Skeletal System PDF

SKELETAL SYSTEM INALVEZ, Daryl Christian E, MD, RND  The Skeletal System  Parts of the skeletal system  Bones (skeleton)  Joints  Cartilages  Ligaments  Two subdivisions of the skeleton 1.Axial skeleton 2.Appendicula...

SKELETAL SYSTEM INALVEZ, Daryl Christian E, MD, RND  The Skeletal System  Parts of the skeletal system  Bones (skeleton)  Joints  Cartilages  Ligaments  Two subdivisions of the skeleton 1.Axial skeleton 2.Appendicular skeleton © 2018 Pearson Education, Ltd.  Functions of the Bones  Support the body  Protect soft organs  Skull and vertebrae protect brain and spinal cord  Rib cage protects thoracic cavity organs  Attached skeletal muscles allow movement  Store minerals and fats  Calcium and phosphorus  Fat in the internal marrow cavity  Blood cell formation (hematopoiesis) © 2018 Pearson Education, Ltd.  Classification of Bones  The adult skeleton has 206 bones  Two basic types of osseous (bone) tissue 1. Compact bone  Dense, smooth, and homogeneous 2. Spongy bone  Small needlelike pieces of bone  Many open spaces © 2018 Pearson Education, Ltd. Figure 5.1 Flat bones consist of a layer of spongy bone sandwiched between two thin layers of compact bone. Spongy bone Compact bone © 2018 Pearson Education, Ltd.  Classification of Bone  Bones are classified on the basis of shape into four groups  Long  Flat  Short  Irregular © 2018 Pearson Education, Ltd. Figure 5.2 Classification of bones on the basis of shape. (b) Flat bone (sternum) (a) Long bone (humerus) (d) Irregular bone (vertebra), right lateral (c) Short bone (talus) view © 2018 Pearson Education, Ltd.  Classification of Bones  Long bones  Typically longer than they are wide  Shaft with enlarged ends  Contain mostly compact bone; spongy bone at ends  All of the bones of the limbs (except wrist, ankle, and kneecap bones) are long bones  Examples:  Femur  Humerus © 2018 Pearson Education, Ltd. Figure 5.2a Classification of bones on the basis of shape. (a) Long bone (humerus) © 2018 Pearson Education, Ltd.  Classification of Bones  Flat bones  Thin, flattened, and usually curved  Two thin layers of compact bone sandwich a layer of spongy bone between them  Examples:  Most bones of the skull  Ribs  Sternum © 2018 Pearson Education, Ltd. Figure 5.2b Classification of bones on the basis of shape. (b) Flat bone (sternum) © 2018 Pearson Education, Ltd.  Classification of Bones  Short bones  Generally cube-shaped  Contain mostly spongy bone with an outer layer of compact bone  Sesamoid bones are a type of short bone that form within tendons (patella)  Examples:  Carpals (wrist bones)  Tarsals (ankle bones) © 2018 Pearson Education, Ltd. Figure 5.2c Classification of bones on the basis of shape. (c) Short bone (talus) © 2018 Pearson Education, Ltd.  Classification of Bones  Irregular bones  Irregular shape  Do not fit into other bone classification categories  Examples:  Vertebrae  Hip bones © 2018 Pearson Education, Ltd. Figure 5.2d Classification of bones on the basis of shape. (d)Irregular bone (vertebra), right lateral view © 2018 Pearson Education, Ltd. © 2018 Pearson Education, Ltd.  Structure of Bone  Long bone anatomy  Diaphysis (shaft)  Makes up most of bone’s length  Composed of compact bone  Periosteum  Outside covering of the diaphysis  Fibrous connective tissue membrane  Perforating (Sharpey’s) fibers secure periosteum to underlying bone © 2018 Pearson Education, Ltd. Figure 5.3a The structure of a long bone (humerus of arm). Articular cartilage Proximal epiphysis Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) Diaphysis Distal epiphysis (a) © 2018 Pearson Education, Ltd. Figure 5.3c The structure of a long bone (humerus of arm). Endosteum Yellow bone marrow Compact bone Periosteum Perforating (Sharpey’s) fibers Nutrient arteries (c) © 2018 Pearson Education, Ltd.  Structure of Bone  Long bone anatomy (continued)  Epiphysis (ends)  Composed mostly of spongy bone enclosed by thin layer of compact bone  Articular cartilage  Covers the external surface of the epiphyses  Made of hyaline cartilage  Decreases friction at joint surfaces © 2018 Pearson Education, Ltd. Figure 5.3b The structure of a long bone (humerus of arm). Articular cartilage Compact bone Spongy bone (b) © 2018 Pearson Education, Ltd.  