1. Why study bones?

2. SKELETAL SYSTEM PHYSIOLOGY
CHAPTER 7 CONT…

3. Overview of Skeletal System
Bones
Joints
Cartilage
Ligaments (bone to bone)
Tendons (bone to muscle)

4. Bones are alive!!!! Bones consist of: Functions of bone:
Bone tissue, cartilage, dense connective tissue, blood, and nervous tissue
Functions of bone:
Points of attachment
Protect and support
House blood producing cells
Store inorganic salts
Form passageways for blood vessels and nerves

5. Bone Classification Bones are classified according to their shape.
Long bone
Long longitudinal axes and expanded ends
Ex. Femur, ulna
Short bone
Cube like, lengths and widths roughly equal
Carpals, tarsals
Flat bone
Plate-like with broad surfaces
Scapula, skull bones

6. Irregular bone Sesamoid (round) bone
Variety of shapes, usually connected to other bones
Vertebrae, hip
Sesamoid (round) bone
Small, nodular
patella

8. Types of Bone Tissue Compact Bone: Hard outer layer of bone
Spongy bone: Less dense, small needle-like pieces of bone (trabeculae) with many open spaces
Bone marrow: Soft tissue inside bone that produces blood cells

9. Parts of a long bone Epiphysis: articulates with other bones
Spongy bone: numerous branching
plates
Articular cartilage: hyaline cartilage
Diaphysis: shaft of bone
Medullary cavity: hollow chamber
filled with yellow marrow
Endosteum: lines medullary cavity
Periosteum: tough vascular covering
that encloses bone
Compact bone: tightly packed tissue
in diaphysis

10. Parts of a Long Bone Diaphysis Shaft Composed of compact bone
Location of yellow marrow (yellow b/c mostly fat)
Epiphysis
Ends of the bone
Composed mostly of spongy bone
Location of red marrow (blood formation)

11. Parts of a Long Bone Periosteum Arteries
Outside covering of the diaphysis
Fibrous connective tissue membrane
Arteries
Supply bone cells with nutrients

12. Parts of a Long Bone Articular cartilage
Covers the external surface of the epiphyses
Made of hyaline cartilage
Decreases friction at joint surfaces
Medullary cavity
Cavity of the shaft
Contains yellow marrow (mostly fat) in adults
In children, red marrow is also found here (for blood cell formation)

13. Blood cell formation Hematopoiesis (process of blood cell formation)
Begins in the yolk sac (before birth outside embryo)
Manufactured in liver & spleen (after birth)
Form in bone marrow (later in development)
Bone Marrow
Soft, netlike mass of connective tissue
Red marrow: forms erythrocytes (RBC), leukocytes (WBC), thrombocytes (platelets)
Hemoglobin (carries O2) gives it its red color
Yellow marrow: stores fat
eventually replaces red marrow as you age

15. Parts of Bone Terminology (p.142)
A bones shape makes possible its function.
Processes: bony projections on bones provide sites for ligaments and tendons to attach.
Ligaments connect bone to bone
Tendons connect bone to muscle
Grooves/Openings: provide
passageways for blood
vessels/nerves

16. Fissure: a groove or deep furrow in the bones or various parts of the body.
Sinus: cavity in bone of skull filled with air in the bones of the face and skull
They lighten the weight of the skull and this is the reason why your head feels heavy and you feel tired and sleepy during a sinus attack.
They give resonance to your voice.
They also filter and moisten the air that we breathe.
They also remove unwanted air particles.

17. Fontanels “soft spots” on an infant’s skull; membranes that cover space between bones

18. Sutures – interlocking line of union between bones (ex
Sutures – interlocking line of union between bones (ex. Sutures of the skull)

19. Foramen - refers to any opening in the skull, nerves and blood vessels leave this opening to supply the face
Foramen Magnum
Hole in the base of the skull through which
the spinal cord passes
Mental Foramen

20. VERTEBRAL COLUMN p.147-151 Cervical - 7 Thoracic – 12 Lumbar - 5
Spinous process
Lamina
Vertebral foramen
Body

21. VERTEBRAE COLUMN p
Typical vertebra have a drum-shaped body that support the weight of the head and trunk
Intervertebral discs that separate adjacent vertebral bodies, cushion and soften forces of movements like walking and jumping
The pedicles, laminae, and spinous process together form a bony vertebral arch around the vertebral foramen, through which the spinal cord passes

22. VERTEBRAE p
The first 2 cervical vertebrate are special…they have no body
1.) atlas - nod head yes
2.) axis - pivot head (side to side)

23. Ossification: Bone Growth
Bones form by replacing existing connective tissue in either of 2 ways:
1. Intramembranous bones broad, flat bones of the skull that form membrane-like tissue into osteoblasts
2. Endochondral bones begin as masses of cartilage that are later replaced by bone tissue (most bones)
Ossification:
formation of bone

24. Types of Bone Cells Osteocytes Osteoblasts Osteoclasts
Mature bone cells
Osteoblasts
Bone-forming cells for bone growth
Osteoclasts
Bone-destroying cells
Break down bone matrix for remodeling and release of calcium
Bone remodeling is a process done by both osteoblasts and osteoclasts

25. Endochondral Bones
Epiphyseal plate: band of cartilage between the epiphysis and diaphysis. Includes layers of young cells undergoing mitosis and producing new cells. As these cells enlarge, this plate thickens, lengthening the bone.

