1. Chapter 7 Skeletal System
Bone Classification
Long Bones
Short Bones
Flat Bones
Irregular Bones
Sesamoid Bones
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2. Parts of a Long Bone red epiphysis- expanded end of long bone
distal
proximal
diaphysis-shaft
compact bone-outer surface
spongy bone- cancellous bone, which contain bony plates called
trabeculae. Found at the epiphysis of long bone.
medullary cavity -hollow space found in the diaphysis and spaces of spongy bone
endosteum - thin membrane lining the cavity-contains bone forming cell.
periosteum-tough, vascular membrane covering the outer surface.
marrow-
red
yellow
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3. Major parts of long bone

4. Compact and Spongy Bone
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5. Spongy bone
Location:
Flat bones, irregular bones, and end of long bones
Osteocytes- lie within the bony plates
No central canal
A layer of spongy sandwiched between plates of compact bone
In an adult, red marrow, is found in the spongy bone of all flat bones.
In an infant, red marrow occupies the cavities of long bone. Yellow marrow stores fat and fills the cavity in an adult.

6. Compact bone
In compact bone, the osteocyte's lie concentrically around a central canal. Each unit forms an osteon cemented together to form compact bone.
Central canals - contains blood vessels and nerve fibers, which provide nutrients for bone cells.
Transverse canals interconnect with the central canals, allowing communication between each osteon and the surface of bone.
Collagen gives bone strength and inorganic salts make it hard and resistant.

7. Microscopic Structure of Compact Bone
osteon
central canal
perforating canal
osteocyte
lacuna
bone matrix
canaliculus
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8. Bone Development Intramembranous Ossification
bones originate within sheetlike layers of connective tissues
broad, flat bones
skull bones (except mandible)
intramembranous bones
Endochondral Ossification
bones begin as hyaline cartilage
most bones of the skeleton
endochondral bones
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9. Endochondral Ossification
hyaline cartilage model
primary ossification center
secondary ossification centers
epiphyseal plate
osteoblasts vs. osteoclasts
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10. Growth at the Epiphyseal Plate
First layer of cells
closest to the end of epiphysis
resting cells
anchors epiphyseal plate to epiphysis
Second layer of cells
many rows of young cells
undergoing mitosis
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11. Growth at the Epiphyseal Plate
Third layer of cells
older cells
left behind when new cells appear
cells enlarging and becoming calcified
Fourth layer of cells
thin
dead cells
calcified intercellular substance
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12. Homeostasis of Bone Tissue
Bone Resorption – action of osteoclasts and parathyroid hormone
Bone Deposition – action of osteoblasts and calcitonin
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13. Factors Affecting Bone Development, Growth, and Repair
Deficiency of Vitamin A – retards bone development
Deficiency of Vitamin C – results in fragile bones
Deficiency of Vitamin D – rickets, osteomalacia
Insufficient Growth Hormone – dwarfism
Excessive Growth Hormone – gigantism, acromegaly
Insufficient Thyroid Hormone – delays bone growth
Sex Hormones – promote bone formation; stimulate ossification of epiphyseal plates
Physical Stress – stimulates bone growth
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14. Levers and Movement
7-14

15. Skeletal Organization
Axial Skeleton
head
neck
trunk
Appendicular Skeleton
upper limbs
lower limbs
pectoral girdle
pelvic girdle
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16. Skeletal Organization
7-16

17. Skull Frontal (1) forehead roof of nasal cavity roofs of orbits
frontal sinuses
supraorbital foramen
coronal suture
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18. Skull Parietal (2) side walls of cranium roof of cranium
sagittal suture
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19. Skull Temporal (2) wall of cranium floor of cranium
floors and sides of orbits
squamosal suture
external acoustic meatus
mandibular fossa
mastoid process
styloid process
zygomatic process
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20. Skull Occipital (1) back of skull base of cranium foramen magnum
occipital condyles
lambdoidal suture
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21. Skull Sphenoid (1) base of cranium sides of skull
floors and sides of orbits
sella turcica
sphenoidal sinuses
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22. Skull Ethmoid (1) roof and walls of nasal cavity floor of cranium
wall of orbits
cribiform plates
perpendicular plate
superior and middle nasal conchae
ethmoidal sinuses
crista gallis
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23. Facial Skeleton Maxillary (2) upper jaw anterior roof of mouth
floors of orbits
sides of nasal cavity
floors of nasal cavity
alveolar processes
maxillary sinuses
palatine process
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24. Facial Skeleton Palatine (2) posterior roof of mouth
floor of nasal cavity
lateral walls of nasal cavity
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25. Facial Skeleton Zygomatic (2) prominences of cheeks
lateral walls of orbits
floors of orbits
temporal process
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26. Facial Skeleton Lacrimal (2) Nasal (2) medial walls of orbits
groove from orbit to nasal cavity
Nasal (2)
bridge of nose
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27. Facial Skeleton
Vomer (1)
inferior portion of nasal septum
7-27