Structure of Bone  Long bone anatomy (continued)  Epiphyseal line  Remnant of the epiphyseal plate  Seen in adult bones  Epiphyseal plate  Flat plate of hyaline cartilage seen in young, growing bone  Causes lengthwise growth of a long bone © 2018 Pearson Education, Ltd. Figure 5.3a The structure of a long bone (humerus of arm). Articular cartilage Proximal epiphysis Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) Diaphysis Distal epiphysis (a) © 2018 Pearson Education, Ltd.  Structure of Bone  Long bone anatomy (continued)  Endosteum  Lines the inner surface of the shaft  Made of connective tissue  Medullary cavity  Cavity inside the shaft  Contains yellow marrow (mostly fat) in adults  Contains red marrow for blood cell formation in infants until age 6 or 7 © 2018 Pearson Education, Ltd. Figure 5.3a The structure of a long bone (humerus of arm). Articular cartilage Proximal epiphysis Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) Diaphysis Distal epiphysis (a) © 2018 Pearson Education, Ltd.  Structure of Bone  Bone markings  Sites of attachments for muscles, tendons, and ligaments  Passages for nerves and blood vessels  Categories of bone markings  Projections or processes—grow out from the bone surface  Terms often begin with “T”  Depressions or cavities—indentations  Terms often begin with “F” © 2018 Pearson Education, Ltd. Table 5.1 Bone Markings (1 of 3) © 2018 Pearson Education, Ltd. Table 5.1 Bone Markings (2 of 3) © 2018 Pearson Education, Ltd. Table 5.1 Bone Markings (3 of 3) © 2018 Pearson Education, Ltd.  Structure of Bone  Microscopic anatomy of spongy bone  Composed of small, needlelike pieces of bone called trabeculae and open spaces  Open spaces are filled by marrow, blood vessels, and nerves © 2018 Pearson Education, Ltd. Figure 5.4a Microscopic structure of bone. Trabeculae of spongy bone Osteon (Haversian Perforating system) (Volkmann’s ) canalcontinues Blood vessel into medullary cavity containing marrow Blood vessel Lamellae Compact bone Central (Haversian) canal Perforating (Sharpey’s) fibers Periosteum Periosteal blood vessel (a ) © 2018 Pearson Education, Ltd.  Structure of Bone  Microscopic anatomy of compact bone  Osteocytes  Mature bone cells situated in bone matrix  Lacunae  Cavities in bone matrix that house osteocytes  Lamellae  Concentric circles of lacunae situated around the central (Haversian) canal © 2018 Pearson Education, Ltd.  Structure of Bone  Microscopic anatomy of compact bone (continued)  Central (Haversian) canal  Opening in the center of an osteon (Haversian system)  Runs lengthwise through bone  Carries blood vessels and nerves  Osteon (Haversian system)  A unit of bone containing central canal and matrix rings  Structural and functional unit of compact bone © 2018 Pearson Education, Ltd. Figure 5.4b Microscopic structure of bone. Lamella Osteocyte Canaliculus Lacuna Central Bone matrix (Haversian) canal (b) © 2018 Pearson Education, Ltd. Figure 5.4c Microscopic structure of bone. Osteon Interstitial lamellae Lacuna Central (Haversian) canal (c) © 2018 Pearson Education, Ltd.  Structure of Bone  Microscopic anatomy of compact bone (continued)  Canaliculi  Tiny canals  Radiate from the central canal to lacunae  Form a transport system connecting all bone cells to a nutrient supply  Perforating (Volkmann’s) canal  Canal perpendicular to the central canal  Carries blood vessels and nerves © 2018 Pearson Education, Ltd. Figure 5.4b Microscopic structure of bone. Lamella Osteocyte Canaliculus Lacuna Central Bone matrix (Haversian) canal (b) © 2018 Pearson Education, Ltd.  Structure of Bone  Bone is relatively lightweight and resists tension and other forces  Organic parts (collagen fibers) of the bone make bone flexible and have great tensile strength  Calcium salts deposited in the bone make bone hard to resist compression © 2018 Pearson Education, Ltd.  Bone Formation, Growth, and Remodeling  Bone formation and growth  Ossification is the process of bone formation  Occurs on hyaline cartilage models or fibrous membranes  Long bone growth involves two major phases © 2018 Pearson Education, Ltd.  