anatomy axial skeleton exam 1

What are the major components of the axial skeleton

Skull, vertebral column, and thoracic cage

What bones are included in the axial skeleton

Cranial bones, facial bones, vertebra, sacrum, coccyx, ribs, and sternum

What bones belong to the appendicular skeleton

Limbs, pectoral girdle (clavicle, scapula), and pelvic girdle (hip bones)

what are the cranial fossae and what do they contain

Anterior cranial fossa- holds frontal lobe

Middle cranial fossa- holds temporal lobes

Posterior cranial fossa- holds cerebellum and brain stem

What are the cranial bones and their articulations

Frontal- articulates with partial, nasal, maxilla

Parietal- frontal, temporal, occipital

Temporal- mandible, zygomatic

Occipital- vertebral column

Sphenoid- all cranial bones

Ethmoid- frontal, nasal, vomer

What are the four main sutures if the skull

Coronal- between frontal and parietal

Sagittal- between two parietals

Lambdoid- between parietal and occipital

Squamous- between parietal and temporal

What are the facial bones and their articulations

Maxilla- all facial bones except mandible

Mandible- temporal bones

Zygomatic- temporal, frontal, maxilla

Nasal- frontal, maxilla

Lacrimal- ethmoid, maxilla

Vomer- part of nasal septum

Palatine- posterior roof of mouth

Inferior nasal concha- lateral wall of nasal cavity

Why is the sphenoid bone called the keystone of the skull

They articulate with all other facial bones except mandible

What are the major cavities in the skull and facial bones

Orbital fossae- house the eyes

Nasal cavity- air passage, lined with mucosa

Paranasal sinuses- lighten the skull, enhance voice

What are the regions of the vertebral column and how many vertebrae are in each

Cervical 7

Thoracic 12

Lumbar 5

Sacrum 5

Coccyx 4

What are normal spinal curvatures and their functions

Cervical and lumber (concave) balance and movement

Thoracic and sacral (convex) accommodate organs

What is the function of intervertebral discs

Act as a shock absorbs and allow flexibility if the spine

What features are common to all vertebrae

Body, vertebral arch, vertebral foramen, transverse process, spinous process, and superior/inferior articular processes

How can you distinguish cervical, thoracic, and lumbar vertebrae

Cervical- is the smallest the top goes out into two

Thoracic- medium shaped looks like a giraffe

Lumbar- large body, short/blunt spinous process

What are intervertebral foramina and vertebral canals

Intervertebral foramina- openings between vertebrae for spinal nerves

Vertebral canals- continuous tunnel formed by vertebral foramina, houses spinal cord

What bones make up the thoracic cage

Thoracic vertebrae, ribs, sternum, and costal cartilages

What are the parts of the sternum

Manubrium, body, xiphoid process

What are the major landmarks of the sternum

Jugular notch- top of manubrium

Sternal angle- manubrium/body junction

Xiphisternal joint- body/xiphoid junction

What is the difference between true and false ribs

True ribs 1-7 directly attach to sternum via costal cartilage

False ribs 8-12 attach indirectly or not at all

What is unique about ribs 1 and 10-12

Rib 1- short, flat, with grooves for vessels

Ribs 10-12 single coastal facet, ribs 11-12 are floating

What causes cleft palate and what are its effects

Failure of palatine bones or maxillae to fuse, results in an opening between nasal and oral cavities, affecting speech and feeding

What are the characteristics of spinal curvature disorders

Kyphosis- exaggerated thoracic curve (hunchback)

Lordosis- exaggerated lumbar curve (swayback)

Scoliosis- lateral curvature of the spine

What is lumbar spinal stenosis

Narrowing of the vertebral canal in the lower back, compressing nerves and causing pain or weakness

Why are the fontanelles important in infants

Allow the skull compression during birth to accommodate brain growth

What are the names and locations of the fontanelles

Anterior- between frontal and parietal bones

Posterior- between parietal and occipital

Sphenoidal- at temples

Mastoid- behind the ears

Which skull bones form by intramembranous ossification

Flat bones of the skull (frontal, parietal. Occipital)

Which bones form by the endochondral ossification

Base of the skull, vertebrae, ribs

How does the skull change from birth to old age

At birth- more bones, large cranium

Childhood- bones fuse, face enlarges

Old age- bone loss, reduced facial height, sutures ossify

What age related changes occur in the axial skeleton

Discs thin, vertebrae compress , bone density decreases, curvature abnormalities may develop