Y khoa - Dược - Chapter 24: The skeletal system

24The Skeletal SystemLearning Outcomes (cont.)24.1 Describe the structure of bone tissue. 24.2 Explain the functions of bones. 24.3 Compare intramembranous and endochondral ossification.24.4 Describe the skeletal structures and one location of each structure. Learning Outcomes (cont.)24.5 Locate the bones of the skull. 24.6 Locate the bones of the spinal column.24.7 Locate the bones of the rib cage.24.8 Locate the bones of the shoulders, arms, and hands.Learning Outcomes (cont.)24.9 Locate the bones of the hips, legs, and feet.24.10 Describe the three major types of joints and give examples of each. 24.11 Describe the common diseases and disorders of the skeletal system.Introduction Bones provide structure and support206 bones plus joints and connective tissueDivisionsAxial ~ 80 bonesSkullVertebral columnRib cageAppendicular ~ 126 bonesArms and legsPectoral girdlePelvic girdleBone StructureBones contain various kinds of tissuesOsseous tissueBlood vesselsNervesOsseous tissue can appear compact or spongyCompact BoneSpongy (Cancellous)BoneBone Structure (cont.)Structures within compact boneOsteons Bone matrixLamellaLacunaeCanaliculi All bones are made up of both compact and spongy bone Bone Structure (cont.)Long bones Femur and humerus Parts DiaphysisEpiphysisArticular cartilageMedullary cavityPeriosteumEndosteumBone Structure (cont.)Short bones Flat bonesIrregular bonesSesamoid bonesGender Differences in Skeletal StructureMale SkullLarger and heavierForehead shorterFace less roundJaw larger Male pelvisBones are heavier and thickerCavity is narrowerMatching: Holes in the matrix that contain  osteocytes Made of inorganic salts, collagen  fibers, and proteins; between  osteocytes Layers of bone surrounding the canals  of the osteons Elongated cylinders that run the length  of the bone Canals that connect lacunae  to each otherApply Your KnowledgeOsteons Bone matrixLamellaLacunaeCaniculi BDAECANSWER:Very Good!Functions of BonesGive shape to body parts Support and protect soft structures Function in body movementRed bone marrow – hematopoiesisStore calciumApply Your KnowledgeANSWER: Every cell in the body needs calcium, so the body must have a large supply readily available.Why is it important for the bones to store calcium?Bone Growth Ossification Intramembranous ossification Bones begin as tough, fibrous membraneOsteoblasts turn the membrane to boneEndochondral ossification Bones begin as cartilage modelsDiaphysis ~ primary ossification centerDiaphysisBone Growth (cont.)DiaphysisEndochondral ossification Epiphysis ~ secondary ossification centerEpiphyseal disc ~ cartilage between epiphysis and diaphysisBone Growth (cont.)Building Better BonesBone – healthy dietVitamin DCalcium Bone-healthy exercisesWeight-bearingStrength-training Building Better Bones (cont.)Bone-healthy lifestyle – avoid smoking and alcoholBone testsBone density testsBone scanApply Your KnowledgeWhat are the two types of bone growth?ANSWER: Intramembranous ossification, in which bones begin as tough membrane and are turned to bone by osteoblasts, and endochondral ossification, in which primary ossification occurs in the diaphysis of the bone and secondary ossification occurs in the epiphysis.Good Job!Bony Structures Bones are designed with Projections and processes Depressions and hollows at articulationsOpenings for blood vessels and nervesBony Structures (cont.)TermDefinitionCondyleA rounded process that usually articulates with another boneCrestA narrow, ridge-like projectionEpicondyleA projection situated above a condyleForamen An opening through a bone that is usually a passageway for blood vessels, nerves, or ligaments FossaA relatively deep pit or depressionBony Structures (cont.)TermDefinitionHeadAn enlargement on the end of a boneProcessA prominent projection on a bone SutureAn interlocking line of union between bonesTrochanterA relatively large processTubercleA small, knoblike processTuberosityA