Skeletal System: Bones and Joints PDF

Seeley’s ESSENTIALS OF...

Seeley’s ESSENTIALS OF Anatomy & Physiology Tenth Edition Cinnamon Vanputte Jennifer Regan Andrew Russo See separate PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes. © 2019 McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior  2 Chapter 6 Skeletal System:Bones and Joints Lecture Outline © 2019 McGraw-Hill Education  3 Components of Skeletal System  Bones  Tendons  Ligaments  Cartilages © 2019 McGraw-Hill Education  4 Bones of the Skeletal System Figure © 2019 McGraw-Hill Education 6.11  5 Skeletal System Functions  Support  Protect  Movement  Storage  Blood cell production © 2019 McGraw-Hill Education  6 Extracellular Matrix 1  Bone, cartilage, tendons, and ligaments of the skeletal system are all connective tissues.  Their characteristics are largely determined by the composition of their extracellular matrix.  The matrix always contains collagen, ground substance, and other organic molecules, as well as water and minerals. © 2019 McGraw-Hill Education  7 Extracellular Matrix 2 Collagen  is a tough, ropelike protein. Proteoglycans  are large molecules consisting of many polysaccharides attaching to and encircling core proteins.  form large aggregates and attract water. © 2019 McGraw-Hill Education  8 Extracellular Matrix 2 Tendons and Ligaments  Their extracellular matrix contains large amounts of collagen fibers, making these structures very tough, like ropes or cables. © 2019 McGraw-Hill Education  9 Cartilage Extracellular Matrix  contains collagen and proteoglycans.  Collagen makes cartilage tough, whereas the water-filled proteoglycans make it smooth and resilient.  As a result, cartilage is relatively rigid, but it springs back to its original shape after being bent or slightly compressed. © 2019 McGraw-Hill Education  10 Bone Extracellular Matrix  contains collagen and minerals, including calcium and phosphate.  The ropelike collagen fibers lend flexible strength to the bone.  The mineral component gives bone compression (weight-bearing) strength.  Most of the mineral in bone is in the form of calcium phosphate crystals called hydroxyapatite. © 2019 McGraw-Hill Education  11 Shape Classification of Bones 1 There are four bone shape classifications: long, short, flat, and irregular. Long bones are longer than they are wide; examples are upper and lower limb bones. Short bones are approximately as wide as they are long; examples are the bones of the wrist and ankle. © 2019 McGraw-Hill Education  12 Shape Classification of Bones 2 Flat bones have a relatively thin, flattened shape; examples are bones of the skull and sternum. Irregular bones include the vertebrae and facial bones, which have shapes that do not fit readily into the other three categories. © 2019 McGraw-Hill Education  13 Long Bone Structures 1 Diaphysis  Shaft  compact bone tissue (on outside) Epiphysis  ends spongy bone tissue Figure © 2019 McGraw-Hill Education 6.2a  14 Long Bone Structures 1 Articular cartilage  covers epiphyses  reduces friction Figure © 2019 McGraw-Hill Education 6.2a  15 Long Bone Structures 2 Epiphyseal plate: site of growth between diaphysis and epiphysis Medullary cavity: center of diaphysis red or yellow Figure © 2019 McGraw-Hill Education 6.2b  16 Long Bone Structures 3 Periosteum  membrane around bone’s outer surface Endosteum:  membrane that lines Figure medullary © 2019 McGraw-Hill Education 6.2a  17 Structure of Long Bone Figure © 2019 McGraw-Hill Education 6.2  18 Bone Marrow 1 Bones contain cavities, such as the large medullary cavity in the diaphysis, as well as smaller cavities in the epiphyses of long bones and in the interior of other bones. These spaces are filled with soft tissue called marrow. Red marrow is the location of blood forming cells. Yellow marrow is mostly fat. © 2019 McGraw-Hill Education  19 Bone Marrow 2 In newborns most bones have blood making red bone marrow. In adults red marrow in the diaphysis is replaced by yellow bone marrow. In adults most red bone marrow is in the flat bones and the long bones of the femur and humerus. © 2019 McGraw-Hill Education  20 Structure of Bone Tissue Figure © 2019 McGraw-Hill Education 6.3 (a) ©Trent Stephens  21 Bone Cells Osteoblasts: responsible for the formation of bone and the repair and remodeling of bone. Osteocytes: cells that maintain bone matrix and form from osteoblast after bone matrix has surrounded it. Osteoclasts: contribute to bone repair and remodeling by removing existing bone, called bone reabsorption. © 2019 McGraw-Hill Education  22 Compact Bone Tissue 1 