The Skeletal System Chapter 5 1

Objectives: •List and describe the major functions of the skeletal system. •Describe the types of various bone tissues, their locations, and functions. •List, describe and give specific examples of the types of bones. •List and describe the two major divisions of the skeletal system and the bones which compose each. •Describe the process of bone formation. •List and describe the various types of joints. •List and describe various disorders and diseases of the skeletal system. 2

The Skeletal System What would you look like if you did not have any bones? Take a minute a make a sketch of what you think you might look like. Could you stand up? Could you walk? Without bones you would be just a puddle of skin and organs on the floor. Click on the trunk's lid and then use the red knob to pull the object from the trunk.

The human skeleton contains 206 bones!

Functions of the Skeletal System •Support of the body •Protection of soft organs •Movement due to attached skeletal muscles •Storage of minerals and fats •Blood cell formation (hematopoiesis) 3

Where marrow is located Types of Bone Tissue ·The skeleton has 206 bones ·Two basic types of bone tissue ·Compact bone ·Homogeneous ·Located on the outside surface ·Spongy bone ·Small needle-like ·pieces of bone (trabeculae) ·Many open spaces Where marrow is located Diagram on p. 118 4

Compact Bone Spongy Bone - hard bone - surrounds spongy bone - made of osteon systems that contain blood vessels - made of osteocytes (living bone cells) - less dense bone - contains many holes and spaces spongy compact

Classification of Bones by Shape •Long bones –Typically longer than wide –Have a shaft (long, central cylinder) with heads at both ends –Contain mostly compact bone •Examples: Femur, humerus •Short bones –Generally cube-shape –Contain mostly spongy bone •Examples: Carpals, tarsals 5

Classification of Bones by Shape •Flat bones –Thin and flattened –Usually curved –Thin layers of compact bone around a layer of spongy bone •Examples: Skull, ribs, sternum •Irregular bones –Irregular shape –Usually with projections (processes) or openings (foramen) –Do not fit into other bone classification categories •Example: Vertebrae and pelvic bones 6

Classification of Bones by Shape Diagram on p. 117 7

Color in the types of bones based on the correct classifications.

Microscopic Bone Anatomy Diagram on p. 120 8

Microscopic Bone Anatomy •Osteon (Haversian System) –A unit of bone •Central (Haversian) canal –Opening in the center of an osteon –Carries blood vessels and nerves •Perforating (Volkman’s) canal –Canal perpendicular to the central canal Diagram on p. 120 9

Microscopic Bone Anatomy •Lacunae –Cavities containing bone cells (osteocytes) –Arranged in concentric rings •Lamellae –Rings around the central canal –Sites of lacunae •Canaliculi –Tiny canals –Radiate from the central canal to lacunae –Form a transport system between cells Diagram on p. 120 10

Bone Cell Types •Osteocytes •Osteoblasts •Osteoclasts –Mature bone cells surrounded by matrix •Osteoblasts –Bone-forming cells produce new matrix •Osteoclasts –Bone-destroying cells –Break down bone matrix for remodeling and release of calcium •Bone remodeling is a process by both osteoblasts and osteoclasts. –During your life span the your skeleton is broken down and rebuilt completely on the average of seven times! 11

Canaliculi Lamella Sharpey's fibers Lacunae Osteocytes Haversian/central canal Blood vessel Periosteum Lamella Osteon Volkmann's canal Compact bone Spongy bone

Review! Bone Classifications Long Bones Flat Bones Irregular Bones Short Bones

Gross Anatomy of a Long Bone Diagram on p. 118 •Diaphysis –Shaft –Composed of compact bone •Epiphysis –Ends of the bone –Composed mostly of spongy bone –Contains red marrow •Medullary cavity –Cavity of the shaft –Contains yellow marrow (mostly fat) in adults •Articular cartilage –Covers the external surface of the epiphyses –Made of hyaline cartilage –Decreases friction at joint surfaces 13

Gross Anatomy of a Long Bone Diagram on p. 118 •Periosteum –Outside covering of the diaphysis –Fibrous connective tissue membrane •Sharpey’s fibers –Secure periosteum to underlying bone •Endosteum - Inner lining of the medullary cavity •Arteries, veins, nerves –Found in the Haversian and Volkman canal systems within the compact bone. 14