Bone Formation, Growth, and Remodeling  Two major phases of ossification in long bones 1. Osteoblasts (bone-forming cells) cover hyaline cartilage model with bone matrix 2. In a fetus, the enclosed cartilage is digested away, opening up a medullary cavity © 2018 Pearson Education, Ltd. Figure 5.5 Stages of long-bone formation in an embryo, fetus, and young child. Articular cartilage Hyaline Spongy cartilage bone New center of bone growth New bone Epiphyseal forming plate cartilage Growth Medullary in bone cavity width Bone starting Invading to replace Growth blood cartilage in bone vessels length New bone Bone collar forming Hyaline Epiphyseal cartilage plate cartilage model In an embryo In a fetus In a child © 2018 Pearson Education, Ltd. Figure 5.6 Growth and remodeling of long bones. Slide 4 Bone growth Bone grows in length because: 1 Cartilage Articular cartilage grows here. Epiphyseal plate 2 Cartilage is replaced by bone here. 3 Cartilage grows here. © 2018 Pearson Education, Ltd.  Bone Formation, Growth, and Remodeling  By birth, most cartilage is converted to bone except for two regions in a long bone 1. Articular cartilages 2. Epiphyseal plates  New cartilage is formed continuously on external face of these two cartilages  Old cartilage is broken down and replaced by bony matrix © 2018 Pearson Education, Ltd. Figure 5.6 Growth and remodeling of long bones. Slide 8 Bone remodeling Growing shaft is remodeled as: Articular cartilage Epiphyseal plate 1 Bone is resorbed by osteoclasts here. 2 Bone is added (appositional growth) by osteoblasts 3 Bone is resorbed here. by osteoclasts here. © 2018 Pearson Education, Ltd.  Bone Formation, Growth, and Remodeling  Appositional growth  Bones grow in width  Osteoblasts in the periosteum add bone matrix to the outside of the diaphysis  Osteoclasts in the endosteum remove bone from the inner surface of the diaphysis  Bone growth is controlled by hormones, such as growth hormone and sex hormones © 2018 Pearson Education, Ltd.  Bone Formation, Growth, and Remodeling  Bones are remodeled throughout life in response to two factors 1. Calcium ion level in the blood determines when bone matrix is to be broken down or formed 2. Pull of gravity and muscles on the skeleton determines where bone matrix is to be broken down or formed © 2018 Pearson Education, Ltd.  Bone Formation, Growth, and Remodeling  Calcium ion regulation  Parathyroid hormone (PTH)  Released when calcium ion levels in blood are low  Activates osteoclasts (bone-destroying cells)  Osteoclasts break down bone and release calcium ions into the blood  Hypercalcemia (high blood calcium levels) prompts calcium storage to bones by osteoblasts © 2018 Pearson Education, Ltd.  Bone Fractures  Fracture: break in a bone  Types of bone fractures  Closed (simple) fracture is a break that does not penetrate the skin  Open (compound) fracture is a broken bone that penetrates through the skin © 2018 Pearson Education, Ltd.  Bone Fractures  Bone fractures are treated by reduction and immobilization  Closed reduction: bones are manually coaxed into position by physician’s hands  Open reduction: bones are secured with pins or wires during surgery  Healing time is 6–8 weeks © 2018 Pearson Education, Ltd.  Bone Fractures  Repair of bone fractures involves four major events  Hematoma (blood-filled swelling, or bruise) is formed  Fibrocartilage callus forms  Cartilage matrix, bony matrix, collagen fibers splint the broken bone  Bony callus replaces the fibrocartilage callus  Osteoblasts and osteoclasts migrate in  Bone remodeling occurs in response to mechanical stresses © 2018 Pearson Education, Ltd. Figure 5.7 Stages in the healing of a bone fracture. Hematoma External Bony callus callus of spongy bone New Internal blood vessels Healed callus fracture (fibrous tissue and Spongy bone cartilage) trabecula 1 Hematoma 2 Fibrocartilage 3 Bony callus 4 Bone remodeling forms. callus forms. forms. occurs. © 2018 Pearson Education, Ltd. Table 5.2 Common Types of Fractures © 2018 Pearson Education, Ltd.  Axial Skeleton  Forms the longitudinal axis of the body  Divided into three parts 1. Skull 2. Vertebral column 3. Bony thorax © 2018 Pearson Education, Ltd. Figure 5.8a The human skeleton. Cranium Skull Facial bones Clavicle Thoracic cage Scapula (ribs and Sternum sternum) Rib Humerus Vertebra Vertebra Radius l Ulna Sacru column m Carpals Phalanges Metacarpals Femur Patella Tibia Fibula Tarsals Metatarsals Phalanges (a) Anterior © 2018 Pearson Education, Ltd. view Figure 5.8b The human skeleton. Cranium Bones of pectoral Clavicle girdle Scapula Sternum Upper Rib limb Humerus Vertebr R a adius Bones of Ulna pelvic Carpals girdle Phalanges Metacarpals Femur Lower Tibia limb Fibula (b) Posterior view © 2018 Pearson Education, Ltd. © 2018 Pearson Education, Ltd.  