Location: outer part of diaphysis (long bones) and thinner surfaces of other bones Osteon: structural unit of compact bone includes lamella, lacunae, canaliculus, central canal, osteocytes Figure © 2019 McGraw-Hill Education 6.2c  23 Compact Bone Tissue 2 Lacunae: spaces between lamella Canaliculus: tiny canals transport nutrients and remove waste Central canal: center of osteon Figure © 2019 McGraw-Hill Education 6.2c  24 Spongy (Cancellous) Bone Tissue Spongy bone It is located at the epiphyses of long bones and center of other bones. It has trabeculae(beams), which are interconnecting rods, and spaces that contain marrow. It has no osteons. © 2019 McGraw-Hill Education  25 Spongy Bone Tissue Figure © 2019 McGraw-Hill Education 6.4  26 Bone Formation Ossification is the formation of bone by osteoblasts. Bone formation that occurs within connective tissue membranes is called intramembranous ossification. Bone formation that occurs inside hyaline cartilage is called endochondral ossification. Both types of bone formation result in compact and spongy bone. © 2019 McGraw-Hill Education  27 Intramembranous Ossification 1 Intramembranous ossification occurs when osteoblasts begin to produce bone within connective tissue. This occurs primarily in the bones of the skull. Osteoblasts line up on the surface of connective tissue fibers and begin depositing bone matrix to form trabeculae. © 2019 McGraw-Hill Education  28 Intramembranous Ossification 2 The process begins in areas called ossification centers and the trabeculae radiate out from the centers. Usually, two or more ossification centers exist in each flat skull bone and mature skull bones result from fusion of these centers as they enlarge. The trabeculae are constantly remodeled and they may enlarge or be replaced by compact bone. © 2019 McGraw-Hill Education  29 Bone Formation in the Fetus Figure © 2019 McGraw-Hill Education 6.5 (b) ©Biophoto Associates/Science Source  30 Endochondral Ossification Endochondral bone formation is bone formation within a cartilage model. The cartilage model is replaced by bone. Initially formed is a primary ossification center, which is bone formation in the diaphysis of a long bone. A secondary ossification center is bone formation in the epiphysis. © 2019 McGraw-Hill Education  31 Steps in Endochondral Ossification 1. Chondroblasts build a cartilage model, the chondroblasts become chondrocytes. 2. Cartilage model calcifies (hardens). 3. Osteoblasts invade calcified cartilage and a primary ossification center forms diaphysis. 4. Secondary ossification centers form epiphysis. © 2019 McGraw-Hill Education  Endochondral Ossification of a Long 32 Bone Figure © 2019 McGraw-Hill Education 6.6  33 Bone Growth in Width Bone growth occurs by the deposition of new bone lamellae onto existing bone or other connective tissue. As osteoblasts deposit new bone matrix on the surface of bones between the periosteum and the existing bone matrix, the bone increases in width, or diameter. This process is called appositional growth. © 2019 McGraw-Hill Education  34 Bone Growth in Length 1 Growth in the length of a bone, which is the major source of increased height in an individual, occurs in the epiphyseal plate. This type of bone growth occurs through endochondral ossification. Chondrocytes increase in number on the epiphyseal side of the epiphyseal plate. © 2019 McGraw-Hill Education  35 Bone Growth in Length 2 Then the chondrocytes enlarge and die. The cartilage matrix becomes calcified. Much of the cartilage that forms around the enlarged cells is removed by osteoclasts, and the dying chondrocytes are replaced by osteoblasts. © 2019 McGraw-Hill Education  36 Bone Growth in Length 3 The osteoblasts start forming bone by depositing bone lamellae on the surface of the calcified cartilage. This process produces bone on the diaphyseal side of the epiphyseal plate. © 2019 McGraw-Hill Education  37 Endochondral Bone Growth Figure © 2019 McGraw-Hill Education 6.7 (a) ©Ed Reschke/Photolibrary/Getty Images; (c) ©Biophoto  38 Bone Remodeling Bone remodeling involves: removal of existing bone by osteoclasts and deposition of new bone by osteoblasts occurs in all bones responsible for changes in bone shape, bone repair, adjustment of bone to stress, and calcium ion regulation © 2019 McGraw-Hill Education  39 Bone Repair 1 1. Broken bone causes bleeding and a blood clot forms. 2. Callus forms which is a fibrous network between 2 fragments. 3. Cartilage model forms first then, osteoblasts enter the callus and form cancellous bone this continues for 4-6 weeks after injury. 