knoblike process, usually larger than a tubercleApply Your KnowledgeMatch the following:___ Epicondyle A. A relatively deep pit or depression___ Fontanels B. An interlocking line of union between bones___ Fossa C. “Soft spots” felt on an infant’s skull ___ Process D. A knoblike process, usually larger than a  tubercle___ Suture E. A projection situated above a condyle ___ Tuberosity F. A prominent projection on a bone CAFBDEANSWER:GREAT!The SkullTwo bone types – cranial and facialInfant skullsBones not completely formedFontanels – tough membranesSutures The Skull (cont.)Cranial bones FrontalParietalOccipital TemporalExternal auditory meatusSphenoid and ethmoid bonesEar ossicles MalleusIncusStapesClick to see SkullThe Skull (cont.)Facial bonesMandible ~ lower jawMaxillae ~ upper jawZygomatic CheekbonesFused nasal bones form bridge of nosePalatine ~ hard palateVomer ~ divides nasal cavityClick to see SkullThe Skull (cont.)BackParietal boneFrontal boneOccipital boneTemporal boneExternal auditory meatusSphenoid boneZygomatic boneEthmoid boneNasal boneMandibleMaxillaeVomerboneSphenoidboneApply Your KnowledgeMatch the bones of the skull:___ Occipital A. Form the upper jawbone___ Sphenoid B. A thin bone that divides the nasal  cavity___ Mandible C. Part of the floor of the skull ___ Maxillae D. Form the prominence of the cheeks___ Zygomatic E. Back of skull___ Vomer F. Lower jawboneCFADBEANSWER:Very Good!The Spinal Column 7 cervical vertebrae12 thoracic vertebrae 5 lumbar vertebraeSacrumCoccyx The Spinal Column (cont.)Cervical vertebrae Smallest and lightest Located in the neck AtlasAxisThoracic vertebrae Posterior attachment for ribs Lumbar vertebrae Small of the backBear most weightThe Spinal Column (cont.)Sacrum A triangular-shaped bone Five fused vertebraeCoccyx A small, triangular-shaped bone 3 to 5 fused vertebrae Apply Your KnowledgeIdentify the sections of the spinal column and give the number of vertebrae for each.Thoracic – 12Lumbar – 5Sacrum – 5 fusedCoccyx – 3 to 5 fusedCervical – 7ANSWER:Right!The Rib CageSternum BreastplateJoins with the clavicles and most ribsXiphoid processTo ribcageThe Rib Cage (cont.)Ribs All are attached posteriorly to thoracic vertebraeTrue – 1st 7 pairsFalse – pairs 8, 9, and 10Floating – pairs To ribcageThe Rib Cage (cont.)BackApply Your KnowledgeTrue or False:___ The sternum forms the front middle portion of the rib cage.___ The xiphoid process is a boney tip of the sternum.___ The true ribs are the first five pairs of ribs. ___ False ribs attach to the costal cartilage of rib pair seven.___ Floating ribs attach to the xiphoid process.TTANSWER:FcartilaginousFseven Fdo not attach anteriorly to any structure.BRAVO!Bones of the Shoulders, Arms, and HandsShoulders Clavicles ~ collar bonesScapulae ~ shoulder bladeArm bones HumerusRadius Ulna Bones of the Shoulders, Arms, and Hands (cont.)Hand Carpals ~ 8Metacarpals ~ 5Phalanges ~ 14 3 per finger2 per thumbApply Your KnowledgeMatch the following:___ Clavicle A. Pectoral girdle___ Radius B. Arm bones___ Humerus C. Hands___ Carpals___ Scapula___ Ulna___ Phalanges___ MetacarpalsABBBCCCAANSWER:Excellent!Bones of the Hips, Legs, and FeetHip bones Coxal bones IliumIschiumPubis Bones of the Hips, Legs, and Feet (cont.)Bones of leg Femur Patella Tibia Fibula Bones of the Hips, Legs, and Feet (cont.)Bones of the foot Tarsals ~ 7Metatarsals ~ 5 Phalanges ~ 143 per toe2 per each big toeApply Your KnowledgeMatch the following:A. Coxal bones B. Leg bones C. Foot bones___ Tibia ___ Patella ___ Ilium ___ Ischium ___ Femur ___ Metatarsals___ Pubis ___ Fibula___ Calcaneus ___ TarsalsBBBAAACCCBANSWERS:Super!JointsJunctions between bones Fibrous joints Connected together with short fibers Between cranial bones and facial bonesSuturesJoints (cont.)Cartilaginous jointsDisc of cartilage Slightly moveableBetween vertebraeJoints (cont.)Synovial joints Covered with hyaline cartilageFibrous joint capsule Freely movableLigaments hold bones togetherApply