Skull  Two sets of bones form the skull 1. Cranium bones enclose the brain 2. Facial bones  Hold eyes in anterior position  Allow facial muscles to express feelings  Bones are joined by sutures  Only the mandible is attached by a freely movable joint © 2018 Pearson Education, Ltd.  Skull  8 cranial bones protect the brain 1 Frontal bone 2 Occipital bone 3 Ethmoid bone 4 Sphenoid bone 5, 6 Parietal bones (pair) 7, 8 Temporal bones (pair) © 2018 Pearson Education, Ltd.  Skull  14 facial bones 1, 2 Maxillae (pair) 3, 4 Palatine bones (pair) 5, 6 Lacrimal bones (pair) 7, 8 Zygomatic bones (pair) 9, 10 Nasal bones (pair) 11 Vomer bone 12, 13 Inferior nasal conchae (pair) 14 Mandible © 2018 Pearson Education, Ltd. Figure 5.9 Human skull, lateral view. Coronal suture Frontal bone Parietal bone Sphenoid bone Temporal bone Ethmoid bone Lambdoid Lacrimal bone suture Squamous suture Nasal bone Occipital bone Zygomatic process Zygomatic bone Maxilla External acoustic meatus Mastoid process Alveolar processes Styloid process Mandible (body) Mental foramen Mandibular ramus © 2018 Pearson Education, Ltd. Figure 5.10 Human skull, superior view (top of cranium removed). Frontal bone Cribriform plate Ethmoid Crista galli bone Sphenoid bone Optic canal Sella turcica Foramen ovale Temporal bone Jugular foramen Internal acoustic meatus Parietal bone Occipital bone Foramen magnum © 2018 Pearson Education, Ltd. Figure 5.11 Human skull, inferior view (mandible removed). Maxilla Hard (palatine process) Incisive fossa palate Palatine bone Maxilla Zygomatic bone Sphenoid bone Temporal bone (greater wing) (zygomatic process) Foramen ovale Vomer Mandibular fossa Carotid canal Styloid process Mastoid process Jugular foramen Temporal bone Occipital condyle Parietal bone Foramen magnum Occipital bone © 2018 Pearson Education, Ltd. Figure 5.12 Human skull, anterior and posterior views. Coronal suture Frontal bone Parietal bone Nasal bone Superior orbital fissure Sphenoid bone Optic canal Ethmoid bone Temporal bone Lacrimal bone Zygomatic bone Infraorbital Middle nasal concha foramen of ethmoid bone Maxilla Inferior nasal concha Vomer Mandible Alveolar processes Mental foramen Sagittal suture Anterior view Parietal bone Lambdoid suture Occipital bone Mastoid process of temporal bone Posterior view © 2018 Pearson Education, Ltd.  Skull  Paranasal sinuses  Hollow portions of bones surrounding the nasal cavity  Functions of paranasal sinuses  Lighten the skull  Amplify sounds made as we speak © 2018 Pearson Education, Ltd. Figure 5.13a Paranasal sinuses. Frontal sinus Ethmoid sinus Sphenoidal sinus Maxillary sinus (a) Anterior view © 2018 Pearson Education, Ltd. Figure 5.13b Paranasal sinuses. Frontal sinus Ethmoid sinus Sphenoid al sinus Maxillary sinus (b) Medial view © 2018 Pearson Education, Ltd.  Skull  Hyoid bone  Closely related to mandible and temporal bones  The only bone that does not articulate with another bone  Serves as a movable base for the tongue  Aids in swallowing and speech © 2018 Pearson Education, Ltd. Figure 5.14 Anatomical location and structure of the hyoid bone. Greater horn Lesser horn Body © 2018 Pearson Education, Ltd.  Vertebral Column (Spine)  Vertebral column provides axial support  Extends from skull to the pelvis  26 vertebral bones are separated by intervertebral discs  7 cervical vertebrae are in the neck  12 thoracic vertebrae are in the chest region  5 lumbar vertebrae are associated with the lower back  Sacrum (formed by fusion of 5 vertebrae)  Coccyx (formed by fusion of 3–5 vertebrae) © 2018 Pearson Education, Ltd. Figure 5.15 The vertebral column. Anterior Posterior 1st cervical vertebra Cervical curvature (atlas) 2nd cervical (concave) 7 vertebrae, vertebra C1 – C 7 (axis) 1st thoracic vertebra Transverse process Spinous Thoracic curvature process (convex) 12 vertebrae, Intervertebral T1 – T12 disc Intervertebral foramen 1st lumbar vertebra Lumbar curvature (concave) 5 vertebrae, L1 – L5 Sacral curvature (convex) 5 fused vertebrae Coccyx 4 fused vertebrae © 2018 Pearson Education, Ltd.  Vertebral Column (Spine)  Primary curvatures  Spinal curvatures of the thoracic and sacral regions  Present from birth  Form a C-shaped curvature in newborns  Secondary curvatures  Spinal curvatures of the cervical and lumbar regions  Develop after birth  Form an S-shaped curvature in adults © 2018 Pearson Education, Ltd. Figure 5.16 The C-shaped spine typical of a newborn. © 2018 Pearson Education, Ltd.  