1. Includes bones, cartilage, and joints
The SKELETAL System
Includes bones, cartilage, and joints

2. Functions of the Skeletal System
Support
Protection
Movement Facilitation
Mineral Storage and Homeostasis
Storage of energy
Hematopoiesis

3. Types of Bone Cells Osteogenic Cells = bone stem cells
Osteoblasts = deposit Ca+ & P & collagen fibers--bone builders
Osteocytes = mature bone cells-maintain tissue
Osteoclasts = break down bone tissue

4. Osteoblasts and Osteoclasts

5. Bone Growth aka Ossification
The process by which bones form in the body (Osteogenesis)
Replacement of pre-existing connective tissue with bone

6. Intramembranous Ossification
Membranes ----> Bone
Periosteum - Width-wise Growth
Examples: skull bones, mandible, clavicle

7. Endochondral Ossification
Cartilage ----> Bone
Epiphyseal (growth) Plate –
Length-wise growth
Examples: most of skeleton

8. Bone Structure Periosteum – outside membrane
--Fibrous Layer-protection
--Osteogenic Layer-stem cells
Diaphysis = shaft of a long bone
Epiphysis = ends of long bones

9. Bone Structure Medullary Cavity or Canal
Yellow Marrow-in cavity--fat storage
Red marrow--blood cell forming tissue
Endosteum-lines medullary canal
Articular (joint) Cartilage - Hyaline Cartilage

10. Compact Bone Structure (densely packed – strength)
Dense & organized
Lamellae: layers of bone
Circular or interstitial
Osteons (Haversian canals)--contains vertical canals - blood vessels and circular lamellae with lacunae

11. Compact bone structure
Perforating or Volkman’s Canals - horizontal canals with blood vessels
Lacunae: spaces that hold osteocytes
Canaliculi: minute canals where osteocytes stretch out
FYI: connect to other lacunae and eventually with central or perforating canals
Gives bone strength

12. Spongy bone (loosely packed-reduces weight
AKA -Trabecular Bone
Irregular network
Thin plates of bone with lots of intercellular space
Spaces filled with Red Bone Marrow
Responsible for Hematopoiesis

13. Types of Bones
Long Bones: Longer than wide, have a shaft, slightly curved –spongy bone on ends. Examples: humerus, ulna, tibia, metacarpals, phalanges
Short Bones: cube shaped, near equal in length and width, spongy bone on inside. Examples: carpals and tarsals
Flat Bones: thin and flat, compact bone outside & spongy bone inside, provide protection. Examples: cranial bones, ribs, sternum, scapula

14. Types of Bones (cont.) Irregular – odd shaped
Vertebrae
Sesmoid – encased in tendon
Patella
Ball of foot

15. Bone Markings
Foramen= a hole for blood vessels, nerves, or ligaments

16. Bone Markings
Meatus= canal or passageway through bone

17. Sinuses Sinus= cavity or space in a bone, lightens the skull
Frontal - forehead
Sphenoid - back of nose
Ethmoid – sides of nose
Maxillary – upper jaw

18. Fossa A fairly deep pit or depression
Examples include the olecranon fossa of the humerus and the mandibular fossa of the temporal bone

19. Bone Markings
Process = any projection from the surface of a bone. Example: spinous processes
Condyle = “Knuckle” - a large rounded prominence on a bone. Found on femur

20. Bone Markings cont
Trochanter = a large blunt process found only on the femur
Tubercle = a small rounded process

21. Bone Markings cont
Tuberosity = an elevated, rounded, usually roughened area of a bone
Facet = a smooth articular surface

22. Bone Markings
Head= proximal end of bone, rounded projection

23. Medial and Lateral Malleolus
Medial malleolus on the tibia
Lateral malleolus on the fibula
Make the ankle bones

24. Sutures Immovable joints Sagittal: separates parietal bones
Coronal: separates frontal from parietal
Lambdoid: separates occipital from parietal
Squamous: separates temporal from parietal

25. Fontanels Provide room for rapid brain growth Make childbirth easier
Move during childbirth
Used for access to blood sampling and IV’s

26. Axial vs. Appendicular Axis of the body Three regions Appendages
Skull
Vertebral column
Bony thorax
Appendages
Connected to trunk
Shoulder girdle
Pelvic girdle
Upper limbs
Lower limbs

27. Axial Skeleton Axis of the body--through the midline Three regions
Skull
Vertebral column
Bony thorax

28. Skull Cranial Bones: six external bones and two internal bones
Facial Bones: 14 Facial bones

29. Major Skull Bones Cranial Frontal Parietal Occipital Sphenoid Ethmoid
Temporal
(Mastoid Process)
Facial
Zygomatic Mandible
Nasal Maxilla

30. Frontal Bone
Forms the forehead
Forms the roof of the eye sockets

31. Parietal bone Consists of two bones
Forms the sides and roof of the cranial cavity

32. Occipital Bone The base of the cranial cavity
Prominent posterior portion –occipital protuberance

33. Sphenoid Temple bone Makes up part of cranial floor
Makes up part of orbit
Looks like butterfly/bat

34. Ethmoid Separates the nasal cavity from the brain
Roof of the nose, between the two orbits
Helps to make up the orbit of the eye