Your KnowledgeMatch the following:A. Fibrous joints B. Cartilaginous joints C. Synovial joints____ Between cranial bones and facial bones____ Covered with hyaline cartilage____ Between vertebrae____ Freely movable____ Sutures in the skullABCCAANSWER:Yippee!Common Diseases and Disorders of the Skeletal SystemArthritisOsteoarthritis Degenerative joint disease (DJD)Weight-bearing jointsRheumatoid arthritis Chronic systemic inflammatory disease Smaller joints and surrounding tissuesCommon Diseases and Disorders of the Skeletal System (cont.)Bursitis – inflammation of the bursaEwing sarcoma family of tumors (ESFT) Primarily affect boneUsually lower extremitiesGout – deposits of uric acid crystals in jointsCommon Diseases and Disorders of the Skeletal System (cont.)Kyphosis – humpbackLordosis –swaybackOsteogenesis imperfecta – brittle-bone diseaseOsteoporosis – thin, porous bonesCommon Diseases and Disorders of the Skeletal System (cont.)Osteosarcoma – bone cancer from osteoblastsPaget’s disease – bones enlarge, become deformed, and weakScoliosis – an abnormal S-shaped curvature of the spineApply Your KnowledgeOsteoarthritis is a degenerative joint disease that primarily affects weight-bearing joints.Rheumatoid arthritis chronic systemic inflammatory disease of smaller joints and surrounding tissues; it is thought to be an autoimmune disease.What is the difference between osteoarthritis and rheumatoid arthritis?Nice Work!In Summary24.1 Bones consist of the following substances: osteons or Haversian systems; bone matrix between osteocytes (bone cells); collagen fibers and proteins; the lamella; and canaliculi. The skeleton consists of long bone, short bones, flat bones and irregular bones The diaphysis is the shaft of the long bone. The epiphysis is an end of a long bone. Articular cartilage covers the end of the long bones. The endosteum lines the medullary cavity. The periosteum is the membrane surrounding the diaphysis. In Summary24.2 Bone functions include giving shape to body parts, protecting soft structures of the body, and assisting in movement. The red bone marrow is responsible for hematopoiesis. Bones also store calcium. 24.3 Bones grow through the two types of ossification: intramembranous ossification and endochondral ossification. The cartilage plate between the diaphysis and the epiphysis allows for growth of the long bone. In Summary (cont.)24.4 Skeletal structures include the following: condyles, crests, epicondyles, foramina, fossae, heads, processes, sutures, trochanters, tubercles, and tuberosities. 24.5 The major bones of the skull are the frontal, parietal, temporal, and occipital bones. The skull also contains the fontanels, the mastoid processes, sphenoid,ethmoid, and ear ossicles. The facial bones include the mandible, maxillae, zygomatics, nasal and palatine bones, and the vomer. In Summary (cont.)24.6 The spinal column includes cervical, thoracic, and lumbar vertebrae; the sacrum; and the coccyx. 24.7 There are 12 pairs of ribs, a sternum, and the xiphoid process.24.8 Each upper extremity includes the clavicle, scapula, humerus, radius, ulna, carpals, metacarpals, and phalanges..In Summary (cont.)24.9 The bones of the hip, leg, and foot include the coxal bones, the femur, patella, tibia, fibula, metatarsals, tarsals, and phalanges.24.10 The three joint types are fibrous joints, cartilaginous joints, and synovial joints. A synovial joint consists of hyaline-covered bones held together by a fibrous joint capsule, which is lined by a synovial membrane that secretes synovial fluid. Ligaments hold the bones of these joints together.In Summary (cont.)24.11 There are many common diseases and disorders of the bones and the skeletal system with varied signs, symptoms, and treatments. Examples include arthritis, bursitis, EFT, gout, kyphosis, lordosis, and scoliosis, as well as osteoporosis and osteosarcoma.. Rigid, the skeleton of habit alone upholds the human frame.~ Virginia WoolfEnd of Chapter 24