1. Chapter 4: Axial & Appendicular Skeletal Anatomy Waggy
Anatomy & Physiology
Chapter 4: Axial &
Appendicular
Skeletal Anatomy
Waggy

2. Axial Skeleton Consists of: 1. Skull Eight cranial bones
14 bones of face
2. Thoracic Cage (Ribs & Sternum)
3. Spinal column

3. Skull Skull formed by 2 sets of bones
1. Cranium – encloses & protects brain.
2. Facial bones – holds eyes in anterior position & allows the facial muscles to show emotions.
All but 1 of the bones of skull are joined by sutures (interlocking, immovable joints)
Mandible attached by a freely moving joint.

4. 1. Cranium Made up of 8 large flat bones
1. Frontal – forms forehead, brow bone, superior eye orbit
2&3 Parietal (2) – form most of the superior & lateral walls of the cranium
Meet in midline = sagittal suture
Meet frontal = coronal suture
4&5. Temporal (2) – inferior to parietals & join at the squamous sutures

5. Important bone markings found on temporal bones:
External acoustic (auditory) meatus – canal leading to eardrum
Styloid process - projection inferior to external auditory meatus
Zygomatic process – thin bone that joins w/ the zygomatic (cheek) bone
Mastoid process – rough projection posterior & inferior to the external auditory meatus
Jugular foramen – junction of occipital & temporal; Allows for passage of jugular vein
Internal auditory meatus – anterior to jugular foramen
Carotid foramen - anterior to jugular foramen; Carotid artery runs through it to brain

6. Occipital – most posterior bone of cranium
-Joins parietals anteriorly at lambdoidal suture
-Foramen magnum - large opening in base of the occipitals (spinal cord connects with the brain)
-Lateral to the foramen magnum are occipital condyles

7. 7. Sphenoid – butterfly-shaped – spans the width of the skull and forms part of cranial cavity floor
Sella turcica - small depression on the midline of the sphenoid, holds the pituitary gland
Foramen ovale - large oval opening in line w/ the posterior end of the sella turcica
Parts of the sphenoid form part of the eye orbits

8. 8. Ethmoid – irregularly shaped, anterior to sphenoid – forms roof of nasal cavity and medial walls of the orbits.
Crista galli -Cock’s comb = superior ethmoid surface projection – outermost brain covering attaches
Cribriform plates – holey areas nerve fibers for smell pass through from nose

9. The 14 Facial Bones 12 paired, only the mandible and vomer are single
1&2. Maxillae (2) / maxillary bones – fused to form upper jaw
Palatine processes- extensions that form the anterior part of the hard palate
Paranasal Sinuses – drain the nasal passages, lighten the skull bones, amplify sounds as we speak
Sinusitis (infection of sinuses) – can result in headache or upper jaw pain

10. Facial Bones
3&4. Palatine(2) – posterior to palatine processes of maxillae – form posterior part of hard palate
cleft palate= failure of these to fuse
5&6. Zygomatic (2) – cheek bones
7&8. Lacrimal (2) – fingernail sized bones forming part of medial walls of orbits
serves as passageway for tears
9&10. Nasal (2)–form bridge of nose – lower part of nose made of cartilage

11. Facial Bones 11. Vomer Plow(1) forms most of the nasal septum
12. Mandible (lower jaw) – largest, strongest bone of the face –only freely movable joints in the skull
13& 14. Inferior Nasal concha - air moves through these as breathing to warm, moisten & filter it before reaching lungs

12. Thoracic Cage Sternum: fusion of three bones Manubrium Body
Xiphoid Process

13. Ribs: 12 pairs, grouped by structure
True: 1-7 attach directly to sternum via cartilage
False: 8-12 do not attach to sternum directly
Vertebrochondral: 8-10, fused together by cartilage
Floating:11-12, special type of false

14. Vertebral Column 24 vertebrae, sacrum and coccyx (26 total)
Five regions
7 cervical
12 thoracic
5 lumbar
Sacral: 5 fused bones
Coccygeal:3 to five fused bones

15. Appendicular Skeleton
Consists of:
Pectoral girdle
Arm bones
Pelvis
Formed of three fused bones
Ilium
Large, flared upper bone
Leg bones

16. Pectoral Girdle Joins the arms to the body
Made of 2 clavicles and 2 scapula

17. The Arm
Made of the humerus (upper arm), radius, ulna (lower arm) and carpel bones (hand)
Humerus -Joins the pectoral girdle at the scapula & joins the radius at the capitulum & the ulna at the trochlea

18. Lower Arm Radius Thumb side of the forearm Ulna Longer than the radius
Pinkie side of forearm

19. The Hand
Wrist: 8 carpel bones
Hand: 5 metacarpels
Fingers: 3 phalanges in each finger except the thumb (only 2 phalanges) total of 14 bones

20. Pelvic Girdle Joins the legs to the body and protects organs
Each hip is made of 3 bones: ilium, ischium, and pubis
Ilium: largest, superior portion of hip bone, joins to the sacrum
Ischium: L shaped portion, supports weight when sitting
Pubis: anterior portion of hip

21. The Leg Made of femur, patella, tibia, fibula, ankle, and foot.
Femur: thighbone, longest and heaviest in body
Joins to pelvis at acetabulum
Joins with tibia at medial and lateral condyles
Patella: covers tendon over knee

22. Lower Leg Tibia Fibula Shinbone; joins to femur and bones of ankle
Thinner than the tibia
On the lateral side of the leg

23. The Foot Ankle: made of 7 tarsal bones
Talus: tarsal that joins with the tibia and fibula
Calcaneus: heel bone, supports body weight, where Achilles tendon attaches
Foot: 5 metatarsals
Toes: Each has 3 phalanges except big toe (only 2 phalanges)

24. The End