Vertebral Column (Spine)  Parts of a typical vertebra  Body (centrum)  Vertebral arch  Pedicle  Lamina  Vertebral foramen  Transverse processes  Spinous process  Superior and inferior articular processes © 2018 Pearson Education, Ltd. Figure 5.17 A typical vertebra, superior view. Posterior Lamina Vertebral arch Transverse Spinous process process Superior articular process and facet Pedicle Vertebral foramen Body Anterior © 2018 Pearson Education, Ltd. Figure 5.18a Regional characteristics of vertebrae. (a) ATLAS AND AXIS Transverse Posterior process arch Anterior arch Superior view of atlas (C1) Spinous Transverse process process Facet on superior articular process Dens Body Superior view of axis (C2) © 2018 Pearson Education, Ltd. Figure 5.18b Regional characteristics of vertebrae. (b) TYPICAL CERVICAL VERTEBRAE Facet on superior Spinous articular process process Vertebral foramen Transverse Transverse process foramen Superior view Superior articular Body process Spinous process Transverse process Facet on inferior articular process Right lateral view © 2018 Pearson Education, Ltd. Figure 5.18c Regional characteristics of vertebrae. (c) THORACIC VERTEBRAE Spinous process Transverse Vertebral process foramen Facet Facet on for rib superior articular process Body Superior view Facet on Body superior articular process Facet on transverse process Costal facet Spinous for rib process Right lateral view © 2018 Pearson Education, Ltd. Figure 5.18d Regional characteristics of vertebrae. (d) LUMBAR VERTEBRAE Spinous process Vertebral foramen Transverse process Facet on superior Body articular process Superior view Superior Body articular process Spinous Facet on inferior process articular process Right lateral view © 2018 Pearson Education, Ltd. Figure 5.19 Sacrum and coccyx, posterior view. SuperiorAuricular Ala Sacral articularsurface canal process Body Median Sacrum sacral crest Posterior sacral foramina Sacral Coccyx hiatus © 2018 Pearson Education, Ltd.  Thoracic Cage  Bony thorax, or thoracic cage, protects organs of the thoracic cavity  Consists of three parts 1. Sternum 2. Ribs  True ribs (pairs 1–7)  False ribs (pairs 8–12)  Floating ribs (pairs 11–12) 3. Thoracic vertebrae © 2018 Pearson Education, Ltd. Figure 5.20a The bony thorax (thoracic cage). T1 vertebra Jugular notch Clavicular notch Manubrium Sternal angle Body Xiphisternal Sternum True joint ribs Xiphoid (1–7) process False ribs (8–12) Intercostal spaces L1 Floating vertebra Costal cartilage ribs (11, 12) (a) © 2018 Pearson Education, Ltd. Figure 5.20b The bony thorax (thoracic cage). T2 Jugular T3 notch T4 Sternal angle Heart T9 Xiphisternal joint (b) © 2018 Pearson Education, Ltd.  Appendicular Skeleton  Composed of 126 bones  Limbs (appendages)  Pectoral girdle  Pelvic girdle © 2018 Pearson Education, Ltd. Figure 5.8a The human skeleton. Cranium Skull Facial bones Clavicle Thoracic cage Scapula (ribs and Sternum sternum) Rib Humerus Vertebra Vertebra Radius l Ulna Sacru column m Carpals Phalanges Metacarpals Femur Patella Tibia Fibula Tarsals Metatarsals Phalanges (a) Anterior © 2018 Pearson Education, Ltd. view Figure 5.8b The human skeleton. Cranium Bones of pectoral Clavicle girdle Scapula Sternum Upper Rib limb Humerus Vertebr R a adius Bones of Ulna pelvic Carpals girdle Phalanges Metacarpals Femur Lower Tibia limb Fibula (b) Posterior view © 2018 Pearson Education, Ltd.  Bones of the Shoulder Girdle  Also called pectoral girdle  Composed of two bones that attach the upper limb to the axial skeletal 1. Clavicle 2. Scapula  Light, poorly reinforced girdle  Allows the upper limb a exceptional flexibility © 2018 Pearson Education, Ltd. Figure 5.21a Bones of the shoulder girdle. Acromio- clavicular Clavicle joint Scapula (a) Articulated right shoulder (pectoral) girdle showing the relationship to © 2018 Pearson Education, Ltd. bones of the thorax and sternum Figure 5.21b Bones of the shoulder girdle. Posterior Sternal (medial) end Acromial Anterior (lateral) end Superior view Acromial end Sternal end Anterior Posterior Inferior view (b) Right clavicle, superior and inferior views © 2018 Pearson Education, Ltd. Figure 5.21c Bones of the shoulder girdle. Coracoid process Suprascapular notch Superior Acromion angle Glenoid cavity at lateral angle Spine Medial border Lateral border (c) Right scapula, posterior aspect © 2018 Pearson Education, Ltd. Figure 5.21d Bones of the shoulder girdle. Acromion Suprascapular notch Superior border Coracoid process Superior angle Glenoid cavity Lateral angle Lateral (axillary) Medial border (vertebral) border Inferior angle (d) Right scapula, anterior aspect © 2018 Pearson Education, Ltd.  