4. Cancellous bone is slowly remodeled to form compact and cancellous © 2019 McGraw-Hill Education  40 Bone Repair 2 Figure © 2019 McGraw-Hill Education 6.8 (a) (top and bottom) ©Andrew F. Russo  41 Bone and Calcium Homeostasis Bone is a major storage site for calcium Movement of calcium in and out of bone helps determine blood levels of calcium Calcium moves into bone as osteoblasts build new bone Calcium move out of bone as osteoclasts break down bone Calcium homeostasis is maintained by © 2019 McGraw-Hill Education  42 Calcium Homeostasis Figure © 2019 McGraw-Hill Education 6.10  43 Bone Anatomical Terms 1 Foramen: hole Example - foramen magnum Fossa: depression Example - glenoid fossa Process: projection Example - mastoid process © 2019 McGraw-Hill Education  44 Bone Anatomical Terms 2 Condyle: smooth, rounded end Example - occipital condyle Meatus: canal-like passageway Example - external auditory meatus Tubercle: lump of bone Example - greater tubercle © 2019 McGraw-Hill Education  45 Axial Skeleton 1 The axial skeleton is composed of the skull, the vertebral column, and the thoracic cage. The skull has 22 bones divided into those of the braincase and those of the face. The braincase, which encloses the cranial cavity, consists of 8 bones that immediately surround and protect the brain. © 2019 McGraw-Hill Education  46 Axial Skeleton 2 Thirteen of the facial bones are rather solidly connected to form the bulk of the face. The mandible, however, forms a freely movable joint with the rest of the skull. There are also three auditory ossicles in each middle ear (six total). © 2019 McGraw-Hill Education  47 Cranial Bones 1 Frontal bone Anterior part of cranium Parietal bones Sides and roof of cranium Occipital bones Posterior portion and floor of cranium Temporal bones Inferior to parietal bones on each side of the cranium Temporomandibular joint © 2019 McGraw-Hill Education  48 Cranial Bones 2 Sphenoid bone Forms part of cranium floor, lateral posterior portions of eye orbits, lateral portions of cranium anterior to temporal bones Sella turcica Ethmoid bone Anterior portion of cranium, including medial surface of eye orbit and roof of nasal cavity © 2019 McGraw-Hill Education  49 Facial Bones 1 Maxillae Form upper jaw, anterior portion of hard palate, part of lateral walls of nasal cavity, floors of eye orbits Maxillary sinus Palatine bones Form posterior portion of hard palate, lateral wall of nasal cavity © 2019 McGraw-Hill Education  50 Facial Bones 2 Zygomatic bones Cheek bones Also form floor and lateral wall of each eye orbit Lacrimal bones Medial surfaces of eye orbits Nasal bones Form bridge of nose © 2019 McGraw-Hill Education  51 Facial Bones 3 Vomer In midline of nasal cavity Forms nasal septum with the ethmoid bone Inferior nasal conchae Attached to lateral walls of nasal cavity Mandible Lower jawbone © 2019 McGraw-Hill Education  52 The Skull 1 Figure © 2019 McGraw-Hill Education 6.12  53 The Skull 2 Figure © 2019 McGraw-Hill Education 6.13 (b) ©Eric Wise  54 The Skull 3 Figure © 2019 McGraw-Hill Education 6.15 (b) ©McGraw-Hill Education/Christine Eckel  55 The Skull 4 Figure © 2019 McGraw-Hill Education 6.16 (b) ©McGraw-Hill Education/Christine Eckel  56 Paranasal Sinuses 1 Several of the bones associated with the nasal cavity have large cavities within them, called the paranasal sinuses which open into the nasal cavity. The paranasal sinuses are: Frontal Ethmoid Sphenoid Maxillary © 2019 McGraw-Hill Education  57 Paranasal Sinuses 2 Figure © 2019 McGraw-Hill Education 6.14  58 Hyoid Bone 1 The hyoid bone is an unpaired, U- shaped bone that is not part of the skull and has no direct bony attachment to the skull or any other bones. The hyoid bone has the unique distinction of being the only bone in the body that does not articulate with another bone. The hyoid bone provides an attachment for some tongue muscles, and it is an © 2019 McGraw-Hill Education  59 Hyoid Bone 2 Figure © 2019 McGraw-Hill Education 6.17  60 Vertebral Column 1 The vertebral column, or spine, is the central axis of the skeleton, extending from the base of the skull to slightly past the end of the pelvis. In adults, it usually consists of 26 individual bones, grouped into five regions. The adult vertebral column has four major curvatures: cervical, thoracic, lumbar and sacrococcygeal. The cervical region curves anteriorly. The thoracic region curves posteriorly. The lumbar region curves anteriorly © 2019 McGraw-Hill Education  61 Vertebral Column 2  7 cervical vertebra  12 thoracic vertebra  5 lumbar vertebra  1 sacrum  1 coccyx