1. Chapter 6
Skeletal System

3. Skeletal System Functions
Support/framework
Protect
Movement and anchorage
Mineral storage
Hemapoiesis (formation of RBC)

4. Functions (red and white blood cells)
Framework/Support: body structure and shape
Protection: for vital organs(brain, heart, etc.)
Levers/Movement for attached skeletal muscles wk with muscular sys for mvmt***
Tendons: attach muscle to bone
Ligaments: attach bone to bone
Mineral storage: calcium and phosphorus
Blood cell formation - hematopoiesis
(red and white blood cells)

5. Structure and Formation of Bone
Osteocytes
Mature bone cell
1. Organic material 35%
(flexibility)
Collagen, a fibrous material
Jellylike material is between the collagen
2. Inorganic material salts and water 65%
(hardness and durability)
- calcium phosphate, calcium carbonate, calcium fluoride, magnesium phosphate, sodium oxide & sodium chloride

6. Females grow until about 18 years of age
Growth
Females grow until about 18 years of age
Males grow until about years of age

7. Osteoblasts: bone building, bone repairing cells in the periosteum
Composition
Cells
Osteoblasts: bone building, bone repairing cells in the periosteum
Osteocytes: mature bone cells within the bone
Osteoclast: causes reabsorption of bone

8. Cells that Aid in Bone Formation
Osteoblast
Builds new bone tissue
Mature bone cell
Osteocyte
OsteoblastsOsteoblasts are responsible for building new bone and lie at the centre of bone physiology. Their functions include the synthesis of collagen and the control of mineralisation.
OsteoclastsOsteoclasts are specialised cells that resorb bone. They work by sealing off an area of bone surface then, when activated, they pump out hydrogen ions to produce a very acid environment, which dissolves the hydroxyapatite.
OsteocytesBone adapts to applied forces by growing stronger in order to withstand them; it is known that exercise can help to improve bone strength. Osteocytes are thought to be part of the cellular feed-back mechanism which directs bone to form in the places where it is most needed. They lie within mineralised bone and it is thought that they may detect mechanical deformation and mediate the response of the osteoblasts.
Osteoclast
Eats bone 8

9. Bone Formation
Skeleton fully formed by 2nd month of fetal development (all cartilage)
After 8th week of fetal development ossification begins (mineral matter deposited and replaces cartilage)
Childhood and adolescence:
ossification exceeds bone loss
Early adulthood thru middle age:
ossification equals bone loss
After age 35:
bone loss exceed ossification***

10. 275 bones 12 weeks (6-9 inches long)
Fetal Skeleton
275 bones 12 weeks (6-9 inches long) 10

11. Types of Bone

12. Bone Types Long bones Flat bones Irregular bones Short bones
Sesamoid bones

13. Long bones Found in the extremities Act as levers
Examples: femur, tibia, fibula, humerus,
radius, clavicle, metacarpals, phalanges

14. Short Bones Cube shaped Allows flexible movement Examples: Carpals
Tarsals

15. Flat Bones
Protect vital organs and provide broad surface area for muscle attachment
Examples:
Cranial bones
Scapula
Sternum
Ribs

16. Irregular Bones
Peculiarly shaped to provide support and protection, yet allow flexibility
Examples:
Vertebrae
Mandible

17. Sesamoid Bones
Extra bones found in certain tendons
Example:
Patella

18. Classification of Bones

19. A. Long B. Short C. Irregular D. Sesamoid E. Flat3. 1. 4. 5. 2.

20. Anatomy of Long Bone Diaphysis (dye-AF-ih-sis)
Shaft
Composed of compact bone
Epiphysis (eh-PIF-ih-sis)
Ends of bone composed mostly
of spongy bone
Periosteum (pehr-ee-OSS-tee-um)
outside covering of diaphysis
Endosteum (en-DOS-tee-um)
Lines medullary cavity
Arteries
Articular cartilage
Medullary cavity (MED-you-lehr-ee)
Cavity inside the shaft
Contains yellow marrow (mostly fat) in adults