35. Temporal Bones Consists of two bones Forms the lower sides of the
Mastoid process
Consists of two bones
Forms the lower sides of the
cranium and part of the cranial floor

36. Zygomatic
Cheek bones

37. Nasal
Bridge of the nose

38. Mandible
The Lower Jaw

39. Maxilla
The Upper Jaw

40. Vertebral Column Vertebrae can be identified by three criteria:
1. Shape and angle of the spinous process
2. Size of the vertebral body
3. Presence or absence of transverse foramen

41. Vertebral Column Divided into five regions Cervical - neck
Thoracic - chest
Lumbar – low back
Sacrum - hips
Coccyx - tailbone

42. Intervertebral Disks Made of fibrocartilage
Provide cushioning and shock absorption for vertebrae

43. Hyoid Bone Does not articulate with any other bones
Tongue muscles attach here
Aids in swallowing

44. Bony Thorax Sternum--Manubrium, body, and xiphoid process
12 pair of ribs
7 pair of true ribs
3 pair of false ribs
2 pair of floating ribs

45. Appendicular Skeleton
Attached to Axial
Pectoral Girdle
Pelvic Girdle
Upper and Lower Extremities

46. The Pectoral Girdle
Attaches the bones of the upper extremities to the axial skeleton
Clavicle & scapula

47. Upper extremities Humerus – upper arm Radius – thumb side forearm bone
Ulna – pinky side forearm bone
Carpals – wrist
Metacarpals – hand
Phalanges - fingers

48. The Pelvic Girdle (Hip girdle)
Attaches the bones of the lower extremities to the axial skeleton
Pelvic or coxal bone

49. Female Vs. Male Pelvis Light and thin Wide ilium
Pubic arch greater than 90o
Wide sciatic notch
Pelvic outlet wide
Coccyx more moveable
Heavy and thick
Narrow ilium
Pubic arch less than 90o
Narrow sciatic notch
Narrow pelvic outlet
Coccyx less moveable and less curved

50. Lower Extremities Os coxa- pelvis Femur – thigh Patella – kneecap
Ilium
Ischium
Pubis
Femur – thigh
Patella – kneecap
Tibia – shin
Fibula – outer lower leg
Tarsals - ankle
Metatarsals - foot
Phalanges - toes

51. Names for thumb and big toe
Thumb: Pollex
Big toe: Hallux

52. JOINTS

53. Fibrous Joints Immovable Thin layer of fibrous connective tissue
Sutures (skull)
Gomphosis (teeth)

54. Cartilaginous Joints Bones connected by cartilage Slightly moveable
Pubic Symphysis
Intervertebral joints

55. Synovial Joints Contain synovial cavity Ligaments Freely moveable
Several different kinds based on degree of motion

56. Types of Synovial Joints
Saddle / Ball and Socket
Gliding /Hinge
Pivot / Condyloid

57. Supporting structures in synovial joints
Bursa: small sack filled with synovial fluid
Meniscus: Pad of cartilage in the knee joint
Ligaments: connect bone to bone

58. Diseases and Disorders of the Skeletal System

59. Herniated Discs(Slipped Discs)
rupture of fibrocartilage discs
caused by compression forces
occurs between L4 & L5 or L5 & 1st Sacral Vertebrae
disc protrudes and exerts pressure on spinal nerves

60. Osteoarthritis Degenerative joint disease associated with aging
Characteristics:
degeneration of articular cartilage
development of bone spurs
usually effects large joints (knees, hips, etc)

62. Osteoporosis Decrease in bone mass
Increase in susceptibility to fractures

63. Abnormal Curvatures of the Spine
Scoliosis = lateral curvature of the spine

65. Abnormal Curvatures of the Spine
Kyphosis = hunchback/humpback
exaggeration of thoracic curvature 65

67. Abnormal Curvatures of the Spine
Lordosis = swayback
exaggeration of lumbar curvature 67

68. Spina Bifida congenital defect usually involves the lumbar vertebrae
Symptoms mild to severe
can be diagnosed during pregnancy by sonography, amniocentesis, blood tests

69. INFANTS WITH SPINA BIFIDA

70. Classification of Bone Fractures
Closed (Simple) Fracture = bone does not break through skin
Open (Compound) Fracture = bone ends break through skin
Partial (Incomplete) Fracture = break does not completely transect bone (Greenstick Fracture)
Complete Fracture = break transects bone & divides into two or more pieces

71. Bone Fractures
Closed Reduction = re-alignment without surgical intervention
Open Reduction = re-alignment by surgical procedures 71

72. COMMON BONE FRACTURES

73. FYI: Classification of Bone Fractures
Pott’s Fracture = fracture distal end of Fibula
Colles’ Fracture = fracture of distal end of radius
Stress Fracture = fracture due repeated stress
usually caused by:
training habits(Volume-Intensity-Duration)
change in training surface
25% involve distal third of fibula

74. Sprains Forcible wrenching or twisting of a joint
1st Degree Sprain = stretching of ligaments
2nd Degree Sprain = partial tearing of ligaments
3rd Degree Sprain = complete tear of ligaments

75. THE END