Bone Development and Growth •During development, cartilage is replaced by bone (ossification) •Cartilage remains in isolated areas –Bridge of the nose –Parts of ribs –Joints •Bones are remodeled and lengthened until growth stops –Bones change shape somewhat –Bones grow in width Diagram on p. 121 15

Bone Development and Growth •Epiphyseal plates allow for growth of long bone during childhood –New cartilage is continuously formed –Older cartilage becomes ossified •Cartilage is broken down •Bone replaces cartilage 16

Periosteum Compact bone Cartilage Medullary Cavity Cartilage Epiphyseal line Bone marrow Compact bone Diaphysis Epiphysis Compact bone Periosteum Blood vessels Spongy bone Epiphysis Sharpey's fibers Spongy bone

Divisions of the Skeleton •The Skeleton is divided into two major regions: a. Axial Skeleton b. Appendicular Skeleton •Axial Skeleton - longitudinal part of the body –Divided into three parts •Skull •Vertebral column •Bony thorax 19

Divisions of the Skeleton •Appendicular skeleton - appendages and joints –Limbs (appendages) –Pectoral girdle (shoulder, scapula, and clavicle) –Pelvic girdle (pelvis) 20

Divisions of the Skeleton Diagram p. 125 21

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Label Mr. Bones! Tibia Cranium Radius Sternum Sacrum Metacarpals Patella Fibula Humerus Ulna Clavicle Mandible Scapula Ribs Pelvic Metatarsals Vertebra Femur

patella humerus femur scapula radius vertebra metatarsals skull clavicle ulna tibia fibula pelvis metacarpals costals

Boneyard Bill's Body Parts Can you drag all the bones to their correct locations?

How fast can your class find the words? BONES, BONES, BONES As you find the bones, identify them on Steve! S T E R N U M Y E S J A W B O N E C L A V I C L E G O L S C H O O L R W P R S C A U P U L A B O A T E A T H A T S E D B P R U X L K E P N M A M Z C A I P A T E L L A S H I C L S S A F D O G I A I M U D A U A A B U E T E N E B S E I S R R M T N T R L S A M E I T D A H A B A A G S E A N O T U A A M C L G E N L E R M S E A L A R I B S D O T Y O S E U T A N T N E N I P S N R K B N L H V A L O S T B A N O F E M O S T B E E J S I V L E P F A V How fast can your class find the words? SPINE ULNA FIBULA FEMUR PATELLA CLAVICLE RADIUS STERNUM TIBIA PELVIS PHALANGES JAWBONE CRANIUM RIBS HUMERUS VERTEBRA SCAPULA

Axial Skeleton: The Skull •Two sets of bones –Cranium –Facial bones •Bones are joined by sutures (fixed, non-movable joints) •Only the mandible is attached by a freely movable joint 23

Axial Skeleton: The Skull 24 Diagram p. 126

Axial Skeleton: The Skull Diagram p. 129 Axial Skeleton: The Skull 25

Axial Skeleton: The Skull Diagram p. 127 Axial Skeleton: The Skull 26

Axial Skeleton: The Skull •Paranasal sinuses: Hollow portions of bones surrounding the nasal cavity –Functions •Lighten the skull •Give resonance and amplification to voice Diagram p. 128 27

Auditory meatus Mandibular ramus Mental foramen Frontal bone Nasal bone Ethmoid bone Lacrimal bone Maxilla Suture Mastoid process Temporal bone Occipital bone Sphenoid bone Suture Suture Mandible Parietal bone Zygomatic bone Styloid process

Practice Makes Perfect! Parietal bone Nasal bone Zygomatic bone Temporal bone Optic canal Inferior nasal concha Middle nasal concha Suture Lacrimal bone Ethmoid bone Mandible Vomer Alveolar margins Sphenoid bone Frontal bone Maxilla

Axial Skeleton: Hyoid Bone Diagram p. 130 ·The only bone that does not articulate with another bone ·Serves as a moveable base for the tongue Figure 5.12 30

Axial Skeleton: Vertebral Column Diagram p. 131 ·Vertebrae are separated by intervertebral discs composed of fibrocartilage ·The spine has a normal curvature ·Each vertebrae is given a name according to its location 31

Axial Skeleton: Vertebral Column 32 Diagram p. 133

Thoracic vertebrae Cervical vertebrae Sacrum Coccyx C1 Atlas Lumbar vertebrae C2 Axis