22. Structure and Formation of Long Bone
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23. Long Bones Shaft or diaphysis Each end is the epiphysis
Covered by articular cartilage
In the center is the medullary canal
Yellow bone marrow
Endosteum (lining of the marrow canal)

24. Long Bones Red marrow Periosteum Ends of long bones
Manufactures red blood cells and some white blood cells
Periosteum
Covering on the outside of the bone

25. Bone Marrow Red bone marrow Yellow bone marrow
Found in vertebrae, ribs, sternum, cranium, ends of humerus and femur
Produces:
Erythrocytes – red blood cells
Plateletes - thrombocytes – clotting cells
Some leukocytes – white blood cells
Yellow bone marrow
Found in medullary cavity of long bones
Fat storage

26. Bone Marrow Yellow marrow Medullary cavity of long bones Fat storage
Red marrow
Hematopoietic tissue
In all cancellous bone in children
In adults: cancellous bone of vertebrae, hips, sternum, ribs, cranial bones, proximal ends of femur and humerus
Forms RBCs, platelets, some WBCs, and destroys old RBCs and some foreign materials

27. Divisions of the Skeletal System

28. Appendicular skeleton
Skeletal System
Axial skeleton
Skull, spinal column, ribs, sternum, and hyoid bone
Appendicular skeleton
Upper and lower extremities

29. Spinal column (vertebra) Ribs and sternum
Axial Skeleton
22 bones of the skull
14 facial bones
Spinal column (vertebra)
Ribs and sternum

30. Axial Skeleton Forms the longitudinal axis of the body
Divided into three parts:
Skull
Vertebral Column
Thorax

31. DID YOU KNOW…
The giraffe, with its long neck, has the same number of cervical vertebra as a human…just much longer.

32. The Skull
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33. The Skull
© 2014 Cengage Learning.

34. Sutures- connects parietal bones to temporal bones

35. Fontanelle

36. Appendicular Skeleton
Composed of 126 bones
Includes bones of the:
Limbs (appendages)
Pectoral (shoulder) girdle
Pelvic (hip) girdle

37. Appendicular Skeleton - Upper Extremities
Shoulder girdle
Arm
Hand

38. Appendicular Skeleton - Lower Extremities
Pelvic girdle
Upper leg
Lower leg
Ankle
Foot

39. 1. Synarthroses (immovable) joints
Called articulations
Points of contact between two bones
1. Synarthroses (immovable) joints
2. Amphiarthroses (partially movable) joints
3. Diarthroses (movable) joints

40. Classification 1. Synarthrotic: immovable - cranium
Amphiarthrotic: limited movement
Ex. pubic symphysis, vertebral joints, sacroiliac joint
3. Diarthrotic: freely movable
Gliding: bones of the wrist
Pivot: between radius and ulna
Ball and socket: hip
Hinge: elbow

41. 1. Synarthroses Joints Immovable joints
Connected by tough, fibrous connective tissue
Example:
Adult cranium
Cranial joints are called sutures

42. 2. Amphiarthroses Joints
Partially movable joints
Cartilage between their articular surfaces
Examples:
Ribs to the spine
Symphysis pubis

43. 3. Diarthroses Joints Movable joints Ball-and-socket joints
Hinge joints
Pivot joints
Gliding joints

44. Types of Motion
Flexion
Extension
Abduction
Adduction
Rotation

45. Aging of the Bones and Joints
Bone mass and density decline
External surfaces of the bones thicken
Intervertebral cartilage disks shrink
Center of balance is altered
Joints less mobile
Increased rigidity and decreased flexibility
Fear of falling

46. Skeletal System Diseases and Disorders
Unit 6.3

47. Disorders of the Bones and Joints
Fracture
Greenstick
bent and split, incomplete break
Closed/simple
complete break of the bone with no damage to skin
Open/compound
bone breaks ruptures skin
Comminuted
Two or more bones that are broken into smaller pieces 

48. Disorders of the Bones and Joints
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49. Repairing Fractures Closed reduction Open reduction
Traction ( pulling forced used to get the bones in place) used for fx of long bones

