1. Chapter 7: The Skeletal System

2. Outline Functions of Skeletal System Medical Terminology
Bone Structure & Formation
The Axial Skeleton
The Appendicular Skeleton
Joints
Skeletal Disorders

3. Ch. 7 Agenda Tuesday, 11/12 Thursday, 11/14 Monday, 11/18
Functions, Med Terms, Structure & Formation
Thursday, 11/14
Bones of the Axial Skeleton
Monday, 11/18
Quiz on Tuesday’s notes
Bones of Appendicular Skeleton
Wednesday, 11/20
Quiz on Axial Skeleton
Joints
Friday, 11/22
Quiz on Appendicular Skeleton
Bone Lab
Tuesday, 12/3
Skeletal Disorders
Thursday, 12/5
Review of Ch. 7
Monday, 12/9
Chapter 7 Test

4. I. Functions of the Skeletal System
Support
Protection
Protects internal organs
Produces white blood cells that protect the body from disease
Movement
Storage
Maintain homeostasis of calcium
Calcium is needed form nerve and muscle function

5. I. Functions of the Skeletal System
Hematopoiesis
The process of blood cell formation
Performed in the red bone marrow
Bone marrow is soft tissue found inside the hard walls of some bones

6. II. Medical Terminology
Prefixes
Prefix
Meaning
Example
Example Meaning 1
Infra-
Below, beneath
Infraorbital
Below the (eye) orbit 2
Inter-
Between
Intervertebral
Between vertebrae 3
Meta-
Beyond, after
Metatarsal
Beyond the tarsals 4
Peri-
Around; surrounding
Pericardium
Covering of the heart

7. II. Medical Terminology
Suffixes
Suffix
Meaning
Example
Example Meaning 1
-blast
Make
Osteoblast
Bone maker 2
-clast
Break, destroy
Osteoclast
Bone breaker

8. II. Medical Terminology
Roots
Root
Meaning
Example
Example Meaning 1
arthr-
Joint
Arthritis
Inflammation of joints 2
cerv-
Neck
Cervical
Pertaining to the neck 3
crani-
Skull
Intracanial
Within the skull 4
myel-
Marrow
Myeloma
Marrow tumor 5
osteo-
Bone
Osteoma
Bone tumor 6
poie-
Make; produce
hematopoiesis
Blood cell production

9. III. Bone Structure and Formation
Tissue Structure
Bone
Spongy or Cancellous Bone
Porous
Made up of trabeculae
Filled with red bone marrow

10. A. Tissue Structure Bone Dense or Compact Bone
Organized into structural units called osteons
Composed of calcified concentric tubes called lamellae
The lamella surround the central canal which contains blood vessels
There are also spaces between lamellae called lacunae
Within the lacunae are osteocytes
Osteocytes are connected to each other and the central canal by canaliculi
Allow for nutrients to be passed from the blood vessels of the central canal to osteocytes

12. A. Tissue Structure Cartilage
Made of a gel-like material more flexible than bone
Chondrocytes are cartilage cells suspended in the gel in lacunae
Lacks blood vessels
Nutrients diffuse through gel
Takes longer to repair after injury

13. B. Types of Bone Long Short Flat Irregular Sesamoid (round)
Example: humerus (upper arm)
Short
Ex: Carpals (wrist)
Flat
Ex: Skull bones
Irregular
Ex: vertebrae (spinal bones)
Sesamoid (round)
Ex: patella (knee cap)

15. C. Structure of Long Bone
Diaphysis (or shaft)
Hollow tube of compact bone
Medullary Cavity
The hollow area inside the diaphysis
Contains yellow marrow
Epiphyses
Ends of the bone
Contains red marrow in spongy bone

17. C. Structure of Long Bones
Articular Cartilage
A thin layer of cartilage covering each epiphysis
Cushions joints
Periosteum
Strong membrane covering a long bone
Contains blood vessels, nerves, and lymph vessels
Provides place for tendon and ligament attachment
Endosteum
Thin membrane lining medullary cavity