Bones of the Upper Limbs  Humerus  Forms the arm  Single bone  Proximal end articulation  Head articulates with the glenoid cavity of the scapula  Distal end articulation  Trochlea and capitulum articulate with the bones of the forearm © 2018 Pearson Education, Ltd. Figure 5.22a Bones of the right arm and forearm. Greater Head of tubercle humerus Lesser tubercle Anatomical neck Intertubercular sulcus Deltoid tuberosity Radial fossa Medial epicondyle Coronoid fossa Capitulum Trochlea (a) © 2018 Pearson Education, Ltd. Figure 5.22b Bones of the right arm and forearm. Head of humerus Anatomical neck Surgical neck Radial groove Deltoid tuberosity Medial epicondyle Olecranon fossa Lateral Trochlea epicondyle (b) © 2018 Pearson Education, Ltd.  Bones of the Upper Limbs  The forearm has two bones 1. Ulna—medial bone in anatomical position  Proximal end articulation  Coronoid process and olecranon articulate with the humerus 2. Radius—lateral bone in anatomical position  Proximal end articulation  Head articulates with the capitulum of the humerus © 2018 Pearson Education, Ltd. Figure 5.22c Bones of the right arm and forearm. Trochlear notch Olecranon Head Coronoid process Neck Radial Proximal tuberosity radioulnar joint Radius Ulna Inter- osseous membrane Ulnar Radial Distal styloid styloid process process radioulnar joint (c) © 2018 Pearson Education, Ltd.  Bones of the Upper Limbs  Hand  Carpals—wrist bones  8 bones arranged in two rows of 4 bones in each hand  Metacarpals—palm bones  5 per hand  Phalanges—fingers and thumb  14 phalanges in each hand  In each finger, there are 3 bones  In the thumb, there are only 2 bones © 2018 Pearson Education, Ltd. Figure 5.23 Bones of the right hand, anterior view. Distal Middle Phalanges (fingers) Proximal 4 3 2 Metacarpals 5 (palm) 1 Hamate Trapezium Carpals Pisiform Trapezoid (wrist) Triquetrum Scaphoid Lunate Capitate Ulna Radius © 2018 Pearson Education, Ltd.  Bones of the Pelvic Girdle  Formed by two coxal (ossa coxae) bones  Composed of three pairs of fused bones 1. Ilium 2. Ischium 3. Pubis  Pelvic girdle = two coxal bones, sacrum  Pelvis = two coxal bones, sacrum, coccyx © 2018 Pearson Education, Ltd.  Bones of the Pelvic Girdle  The total weight of the upper body rests on the pelvis  Pelvis protects several organs  Reproductive organs  Urinary bladder  Part of the large intestine © 2018 Pearson Education, Ltd. Figure 5.24a The bony pelvis. Iliac crest Sacroiliac joint llium Coxal bone Sacrum (or hip bone) Pelvic brim Pubis Coccyx Ischial spine Acetabulum Ischium Pubic symphysis Pubic arch (a) © 2018 Pearson Education, Ltd. Figure 5.24b The bony pelvis. Ilium Ala Iliac crest Posterior superior iIiac Anterior superior spine iliac spine Posterior inferior Anterior inferior iIiac spine iliac spine Greater sciatic notch Acetabulum Ischial body Body of pubis Ischial spine Pubis Ischial tuberosity Inferior pubic ramus Ischium Obturator Ischial ramus foramen (b) © 2018 Pearson Education, Ltd.  Bones of the Pelvic Girdle  The female’s pelvis  Inlet is larger and more circular  Shallower, on the whole, and the bones are lighter and thinner  Ilia flare more laterally  Sacrum is shorter and less curved  Ischial spines are shorter and farther apart; thus, the outlet is larger  Pubic arch is more rounded because the angle of the pubic arch is greater © 2018 Pearson Education, Ltd. Figure 5.24c The bony pelvis. False pelvis Inlet of true pelvis Pelvic brim Pubic arch (less than 90º) False pelvis Inlet of true pelvis Pelvic brim Pubic arch (more than 90º) (c) © 2018 Pearson Education, Ltd.  Bones of the Lower Limbs  Femur—thigh bone  The heaviest, strongest bone in the body  Proximal end articulation  Head articulates with the acetabulum of the coxal (hip) bone  Distal end articulation  Lateral and medial condyles articulate with the tibia in the lower leg © 2018 Pearson Education, Ltd. Figure 5.25a Bones of the right thigh and leg. Surgical neck Head Inter- trochanteric line Lesser trochanter Lateral epicondyle Medial epicondyle Patellar surface (a) © 2018 Pearson Education, Ltd. Figure 5.25b Bones of the right thigh and leg. Greater Head trochanter Inter- trochanteric Lesser trochanter crest Gluteal tuberosity Intercondylar fossa Medial Lateral condyle condyle (b) © 2018 Pearson Education, Ltd.  