chapter 6 the skeletal system. elsevier items and derived items © 2008, 2004 by mosby, inc., an...
TRANSCRIPT
Chapter 6Chapter 6The Skeletal SystemThe Skeletal System
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 2
FUNCTIONS OF THE SKELETAL FUNCTIONS OF THE SKELETAL SYSTEMSYSTEM
Supports and gives shape to the bodySupports and gives shape to the body Protects internal organsProtects internal organs Helps make movements possibleHelps make movements possible Stores calciumStores calcium Hemopoiesis, or blood cell formationHemopoiesis, or blood cell formation
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 3
TYPES OF BONESTYPES OF BONES
Four major types, according to overall Four major types, according to overall shape of the boneshape of the bone Long—Example: humerus (upper arm)Long—Example: humerus (upper arm) Short—Example: carpals (wrist)Short—Example: carpals (wrist) Flat—Example: frontal (skull)Flat—Example: frontal (skull) Irregular—Example: vertebrae (spinal cord)Irregular—Example: vertebrae (spinal cord)
Some also recognize a sesamoid (round) Some also recognize a sesamoid (round) bone categorybone category Example: patella (kneecap)Example: patella (kneecap)
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 4
STRUCTURE OF LONG BONESSTRUCTURE OF LONG BONES
Structural components (Figure 6-1)Structural components (Figure 6-1) Diaphysis or shaft—hollow tube of hard Diaphysis or shaft—hollow tube of hard
compact bonecompact bone Medullary cavity—hollow area inside diaphysis Medullary cavity—hollow area inside diaphysis
bone that contains yellow marrowbone that contains yellow marrow Epiphyses, or ends of the bone—spongy bone Epiphyses, or ends of the bone—spongy bone
that contains red bone marrowthat contains red bone marrow Articular cartilage—covers epiphyses and Articular cartilage—covers epiphyses and
functions as a cushionfunctions as a cushion Periosteum—strong membrane covering bone Periosteum—strong membrane covering bone
everywhere except at joint surfaceseverywhere except at joint surfaces Endosteum—lining of medullary cavityEndosteum—lining of medullary cavity
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 5
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 6
MICROSCOPIC STRUCTURE OF BONE MICROSCOPIC STRUCTURE OF BONE AND CARTILAGEAND CARTILAGE
Bone types (Figure 6-2)Bone types (Figure 6-2) SpongySpongy
• Texture results from needlelike threads of bone called Texture results from needlelike threads of bone called trabeculaetrabeculae surrounded by a network of open spaces surrounded by a network of open spaces
• Found in epiphyses of bonesFound in epiphyses of bones
• Spaces contain red bone marrowSpaces contain red bone marrow CompactCompact
• Structural unit is an osteon—calcified matrix arranged in Structural unit is an osteon—calcified matrix arranged in multiple layers or rings called multiple layers or rings called concentric lamellaconcentric lamella
• Composed of osteocytes, lacunae, and canaliculiComposed of osteocytes, lacunae, and canaliculi
• Covered by periosteumCovered by periosteum
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 7
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 8
MICROSCOPIC STRUCTURE OF BONE MICROSCOPIC STRUCTURE OF BONE AND CARTILAGEAND CARTILAGE
Cartilage (Figure 6-4)Cartilage (Figure 6-4) Cell type called Cell type called chondrocytechondrocyte Matrix is gel-like and lacks blood vesselsMatrix is gel-like and lacks blood vessels
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 9
BONE FORMATION AND GROWTH BONE FORMATION AND GROWTH (Figures 6-5 and 6-6)(Figures 6-5 and 6-6)
Early bone development (before birth) Early bone development (before birth) consists of cartilage and fibrous structuresconsists of cartilage and fibrous structures
Cartilage models gradually replaced by Cartilage models gradually replaced by calcified bone matrix—process called calcified bone matrix—process called endochondral ossificationendochondral ossification
Osteoblasts form new bone, and Osteoblasts form new bone, and osteoclasts resorb boneosteoclasts resorb bone
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 10
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 11
DIVISIONS OF SKELETONDIVISIONS OF SKELETON
Skeleton composed of the following divisions Skeleton composed of the following divisions and their subdivisions:and their subdivisions: Axial skeletonAxial skeleton
SkullSkull Spine (vertebral column)Spine (vertebral column) ThoraxThorax
Appendicular skeletonAppendicular skeleton Upper extremities, including shoulder (pectoral) Upper extremities, including shoulder (pectoral)
girdlegirdle Lower extremities, including hip (pelvic) girdleLower extremities, including hip (pelvic) girdle
Location and description of bones—see Location and description of bones—see Figures 6-7 to 6-17 and Tables 6-2 to 6-6Figures 6-7 to 6-17 and Tables 6-2 to 6-6
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 12
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 13
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 14
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 15
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 16
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 17
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 18
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 19
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 20
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 21
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 22
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 23
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 24
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 25
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 26
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 27
DIFFERENCES BETWEEN A MAN’S AND A DIFFERENCES BETWEEN A MAN’S AND A WOMAN’S SKELETONWOMAN’S SKELETON
Size—male skeleton generally largerSize—male skeleton generally larger Shape of pelvis—male pelvis deep and Shape of pelvis—male pelvis deep and
narrow; female pelvis broad and shallownarrow; female pelvis broad and shallow Size of pelvic inlet—female pelvic inlet Size of pelvic inlet—female pelvic inlet
generally wider, normally large enough for generally wider, normally large enough for baby’s head to pass through it (Figure 6-baby’s head to pass through it (Figure 6-18)18)
Pubic angle—angle between pubic bones Pubic angle—angle between pubic bones of female generally widerof female generally wider
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 28
JOINT (ARTICULATIONS)JOINT (ARTICULATIONS)
Every bone except the hyoid (which anchors the tongue) connects to Every bone except the hyoid (which anchors the tongue) connects to at least one other boneat least one other bone Kinds of joints (Figures 6-19 to 6-21)Kinds of joints (Figures 6-19 to 6-21)
Synarthroses (no movement)—fibrous connective tissue grows Synarthroses (no movement)—fibrous connective tissue grows between articulating bones; example: sutures of skullbetween articulating bones; example: sutures of skull
Amphiarthroses (slight movement)—cartilage connects articulating Amphiarthroses (slight movement)—cartilage connects articulating bones; example: symphysis pubisbones; example: symphysis pubis
Diarthroses (free movement)—most joints belong to this classDiarthroses (free movement)—most joints belong to this class• Structures of freely movable joints—joint capsule and ligaments hold Structures of freely movable joints—joint capsule and ligaments hold
adjoining bones together but permit movement at jointadjoining bones together but permit movement at joint
• Articular cartilage—covers joint ends of bones and absorbs jointsArticular cartilage—covers joint ends of bones and absorbs joints
• Synovial membrane—lines joint capsule and secretes lubricating fluidSynovial membrane—lines joint capsule and secretes lubricating fluid
• Joint cavity—space between joint ends of bonesJoint cavity—space between joint ends of bones
Types of freely movable joints—ball-and-socket, hinge, pivot, Types of freely movable joints—ball-and-socket, hinge, pivot, saddle, gliding, and condyloidsaddle, gliding, and condyloid
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 29
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 30
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 31
Elsevier items and derived items © 2008, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 32