19. D. Structure of Flat Bones
Compact Bone
Cancellous bone
Trabeculae

20. E. Bone Formation and Growth
Most bones are formed from cartilage
In a process called endochondral ossification ( or just ossification)
Cartilage models are replaced with bone
Babies start out with as many as 270 “bones”
Adults only have 206

21. D. Bone Formation and Growth
Ossification carried out by two types of cells
Osteoblasts
Bone forming cells
Lay down a layer of bone
Eventually become osteocytes
Activity increased by stress
Osteoclasts
Bone re-absorbing cells
Eat away at old bone
Activity increased by absence of stress (no gravity)

22. D. Bone Formation and Growth
Ossification begins in the diaphysis first and then in the epiphysis, eventually meeting

23. D. Bone Formation and Growth
Epiphyseal Plate (growth plate)
Cartilage between diaphysis and epiphysis ossification sites
As long as plate exists, growth is possible
When plate becomes calcified, an epiphyseal line is formed and growth is no longer possible

25. Bones of the Skeletal System
Two divisions of the skeleton
Axial Skeleton
Appendicular Skeleton
206 bones within the body
Important terms to know:
Process – projection or outgrowth from a larger body
Foramen – any opening

26. IV. The Axial Skeleton The Skull Cranium (8) Facial (14) Ear (6)
Sinuses

27. 1. Cranium (8) Bones that encase the brain Includes: Frontal (1)
Parietal (2)
Temporal (2)
Occipital (1)
Sphenoid (1)
Ethmoid (1)

28. Frontal (1)
Forehead bone

29. Parietal (2)
Side and top of cranium

30. Parietal (2)
Side and top of cranium

31. Temporal (2)
Lower sides

32. Temporal (2) Lower sides Includes: External auditory canal Mastoid
process
Styloid process

33. Occipital (1)
Back of skull

34. Occipital (1) Back of skull Contains the Foramen magnum - The hole the
spinal cord
enters the
cranium

35. Sphenoid Bat-shaped central part of cranium floor
Contains the pituitary gland

36. Sphenoid Bat-shaped central part of cranium floor
Contains the pituitary gland

37. Ethmoid (1)
Forms floor of cranium, side walls and roof of nose
Anterior to sphenoid

38. Ethmoid (1)

39. 1. Cranium Sutures Fontanels Immovable joints
Parietal bones form joints with other bones
Fontanels
Areas of the skull where ossification has not yet occurred
Become sutures by age 2

40. 2. Facial Bones (14) Includes: Nasal (2) Maxilla (2) Zygomatic (2)
Mandible (1)
Lacrimal (2)
Palatine (2)
Inferior concha (2)
Vomer (1)

41. Nasal (2)
Forms upper part of bridge of nose

42. Maxilla (2)
Upper jaw bone
Forms roof of mouth and floor of nose
Part of eye orbit

43. Zygomatic (2)
Cheek bones
Part of eye orbit

44. Mandible (1)
Lower jaw bone
Strongest facial bone

45. Lacrimal (2)
Forms medial wall of orbit and nasal cavity
Smallest facial bones
Tear ducts

46. Palatine (2)
Forms posterior roof of mouth

47. Inferior Concha (2)
In lateral nasal cavity

48. Vomer (1)
Posterior portion of nasal septum

49. 3. Ear (6) Malleus (2) Incus (2) Stapes (2) “hammer”
Attaches to eardrum
Incus (2)
“anvil”
Stapes (2)
“stirrup”

50. 4. Sinuses
Sinus – a space or cavity inside some cranial and facial bones
Mastoid Sinuses
Mucosa-lined spaces in mastoid process
Mastoiditis
Inflammation of sinuses
Infectious material cannot drain
May damage bone and spread to brain

