Bones- Axial

Axial Skeleton

Axial Skeleton

Skull

Hyoid Bone

Vertebral Column

Thoracic Cage

Skull

Fontanels, Surtures

Paranasal Sinuses

Fontanels

Turn into Surtures

Soft spots

Where ossification has not occurred

Sinuses

1. Frontal

2. Ethmoid

3. Spehenoid

4. Maxillary

Cranial Bones

Frontal

Parietal

Temporal

Occipital

Sphenoid

Ethmoid

Frontal Bone

• forms forehead

• makes up top part of the orbit for eye sockets

• frontal sinuses found here

Parietal Bones

• Two total (one each side)

• sides of the head & roof of the cranial cavity

Temporal Bones

• Two total (1 each side)

• close to the ears on both sides

Temporal Bone Structures

1. Zygomatic Process

2. Mandibular Fossa

3. Mastoid Process

4. External Auditory Meatus

5. Styloid Process

Zygomatic Process

Cheekbone

Mandibular Fossa

TMJ joint

Mastoid Process

attachment for neck muscles

Mastoiditis→ ear infections

External Auditory Meatus

• opening for auditory canal to ear

Styloid Process

• sharp projections, point of attachment for several muscles of the tongue

Occipital Bone

• base of the skull

• structures to know

  -foramen magnum

  -Occipital condyles (sIts on C1)

Sphenoid Bone

• Butterfly shaped

• bottom of eye orbits with wings

• forms most of cranial base and articulates with all other cranial bones of the base

Sella Turcica

Saddle shaped structure for pituitary gland

Ethmoid Bone

Irregular shaped bone

Forms part of nasal cavity

• nasal septum

• superior and middle nasal conchae

Facial Bones

1. Zygomatic Bones

2. Maxilla Bones

3. Palatine Bones

4. Lacrimal Bones

5. Nasal Bones

6. Mandible

7. Vomer

8. Inferior Nasal Conchae Bones

Zygomatic Bones

cheekbones

Maxilla Bones

2 fuse to form

• the upper jaw

• majority of the roof of the mouth-anterior portion of the hard palate

Palatine Bones

• Form the posterior part of the hard palate

• Failure of this to fuse

  • cleft palate

Nasal Bones

• form bridge of the nose

Lacrimal Bones

• two small bones under the eye orbit

Mandible

• lower jawbone

• temporomandibular joint

• Only freely moveable joint of the skull

• muscle for chewing attached here

Vomer

• forms posterior portion of the nasal septum

Inferior Nasal Conchae

• Used to increase surface area in the nasal cavity

Hyoid Bone

• does not articulate with any other bone

• used for muscle attachments

Vertebral Column

Extends from skull to pelvis

Vertebrae are separated by cartilaginous discs

• protect spinal cord

• supporting structure for the body

• attachment for pelvic girdle

• flexibility for body

Cervical

7

Thoracic

12

Lumbar

5

Sacrum and Coccyx

bones fuse to form 1 each

Parts of Vertebra

1. Vertebral body

2. Vertebral Arch (Pedicle, Lamina)

3. Vertebral Foramen

4. Processes

   • transverse

   • articular

   • spinous

5. Intervertebral Foramen

Cervical Region

• smaller than all other vertebra

• transverse foramen

Atlas C1

• No body, depressions for occipital bone

Axis C2

Projection that fits into C1 , and acts as a pivot for rotating head

Thoracic region

• larger and stronger than cervical

• transverse processes articulate with ribs

Lumbar region

• largest and strongest bones of the vertebral column

Sacrum

• triangle shape

• 5 fused sacral bones

• foundation for pelvic girdle

Coccyx

• smaller, triangle shaped bone

• 4 fused coccygeal bones

Thoracic Cage

• sternum

• ribs

Sternum

• flat narrow bone in center

• breast bone

• contains sternoclavicular and sternocostal joints

3 parts:

1. Manubrium - superior

2. Body

3. Xiphoid Process - inferior

Ribs

12 pairs

1. True Ribs (1-7)

2. False Ribs (8-12)

3. Floating Ribs - Bottom 2, no direct attachment