50. Other Bone and Joint Injuries
Dislocation
bone is displaced from a joint
Sprain
twisting action tears ligaments
Hammer toe (toe that is curled or flexed)
RICE Treatment
Rest
Ice
Compression
Elevation

51. Diseases of the Bones Arthritis Gout Rickets Rheumatoid arthritis
Osteoarthritis
Gout
Rickets

52. Other Bone and Joint Injuries
Slipped (herniated) disc
Whiplash injury

53. Abnormal Curvatures of the Spine
Kyphosis (kye-FOH-sis) hunchback
Lordosis (lor-DOH-sis) swayback
Scoliosis
Side to side curvature
PAGE 109 in book

54. Other Disorders Osteoporosis (AKA: silent disease) Osteomyelitis
no symptoms until injury
Detrition of bone
Osteomyelitis
Inflammation/infection of the bone
Osteosarcoma
Bone cancer

55. Arthritis (tx ASA & exercise)
Two main types:
Rheumatoid
Osteo
*Gouty Arthritis ( 1st attack in the big toe)* too much uric acid

56. Rheumatoid
Chronic inflammatory disease affecting the connective tissues and joints
More common in women
Onset around age 35-45
Causes permanent deformity and immobility
Early treatment is key
Treatment: Rest, medications, steroids, surgery

59. Osteoarthritis Most common form Chronic result of aging
Symptoms: joint pain, stiffness, aching, limited range of motion,
No cure
Treatment: Rest, anti-inflammatory medication, , steroid injections, hot/cold applications, and exercises

61. Bursitis Inflammation of the bursae
Small fluid filled sacs around the joints
Symptoms: Severe pain, fluid accumulation
Treatment: pain meds, steroids rest, aspirating fluid, and physical therapy

63. Fracture-crack or break in bone
Green stick- bent and split, incomplete break
Simple/closed- complete break of the bone with no damage to skin
Compound/open- bone breaks ruptures skin
Impacted- broken ends jam into each other
Comminuted- bone splinters into more than two pieces.
Spiral- twist resulting in one or more breaks
Depressed-skull moves inward common in head injuries
Colles- breaking and dislocation of the radius (falling outstretched hand)

65. Reduction- proper alignment for healing
Closed reduction- cast or splint
Open reduction- surgical repair
Dislocation- bone is displaced from a joint
Sprain- twisting action tears ligamnets

66. Osteomyelitis Bone infection and inflammation
Symptoms: severe pain, fever chills, swelling
Treatment: IV antibiotics

69. Osteoporosis Metabolic disorder caused by hormone deficiency
Loss of calcium and phosphorus causes
Bone density test
Treatment: increased intake of Vitamin D, medications to increase bone mass, exercise and estrogen replacement

72. Ruptured Disk (Herniated or ruptured disk)
Padding between disk ruptures or protrudes out
Symptoms: pain, muscle spasm, immobility
Treatment: rest, traction Physical therapy or massage

75. Compound Fracture
bone “breaks” or tears through skin – very serious, infection can occur

77. Comminuted Fracture
bone breaks into pieces – common in elderly, bones are more brittle

78. Compression Fracture
bone is compressed or crushed
common in vertebra – common in older people due to osteoporosis

79. Depressed Fracture
bone is pressed inward – common in skull fracture

80. Impacted Fracture
bone ends are forced into each other – common when attempting “break your fall” with outstretched arms

81. Spiral Fracture
results from excessive twisting force

82. Greenstick Fracture
incomplete break (like a green twig) common in children due to more flexibility in bones than adults

83. BONE REPAIR
Callus
zone of tissue repair
Several Steps
1. blood clot forms
days later, cells enter and produce fibers which hold bones together
cartilage is then produced
3. osteoblasts enter the callus and form spongy bone – takes 4-6 weeks
4. spongy bone is remodeled into compact bone
this healing can take up to a year

84. Scoliosis
abnormal lateral curvature of the spine

85. dislocation
violent disruption of the integrity of a joint – many different types

88. Rickets
caused by vitamin D deficiency (can be from lack of sunlight)