51. 4. Sinuses Paranasal sinuses
Four pairs of sinuses that open into the nose
Frontal sinuses
Maxillary sinuses
Sphenoid sinuses
Ethmoid sinuses
Can become inflamed and infected causing pain

52. Paranasal sinuses

53. VII. Axial Skeleton
Spine (26)
33 vertebrae at birth, but 26 as adult

54. B. Spine Basic structure of the vertebrae Body Anterior, disk shaped
Vertebral foramen
Hole for spinal cord
Spinous process
Posterior projection
Transverse process (2)
Lateral projections
Articular process (4)
2 inferior and 2 superior
Permit limited and controlled movement between adjacent vertebrae

55. B. Spine Vertebrae Sections:
Classified into sections based on characteristics
Each vertebra is named by section’s first letter and vertebra’s place in order
Sections:
Cervical vertebrae
Thoracic vertebrae
Lumbar vertebrae
Sacrum
Coccyx

56. Cervical Verterbrae (7) [C1-C7]
Vertebrae of the neck
C1 – Atlas
Supports the skull
Has no body
C2 – Axis
Has a process called the dens, around which the atlas rotates

57. Cervical Verterbrae (7) [C1-C7]
Vertebrae of the neck
C1 – Atlas
Supports the skull
Has no body
C2 – Axis
Has a process called the dens, around which the atlas rotates

58. Thoracic Vertebrae (12) [T1-T12]
Vertebrae of the chest
All 12 ribs attach to this section

59. Thoracic Vertebrae (12) [T1-T12]

60. Lumbar Vertebrae (5) [L1-L5]
Vertebrae of the lower back
Thickest bodies
Largest and strongest
Supports body weight

61. Lumbar Vertebrae (5) [L1-L5]

62. Sacrum (1) Fusion of 5 vertebrae into one occurs in adulthood
Located between two coxal (hip) bones to form pelvis

63. Coccyx (1)
4 vertebrae fused into one

64. B. Spine Vertebral curvatures Give strength to support body weight
Provide balance to stand and walk
Babies have a continuous convex curve

65. B. Spine Abnormal vertebral curvatures Lordosis (A) Kyphosis (B)
Abnormal lumbar curve
“Swayback”
Kyphosis (B)
Abnormal thoracic curvature
“hunchback”
Scoliosis (C)
Abnormal side to side curvature

66. VII. Axial Skeleton
Thorax (25)
Sternum (1)
Ribs (24)

67. Sternum (1)
Breast bone

68. Ribs (24) All ribs attach to the thoracic vertebrae True Ribs (14)
Directly attach to the sternum by costal cartilage
True Ribs
(first seven pairs)

69. Ribs (24) False Ribs Do not directly attach to the sternum
8th, 9th, 10th rib attach to 7th’s costal cartilage
11th and 12th have no anterior attachment
“floating ribs”

70. VII. Axial Skeleton Hyoid bone U- shaped bone
Does not articulate with any other bone
Supports the tongue

71. VIII. Appendicular Skeleton
Bones of the Upper Extremity (64)
Clavicle (2)
Scapula (2)
Humerus (2)
Radius (2)
Ulna (2)
Carpals (16)
Metacarpals (10)
Phalanges (28)
Pectoral girdle

72. Clavicle (2)
Collar bone
Connects to sternum and scapula
Scapula (2)
Shoulder blade
Lies over posterior ribs

73. Humerus (2)
Upper arm bone
Connects to scapula
Radius (2)
Lateral forearm bone (thumb side)
Ulna (2)
Medial forearm bone (pinky side)

74. Carpals (16)
Bones of the wrist
Small bones for greater mobility
Metacarpals (28)
Bones of the palm of the hand
Phalanges (28)
Bones of the fingers
2 in thumb, 3 in fingers

75. VIII. Appendicular Skeleton
Bones of the Lower Extremity (62)
Coxal bone (2)
Femur (2)
Patella (2)
Tibia (2)
Fibula (2)
Tarsals (14)
Metatarsals (10)
Phalanges (28)