27. Differences Male and Female Skeleton (p. 159)
BODY PART
FEMALE
MALE
SKULL
Smaller/lighter, rounder, chin more pointed, less pronounced brow ridges, smaller projections behind ears (mastoid process)
Larger/heavier, square chin, larger brow ridges, larger projections behind ears (mastoid process)
PELVIC GIRDLE
Lighter, thinner
Heavier, thicker
PELVIC CAVITY
Wider, shorter, & roomier/less funnel shaped
SACRUM
Wider
COCCYX
More movable

29. Gender Differences of the Pelvis
Male:
Not as wide or broad
Pelvic cavity is funnel-shaped
Bones are heavier & larger
Pubic arch more narrow
Female:
Wider pelvis & broader hips
Pelvic cavity is shallow
Bones are lighter & thinner
Pubic arch is wider

30. BONE FRACTURES pg. 136 A break in a bone Types of bone fractures
Closed (simple) fracture – break that does not penetrate the skin
Open (compound) fracture – broken bone penetrates through the skin
Bone fractures are treated by reduction and immobilization
Realignment of the bone

31. Common Types of Fractures

32. REPAIR OF BONE FRACTURES (pg. 136)
Major steps for fracture repair
1. blood escapes from ruptured blood vessels and forms a hematoma.
2. Spongy bone forms in regions close to developing blood vessels, and fibrocartilage forms in more distant regions.
3. A bony callus replaces fibrocartilage.
4. Osteoclasts remove excess bony tissue, restoring new bone structure much like the original.

33. Repair of Bone Fractures

34. How Does a Bone Heel ???

35. JOINTS Joints & Movements Degree of Movement: Synarthrotic – immovable
Amphiarthrotic – slightly moveable
Diarthrotic – freely moveable

36. Joints (articulations)-the body has 230
Functional junctions between bones
Type of tissue that binds the bone:
1. Fibrous joints
Generally immovable
Fibrous connective tissue join bone to bone
Ex. Cranial bones
2. Cartilaginous joints
Immovable or slightly moveable
Fibrocartilage found between bones
Ex. Vertebrae, ribs/sternum, pelvis

37. 6 Types of Synovial Joints classified by shape and movement (pg.165)
Freely moveable joints
Most joints are synovial
Bones do not come in contact with each other
Some have menisci (shock absorbing pads), others have bursae (fluid filled sacs)
6 Types of Synovial Joints classified by shape and movement (pg.165)
1. Ball and socket
2. Condyloid
3. Gliding
4. Hinge
5. Pivot
6. Saddle

38. 6 Types of Synovial Joints
Ball and socket – movement in all planes, rotation (shoulder, hip)
Condyloid – variety of movements in different planes, no rotation (metacarpals, phalanges)
Gliding – sliding/twisting movements (wrist, ankle)
Hinge – movement in one plane only, flexion/extension (elbow, phalanges)
Pivot – rotation around central axis (radius, ulna)
Saddle – variety of movements mainly in two planes
(thumb)

40. Body Movements
Bones and muscles interact as levers.

41. Types of Joint Movements p. 165-167
flexion supination
extension eversion
dorsiflexion inversion
plantar flexion retraction
hyperextension protraction
abduction elevation
adduction depression
rotation
circumduction
pronation

43. BONE PROBLEMS Bone cancer Abnormally active osteoclasts destroy bone
Bone marrow transplant - needle/syringe removes RBM from a healthy donor and injects into bloodstream of patient
Use stem cells from umbilical cord of newborn as well
Treats blood disorders/SCA/Leukemia

44. Cleft Palate
Fusion of palatine process of the maxilla is incomplete at birth

45. Spina Bifida Hip fracture
Laminae of vertebrae fails to unite,
vertebral arch remains incomplete.
Lumbar region is usually affected.
Hip fracture
Usually in elderly people, occurs in neck of femur b/w trochanters

46. Ruptured/Herniated Disk
Intervertebral disks are made of tough, outer layer of fibrocartilage and an elastic central mass. Over time. The disk degenerates or ruptures and can press on spinal cord causing back pain and numbness.
Osteoporosis
loss of bone volume and mineral content; spaces fill with fatty tissue; can cause spontaneous fractures; occurs mainly in white females past menopause
Arthritis
Inflamed swollen and painful joints; causes restricted movements; articular cartilage is damaged
Ex. Rhematoid arthritis (severe)

47. Disorders of the Skeletal System
Osteoporosis
Most common bone disease
1 in 5 women in USA over 50
have osteoporosis
Men over 70 are at risk
During menopause, estrogen levels drop
Body stops making new bone due to lack of calcium, resulting in brittle bones and fractures

48. Osteoporosis

49. Arthritis Inflammation of one or more joints
Breakdown of cartilage causes bones to rub together, leading to pain, inflammation, and stiffness
There are many different types of arthritis

50. Arthritis Osteoarthritis (OA) Most common type of arthritis
Caused by ‘wear and tear’ on joint
Cartilage breaks down and bony spurs may develop
Runs in families

51. Arthritis Rheumatoid arthritis (RA) Autoimmune disease
Body mistakenly attacks healthy tissues, breaking down cartilage
Common in middle aged people
Women get RA more than men

52. Arthritis
Gout
Type of arthritis that occurs when uric acid builds up in the blood, causing crystals to form in the joint
Leads to major inflammation
More common in men, women after menopause, and those who drink alcohol