Bones of the Lower Limbs  The lower leg has two bones 1. Tibia—shinbone; larger and medially oriented  Proximal end articulation  Medial and lateral condyles articulate with the femur to form the knee joint  Distal end articulation  Medial malleolus forms the inner part of the ankle 2. Fibula—thin and sticklike; lateral to the tibia  Has no role in forming the knee joint  Distal end articulation  Lateral malleolus forms the outer part of the ankle © 2018 Pearson Education, Ltd. Figure 5.25c Bones of the right thigh and leg. Intercondylar eminence Lateral Medial condyle condyle Head Tibial tuberosity Proximal tibiofibular joint Interosseous membrane Anterior border Fibula Tibia Distal tibiofibular joint Medial Lateral malleolus malleolus (c) © 2018 Pearson Education, Ltd.  Bones of the Lower Limbs  Foot  Tarsals—7 bones  Two largest tarsals are the:  Calcaneus (heel bone)  Talus  Metatarsals—5 bones form the sole of the foot  Phalanges—14 bones form the toes © 2018 Pearson Education, Ltd. Figure 5.26 Bones of the right foot, superior view. Phalanges: Distal Middle Proximal Tarsals: Medial Metatarsals cuneiform Tarsals: Intermediate cuneiform Lateral cuneiform Navicular Cuboid Talus Calcaneus © 2018 Pearson Education, Ltd.  Bones of the Lower Limbs  Arches of the feet  Bones of the foot are arranged to form three strong arches  Two longitudinal  One transverse © 2018 Pearson Education, Ltd. Figure 5.27 Arches of the foot. Medial longitudinal arch Transverse arch Lateral longitudinal arch © 2018 Pearson Education, Ltd.  Joints  Joints are articulations  Occur where two or more bones meet  Functions of joints  Hold bones together securely  Allow for mobility  Two ways joints are classified  Functionally  Structurally © 2018 Pearson Education, Ltd.  Joints  Functional joint classifications  Synarthroses  Immovable joints  Amphiarthroses  Slightly movable joints  Diarthroses  Freely movable joints © 2018 Pearson Education, Ltd.  Joints  Structural joint classifications  Fibrous joints  Generally immovable  Cartilaginous joints  Immovable or slightly movable  Synovial joints  Freely movable © 2018 Pearson Education, Ltd. © 2018 Pearson Education, Ltd.  Joints  Fibrous joints  Bones are united by fibrous tissue  Types  Sutures  Immobile  Syndesmoses  Allow more movement than sutures but still immobile  Found on the distal ends of tibia and fibula  Gomphoses  Immobile  Found where the teeth meet the facial bones © 2018 Pearson Education, Ltd. Figure 5.28a Types of joints. Fibrous joints Fibrous connectiv e tissue (a) Suture © 2018 Pearson Education, Ltd. Figure 5.28b Types of joints. Fibrous joints Tibia Fibula Fibrous connective tissue (b) Syndesmosis © 2018 Pearson Education, Ltd.  Joints  Cartilaginous joints  Bones are connected by fibrocartilage  Types  Synchrondrosis  Immobile  Found in epiphyseal plates of growing long bones  Symphysis  Slightly movable  Found in the pubic symphysis, intervertebral joints © 2018 Pearson Education, Ltd. Figure 5.28c Types of joints. Cartilaginous joints First rib Hyaline cartilage Sternum (c) Synchondrosis © 2018 Pearson Education, Ltd. Figure 5.28d Types of joints. Cartilaginous joints Vertebrae Fibrocartilage (d) Symphysis © 2018 Pearson Education, Ltd. Figure 5.28e Types of joints. Cartilaginous joints Pubis Fibro- cartilage (e) Symphysis © 2018 Pearson Education, Ltd.  Joints  Synovial joints  Articulating bones are separated by a joint cavity  Synovial fluid is found in the joint cavity  Four distinguishing features of synovial joints 1. Articular cartilage 2. Articular capsule 3. Joint cavity 4. Reinforcing ligaments © 2018 Pearson Education, Ltd. Figure 5.28f Types of joints. Synovial joints Scapula Articular capsule Articular (hyaline) cartilage Humerus (f) Multiaxial joint (shoulder joint) © 2018 Pearson Education, Ltd. Figure 5.28g Types of joints. Synovial joints Humerus Articular (hyaline) cartilage Articular capsule Radius Ulna (g) Uniaxial joint (elbow joint) © 2018 Pearson Education, Ltd. Figure 5.28h Types of joints. Synovial joints Ulna Radius Articular capsule Carpals (h) Biaxial joint (intercarpal joints of hand) © 2018 Pearson Education, Ltd.  Joints  Synovial joints (continued)  Bursae—flattened fibrous sacs  Lined with synovial membranes  Filled with synovial fluid  Not actually part of the joint  Tendon sheath  Elongated bursa that wraps around a tendon © 2018 Pearson Education, Ltd.  