Appendicular Skeleton: Pectoral Girdle •Composed of two bones –Clavicle – collarbone –Scapula – shoulder blade •These bones allow the upper limb to have exceptionally free movement 36

Appendicular Skeleton: Pectoral Girdle (Shoulder) 37 Diagram p. 139

Appendicular Skeleton: Brachium Region ·The arm is formed by a single bone ·Humerus Diagram p. 140 38

Appendicular Skeleton: Antebrachium Region •The forearm has two bones •Ulna (side adjacent to little finger) •Radius (side adjacent to thumb) 39 Diagram p. 140

Appendicular Skeleton: Carpus, Manus, and Digits Region ·The hand ·Carpals – wrist ·Metacarpals – palm ·Phalanges – fingers 40 Diagram p. 141

Appendicular Skeleton: Pelvic Girdle •Hip bones •Composed of three pair of fused bones –Ilium –Ischium –Pubic bone •The total weight of the upper body rests on the pelvis •Protects several organs –Reproductive organs –Urinary bladder –Part of the large intestine 41

Appendicular Skeleton: Pelvic Girdle The sacrum and coccyx are part of the axial skeleton not appendicular skeleton. 42 Diagram p. 142

Appendicular Skeleton: Pelvic Girdle Coxal Bone Structure 43 Diagram p. 142

Appendicular Skeleton: Pelvic Girdle Male and Female Pelvis Comparison Diagram p. 142 44

Appendicular Skeleton: Femoral Region ·The thigh has one bone ·Femur – thigh bone 45 Diagram p. 144

Appendicular Skeleton: Patellar and Crural Regions ·The leg has two bones ·Tibia ·Fibula 46 Diagram p. 144

Appendicular Skeleton: Tarsal, Pes, and Digits Regions ·The foot ·Tarsus – ankle ·Metatarsals – sole ·Phalanges – toes 47 Diagram p. 145

Word Sort! Arrange the words into categories! Zygomatic bone Occipital bone Scapula Spongy Sphenoid bone Sternum Suture Femur Carpals Lacunae Temporal bone Osteoblast Ossification Cartilage Lumbar Vertebra Lamella Humerus Osteoclast Marrow Cervical Frontal bone Central canal Phalanges Epiphysis Pelvis Maxilla Patella Nasal bone Volkmann's canal Ethmoid bone Costals Parietal bone Cranium Diaphysis Compact Mandible

Articulations: Joints •A joint is a location where two or more bones meet. •Functions of joints –Hold bones together –Allow for mobility 49

Types of Joints •Ways joints are classified structurally: •Ways joints are classified functionally: •Synarthroses – immovable •Amphiarthroses – slightly moveable •Diarthroses – freely moveable •Ways joints are classified structurally: –Fibrous joints •Generally immovable (sutures of skull) –Cartilaginous joints •Immovable or slightly moveable (vertebral disc) –Synovial joints •Freely moveable (shoulder, pelvis, knee, elbow, digits) •Articulating bones are separated by a joint cavity •Synovial fluid is found in the joint cavity 50

Anatomy of Synovial Joints •Articular cartilage – (hyaline) covers ends of bones •Fibrous articular capsule – enclose joint surfaces; lined with synovial membrane •Joint cavity – cavity between bones of a joint containing a lubricating fluid called synovial fluid •Ligaments – reinforce the joint 51

Structure of a Synovial Joint Figure 5.28 52 Diagram p. 149

Type of Synovial Joints 53 Diagram p. 151

Types of Synovial Joints 54 Diagram p. 151

Gliding Pivot Hinge Ball and Socket Identify the type of joint in the diagrams.

What joint(s) is she using? Gliding Ball and Socket Hinge & Pivot

Diseases and Disorders of the Skeletal System •A fracture is 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 55

Diseases and Disorders of the Skeletal System •Open reduction – surgery is needed to secure the bones together with pins or wires. •Closed reduction – bone ends coaxed back into position by physician 56

Diseases and Disorders of the Skeletal System Diagram p. 123 57

Diseases and Disorders of the Skeletal System: Fractures Identify the fractures. Simple Greenstick radius Simple Spiral fibula Compound Fracture tibia and fibula Comminuted Fracture radius 58 X - Ray NQ

Diseases and Disorders of the Skeletal System •Osteoporosis: afflicts both men and women but most common in post menopausal women –Bone tissue becomes brittle and breaks easily with little applied stress –Cause - loss of calcium from bone matrix 59