76. Coxal bone (2)
Pelvic girdle
Allows attachment of lower extremities to the axial skeleton
Ilium
Superior
Ischium
Inferior and posterior
Pubis
Inferior and anterior
Acetabulum
Deep, cup-shaped socket

77. Femur (2)
Thigh bone
Longest bone
Connects to coxal bone

78. Patella (2)
Knee cap
Floats in knee tendon

79. Tibia (2)
Shin bone
Medial lower leg bone
Fibula (2)
Lateral leg bone

80. Tarsals (14)
Bones of ankle and posterior foot
Calcaneus
Heel bone
Metatarsals (10)
Bones of the foot
Phalanges (28)
Bones of the toes
2 in 1st toe and 3 in the others

81. IX. Joints (Articulations)
There are three types of joints
Synathroses
Amphiarthroses
Diarthroses

82. A. Synarthroses No movement
Connective tissue grows between bones holding them close together
Ex: sutures of the skull bones

83. B. Amphiarthroses Slight movement Cartilage connects bones
Ex: the joint between the two pubic bones

84. C. Diarthroses Most joints are diarthrotic joints
Bones held together by ligaments
Synovial membrane surrounds the joint and secretes synovial fluid that lubricates the joint
Several types (you need to know 3)

85. C. Diarthroses Hinge Joint Allows movement in two directions
Elbow, knee, fingers

86. C. Diarthroses Ball-and-Socket Joint Allows the greatest movement
Shoulder and hip

87. C. Diarthroses Gliding Joint Flat surfaces “glide” over each other
Some carpals, vertebrae

88. X. Skeletal Disorders Osteoporosis
Definition: a disorder in which a loss of calcified bone occurs
Signs & Symptoms:
Bone porosity – lower bone density
Brittle and easily broken bones
Kyphosis
Etiology:
Metabolic bone disease
Affects post-menopausal women the most
Sex hormones stimulate bone production

89. Osteoporotic spongy bone
X. Skeletal Disorders
Osteoporosis
Treatments:
Drug/hormone therapy, exercise, calcium and vitamin D supplements
Osteoporotic spongy bone
Normal spongy bone

90. X. Skeletal Disorders Osteomyelitis Def’n: bone or marrow infection
Signs & Symptoms:
Persistent/severe pain, muscle spasms, swelling, fever
Could lead to necrosis of the tissue
Etiology
Infectious mechanism
Treatment: Antibiotics, possibly amputation

91. X. Skeletal Disorders Bone Fractures
Def’n: increased stress resulting in bone breaks or fractures
Usually traumatic mechanism, sometimes metabolic or neoplastic
After a fracture, a callus is formed to stabilize the area for new bone growth

93. X. Skeletal Disorders Bone Fractures Types:
Open or Compound Fractures - Fracture where bone pierces the skin
Closed or Simple Fractures - Fractures where the bones do not pierce the skin
Complete – bone fragments separate completely
Incomplete – bone fragments partially separate
Sometimes called “greenstick” fractures
Comminuted – breaks that produce many fragments
Impacted fractures – bone fragments are driven into each other

95. X. Skeletal Disorders Joint Disorders Noninflammatory joint disease
No inflammation of the synovial membrane
Osteoarthritis (Degenerative Joint Disease, DJD)
Degeneration of articular cartilage
Idiopathic; risk factors – age and joint damage
Traumatic Injury
Dislocation – displacement of a bone
Sprain – injury to ligaments around a joint
Strain – injury to muscles or tendons attached to a bone

96. X. Skeletal Disorders Joint Disorders
Inflammatory Joint Disease (Arthritis)
Inflammation of the synovial membrane
Rheumatoid arthritis
Autoimmune disease
Chronic inflammation of membrane that spreads to other tissues
Gouty arthritis
Uric acid increases in the blood and deposits as crystals in joints
Causes inflammation and joint damage

97. THE END!!!