Joints  Types of synovial joints based on shape  Plane joint  Hinge joint  Pivot joint  Condylar joint  Saddle joint  Ball-and-socket joint © 2018 Pearson Education, Ltd. Figure 5.29 General structure of a synovial joint. Acromion of scapula Ligament Joint cavity containing Bursa synovial fluid Ligament Articular (hyaline) Tendon cartilage sheath Synovial membrane Tendon of Fibrous layer of the biceps muscle articular capsule Humerus © 2018 Pearson Education, Ltd. Figure 5.30a Types of synovial joints. Nonaxial Uniaxial Biaxial Multiaxial (f) (a) Plane joint (b) (c) (a) (e) (d) © 2018 Pearson Education, Ltd. Figure 5.30b Types of synovial joints. Nonaxial Uniaxial Biaxial Multiaxial (f) (b) Humerus (c) Ulna (a) (e) (b) Hinge joint (d) © 2018 Pearson Education, Ltd. Figure 5.30c Types of synovial joints. Nonaxial Uniaxial Ulna Biaxial Radius Multiaxial (f) (c) Pivot joint (b) (c) (a) (e) (d) © 2018 Pearson Education, Ltd. Figure 5.30d Types of synovial joints. Nonaxial Uniaxial Biaxial Multiaxial (f) Metacarpal (b) Phalanx (c) (d) Condylar joint (a) (e) (d) © 2018 Pearson Education, Ltd. Figure 5.30e Types of synovial joints. Nonaxial Carpal Uniaxial Metacarpal #1 Biaxial Multiaxial (f) (e) Saddle joint (b) (c) (a) (e) (d) © 2018 Pearson Education, Ltd. Figure 5.30f Types of synovial joints. Nonaxial Uniaxial Biaxial Multiaxial (f) Head of humerus (b) (c) Scapula (f) Ball-and-socket joint (a) (e) (d) © 2018 Pearson Education, Ltd.  Developmental Aspects of the Skeleton  Birth to adulthood  First “long bones” of a fetus are hyaline cartilage  Earliest “flat bones” of the fetal skull are fibrous membranes  As fetus grows, all bone models are converted to bone © 2018 Pearson Education, Ltd. Figure 5.31 Ossification centers in the skeleton of a 12-week-old fetus are indicated by the darker areas. Parietal bone Frontal bone of skull Occipital bone Mandible Clavicle Scapula Radius Ulna Humerus Femur Tibia Ribs Vertebra Hip bone © 2018 Pearson Education, Ltd.  Developmental Aspects of the Skeleton  Fetal skull  Fontanels are fibrous membranes connecting the cranial bones  Known as “soft spots”  Allow skull compression during birth  Allow the brain to grow during later pregnancy and infancy  Usually ossify by 2 years of age © 2018 Pearson Education, Ltd. Figure 5.32a The fetal skull. Anterior fontanel Frontal bone Parietal bone Posterior fontanel Occipital (a) bone © 2018 Pearson Education, Ltd. Figure 5.32b The fetal skull. Anterior fontanel Sphenoidal Parietal bone fontanel Frontal Posterior bone fontanel Occipital bone Mastoid fontanel Temporal bone (b) © 2018 Pearson Education, Ltd.  Developmental Aspects of the Skeleton  Growth of cranium after birth is related to brain growth  Increase in size of the facial skeleton follows tooth development and enlargement of the respiratory passageways © 2018 Pearson Education, Ltd.  Developmental Aspects of the Skeleton  Size of cranium in relationship to body  2 years old—skull is three-fourths the size of adult skull  8 or 9 years old—skull is near adult in size and proportion  Between ages 6 and 11, the face grows out from the skull © 2018 Pearson Education, Ltd.  Developmental Aspects of the Skeleton  Skeletal changes  At birth, the head and trunk are proportionately much longer than the lower limbs  During puberty:  Female pelvis broadens  Entire male skeleton becomes more robust  By the end of adolescence:  Epiphyseal plates become fully ossified © 2018 Pearson Education, Ltd. Figure 5.33a Differences in the growth rates for some parts of the body compared to others determine body proportions. Human newborn Human adult (a) © 2018 Pearson Education, Ltd. Figure 5.33b Differences in the growth rates for some parts of the body compared to others determine body proportions. Newborn 2 yrs. 5 yrs. 15 yrs. Adult (b) © 2018 Pearson Education, Ltd.  Developmental Aspects of the Skeleton  Older adults  Osteoporosis  Bone-thinning disease afflicting:  50 percent of women over age 65  20 percent of men over age 70  Disease makes bones fragile, and bones can easily fracture  Vertebral collapse results in kyphosis (also known as “dowager’s hump”)  Estrogen aids in health and normal density of a female skeleton © 2018 Pearson Education, Ltd. Figure 5.34 Osteoporosis. © 2018 Pearson Education, Ltd. Figure 5.35 Vertebral collapse due to osteoporosis. Age 40 Age 60 Age 70 © 2018 Pearson Education, Ltd.