the tail bone as the bones are fused together.

Thorax

This part is enclosed by ribs, which protect the lungs and heart.

It consists of the ribs, sternum and the thoracic vertebrae.

Sternum

This is the breast bone.

This is a surface for muscle attachment, also supporting muscle movements. Protects the internal organs.

The ribs

Composed of 12 pairs of ribs.

Posterior- meaning at the back of the body

They articulate with the vertebrae of the thoracic.

Anterior- meaning at the front of the body 

The first 10 ribs are attached to the sternum directly; the last three are attached indirectly and are known as false ribs, as they have no attachment anteriorly.

Pelvic girdle

The pelvic girdle supports the vertebrae and the body’s weight. It also protects some of the organs, such as the uterus. This is composed of two hip bones; at the back they are joined by the sacrum and at the front they are joined to the symphysis pubis.

The upper limbs

Humerus

Two bones in the upper arm. Together the humerus and the scapulae form the ball and socket joint, allowing movement in all directions.

Ulna and radius

These are the long bones of the forearm; they are tied together by a fibrous ring, allowing a rotating movement. The radius is shorter than the ulna bone and is positioned on the thumb side of the forearm. The ulna is positioned on the little finger side.

Wrist

This contains the Carpals. These are eight irregular sized bones which are held in place by ligaments and are very close together.

Hand

Five metacarpals, these make up the palm of the hand.

14 Phalanges, which make up the fingers – two in each thumb and three in each finger.

Lower limbs

The femur is the longest bone in the body. The head of the bone head fits into the pelvis socket, which forms the hip joint, the distal end articulates with the knee cap.

The bones of the lower leg are the Tibia (this is positioned on the lateral side of the body) and Fibula, both these have joints at the knee and at the ankle. The tibia is the larger of the two bones and carries the weight of the body.

Foot

The foot is composed of seven Tarsal bones, five metatarsal bones and 14 phalanges. These fit together to form the arches, which absorb the impact when running, jumping and walking, and they also support the foot.