Atlas: 1st vertebra holds head Axis: 2nd vertebra rotates head © 2019 McGraw-Hill Education  62 Functions of Vertebral Column Supports body weight Protects the spinal cord Allows spinal nerves to exit the spinal cord Provides a site for muscle attachment Provides movement of the head and trunk © 2019 McGraw-Hill Education  63 Vertebral Column 3 Figure © 2019 McGraw-Hill Education 6.18  64 Vertebra Figure © 2019 McGraw-Hill Education 6.19  65 Regional Differences in Vertebrae Figure © 2019 McGraw-Hill Education 6.20 (a) ©McGraw-Hill Education/Christine Eckel  66 Sacrum Figure © 2019 McGraw-Hill Education 6.21 (c) ©McGraw-Hill Education/Christine Eckel  67 Thoracic Cage 1 Protects vital organs 12 pair of ribs Sternum: breastbone True ribs: attach directly to sternum by cartilage False ribs: attach indirectly to sternum by cartilage Floating ribs: not attached to sternum © 2019 McGraw-Hill Education  68 Thoracic Cage 2 Figure © 2019 McGraw-Hill Education 6.22  69 Bones of the Pectoral Girdle Scapula: shoulder blade Clavicle: collar bone © 2019 McGraw-Hill Education  70 Pectoral Girdle Figure © 2019 McGraw-Hill Education 6.23  71 Scapula and Clavicle Figure © 2019 McGraw-Hill Education 6.25 (d) ©Trent Stephens  72 Upper Limb Bones 1 Humerus: upper limb Ulna: forearm Radius: forearm Carpals: wrist Metacarpals: hand © 2019 McGraw-Hill Education  73 Upper Limb Bones 2 Figure © 2019 McGraw-Hill Education 6.23  74 The Humerus Figure © 2019 McGraw-Hill Education 6.27 (c) ©McGraw-Hill Education/ Christine  75 Ulna and Radius Figure © 2019 McGraw-Hill Education 6.28 (b) ©McGraw-Hill Education/Christine Eckel  76 Bones of the Wrist and Hand Figure © 2019 McGraw-Hill Education 6.29  77 Pelvic Girdle Where lower limbs attach to the body Pelvis: includes pelvic girdle and coccyx Ischium: inferior and posterior region Ilium: most superior region Acetabulum: hip socket (joint) © 2019 McGraw-Hill Education  78 Pelvis Figure © 2019 McGraw-Hill Education 6.32  79 Hip Bones Figure © 2019 McGraw-Hill Education 6.33 (c) ©McGraw-Hill Education/Christine Eckel  Comparison of the Male Pelvis 80 to the Female Pelvis Figure © 2019 McGraw-Hill Education 6.34  81 Lower Limb Bones 1 Femur: thigh Patella: knee cap Tibia: large lower leg Fibula: small lower leg © 2019 McGraw-Hill Education  82 Lower Limb Bones 2 Tarsals: ankle Metatarsals: foot Phalanges: toes and fingers © 2019 McGraw-Hill Education  83 Lower Limb Bones 3 Figure © 2019 McGraw-Hill Education 6.31  84 Bones of the Thigh Figure © 2019 McGraw-Hill Education 6.35 (b) ©McGraw-Hill Education/Christine Eckel  85 Bones of the Leg Figure © 2019 McGraw-Hill Education 6.36 (b) ©McGraw-Hill Education/Christine Eckel  86 Bones of the Foot Figure © 2019 McGraw-Hill Education 6.37  87 Articulations  Articulations (joints) are where two bones come together.  Joints can be classified structurally as fibrous, cartilaginous, or synovial,  Joints are also be classified in functional categories according to their degree of motion as synarthroses, amphiarthroses, or diarthroses. © 2019 McGraw-Hill Education  88 Structural Classification of Joints Fibrous joint  united by fibrous connective tissue  subclasses are sutures, syndesmosis, and gomphoses Cartilaginous joint  united by means of cartilage  subclasses are synchondroses and symphysis © 2019 McGraw-Hill Education  89 Structural Classification of Joints Synovial  joined by a fluid cavity  Most joints of the appendicular skeleton © 2019 McGraw-Hill Education  90 Functional Classification of Joints Synarthrosis:  non-movable joint  Example – skull bone articulations Amphiarthrosis:  slightly movable joint  Example - between vertebrae © 2019 McGraw-Hill Education  91 Functional Classification of Joints Diarthrosis  freely movable joint  Example - knee, elbow, and wrist articulations © 2019 McGraw-Hill Education  92 Fontanels and Sutures Figure © 2019 McGraw-Hill Education 6.39  93 Structure of a Synovial Joint Figure © 2019 McGraw-Hill Education 6.40  94 Types of Synovial Joints Figure © 2019 McGraw-Hill Education 6.41  95 Types of Movement 1 Flexion: bending Extension: straightening Abduction: movement away from midline Adduction: movement toward the midline Pronation: rotation of the forearm with palms down Supination: rotation of the forearm with palms up Rotation: movement of a structure about the long axis © 2019 McGraw-Hill Education  96 Types of Movement 2 © 2019 McGraw-Hill Education  Effects of Aging on the Skeletal System 97 and Joints 1. Decreased Collagen Production 2. Loss of Bone Density 3. Degenerative Changes © 2019 McGraw-Hill Education