28. Facial Skeleton Inferior Nasal Conchae (2)
extend from lateral walls of nasal cavity
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29. Facial Skeleton Mandible (1) lower jaw body ramus mandibular condyle
coronoid process
alveolar process
mandibular foramen
mental foramen
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30. Vertebral Column cervical vertebrae C1—c7 thoracic vertebrae T1-T12
lumbar vertebrae L1-L5
sacrum S1-S5
coccyx 5-fused
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31. Vertebral Column cervical curvature thoracic curvature
lumbar curvature
pelvic curvature
rib facets
vertebra prominens
intervertebral discs
intervertebral foramina
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32. Cervical Vertebrae Atlas – 1st; supports head
Axis – 2nd; dens pivots to turn head
transverse foramina
bifid spinous processes
vertebral prominens – useful landmark
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33. Thoracic Vertebrae
long spinous processes
rib facets
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34. Lumbar Vertebrae
large bodies
thick, short spinous processes
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35. Sacrum five fused vertebrae median sacral crest dorsal sacral foramina
posterior wall of pelvic cavity
sacral promontory
7-36

36. Coccyx
tailbone
four fused vertebrae
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37. Thoracic Cage Ribs Sternum Thoracic vertebrae Costal cartilages
Supports shoulder girdle
Protects viscera
Role in breathing
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38. Ribs
True ribs (7)
False ribs (5)
floating (2)
7-39

39. Rib Structure Shaft Head – posterior end; articulates with vertebrae
Tubercle – articulates with vertebrae
Costal cartilage – hyaline cartilage
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40. Sternum
Manubrium
Body
Xiphoid process
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41. Pectoral Girdle shoulder girdle clavicles scapulae
supports upper limbs
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42. Clavicles articulate with manubrium
articulate with scapulae (acromion process)
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43. Scapulae spine supraspinous fossa infraspinous fossa acromion process
coracoid process
glenoid cavity
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44. Upper Limb
Humerus
Radius
Ulna
Carpals
Metacarpals
Phalanges
7-45

45. Humerus head greater tubercle lesser tubercle anatomical neck
surgical neck
deltoid tuberosity
capitulum
trochlea
coronoid fossa
olecranon fossa
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46. Radius lateral forearm bone head radial tuberosity styloid process
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47. Ulna medial forearm bone trochlear notch olecranon process
coronoid process
styloid process
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48. Wrist and Hand Carpals (16) Metacarpals (10) Phalanges (28) trapezium
trapezoid
capitate
scaphoid
pisiform
triquetrum
hamate
lunate
Metacarpals (10)
Phalanges (28)
proximal phalanx
middle phalanx
distal phalanx
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49. Pelvic Girdle
Coxae (2)
supports trunk of body
protects viscera
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50. Coxae hip bones ilium ischium pubis obturator foramen acetabulum
iliac crest
iliac spines
greater sciatic notch
ischium
ischial spines
lesser sciatic notch
ischial tuberosity
pubis
obturator foramen
acetabulum
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51. Greater and Lesser Pelvis
Greater Pelvis
lumbar vertebrae posteriorly
iliac bones laterally
abdominal wall anteriorly
Lesser Pelvis
sacrum and coccyx posteriorly
lower ilium, ischium, and pubis bones laterally and anteriorly
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52. Male and Female Pelvis Female iliac bones more flared broader hips
pubic arch angle greater
more distance between ischial spine and ischial tuberosity
sacral curvature shorter and flatter
lighter bones
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53. Lower Limb Femur Patella Tibia Fibula Tarsals Metatarsals Phalanges
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54. Femur longest bone of body head fovea capitis neck greater trochanter
lesser trochanter
linea aspera
condyles
epicondyles
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55. Patella kneecap anterior surface of knee
flat sesmoid bone located in a tendon
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56. Tibia shin bone medial to fibula condyles tibial tuberosity
anterior crest
medial malleolus
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57. Fibula Insert figure 7.54 lateral to tibia long, slender head
lateral malleolus
does not bear any body weight
Insert figure 7.54
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58. Ankle and Foot Tarsals (14) Metatarsals (10) Phalanges (28) calcaneus
talus
navicular
cuboid
lateral cuneiform
intermediate cuneiform
medial cuneiform
Metatarsals (10)
Phalanges (28)
proximal
middle
distal
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59. Ankle and Foot
7-60

60. Clinical Application Types of Fractures green stick fissured
comminuted
transverse
oblique
spiral
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61. Bone-Fractures Classification-type-location-direction of the fracture
Open/compound- broken through the skin
Complication-infection-osteomyelitis-delayed union
Closed-not open to the outside of the skin
Degree of the fracture-partial or complete break-
eg. Greenstick, seen in children, until age 10.
Comminuted has more than two pieces and compression fracture, involves two bones compressed together.
Impacted-fragments are wedged together-often breaks of the humerus

62. Bone Fractures
Pattern-The direction of the injury produces a pattern of fracture.
Transverse- angular forces
Spiral- results from a twisting motion
Location- Long bones, neck or head, proximal/distal
Grouped according to their etiology
sudden trauma- most common
stress trauma- wear and tear on a bone
pathologic fractures- weakened by disease

63. Bone Healing
Hematoma- Clot forms during the first 48/72 hrs after a fracture
Cellular proliferation- Involves all three layers-
Granulation tissue replace the clot
New capillary buds and fibroblast
Fibrocartilaginous callus forms distal to fracture- forming a bridge between the fragments

64. Bone healing Callus formation- cartilage forms at the site
3/4 weeks mineral salts are deposited
Ossification
Mature bone cells replace the callus, osteoclast resorb the callus-cast removed at this point
Remodeling- resorbition of excess callus fracture site becomes thicker and stronger in relation to function