© 2012 pearson education, inc. the skeletal system parts of the skeletal system bones (skeleton)...

Download © 2012 Pearson Education, Inc. The Skeletal System Parts of the skeletal system Bones (skeleton) Joints Cartilages Ligaments Two subdivisions of the skeleton

Post on 27-Dec-2015




0 download

Embed Size (px)


Nerve activates contraction

The Skeletal System Parts of the skeletal systemBones (skeleton)JointsCartilagesLigamentsTwo subdivisions of the skeletonAxial skeletonAppendicular skeletonhttp://www.youtube.com/watch?v=8d-RBe8JBVs

2012 Pearson Education, Inc.Functions of BonesSupport the bodyProtect soft organsSkull and vertebrae for brain and spinal cordRib cage for thoracic cavity organsAllow movement due to attached skeletal musclesStore minerals and fatsCalcium and phosphorusFat in the internal marrow cavityBlood cell formation (hematopoiesis) 2012 Pearson Education, Inc.Bones of the Human BodyThe adult skeleton has 206 bonesTwo basic types of bone tissue1. Compact bone2. Spongy boneSmall needle-like pieces of boneMany open spaces

2012 Pearson Education, Inc.Classification of Bones on the Basis of ShapeBones are classified as:LongShortFlatIrregular

2012 Pearson Education, Inc.Classification of BonesLong bonesTypically longer than they are wideShaft with heads situated at both endsContain mostly compact boneAll of the bones of the limbs (except wrist, ankle, and bones)Example:FemurHumerus

2012 Pearson Education, Inc.Classification of BonesShort bonesGenerally cube-shapedContain mostly spongy boneIncludes bones of the wrist and ankleSesamoid bones are a type of short bone which form within tendons (patella)Example:CarpalsTarsals

2012 Pearson Education, Inc.Classification of BonesFlat bonesThin, flattened, and usually curvedTwo thin layers of compact bone surround a layer of spongy boneExample: SkullRibsSternum

2012 Pearson Education, Inc.

Classification of BonesIrregular bonesIrregular shapeDo not fit into other bone classification categoriesExample:Vertebrae Hip bones 2012 Pearson Education, Inc.Anatomy of a Long BoneDiaphysisShaftComposed of compact boneEpiphysis Ends of the boneComposed mostly of spongy boneFigure 5.3a

DistalepiphysisDiaphysisProximalepiphysisArticularcartilageSpongy boneEpiphyseallinePeriosteumCompact boneMedullarycavity (linedby endosteum)(a)http://www.youtube.com/watch?v=owlpf6zHgyw

2012 Pearson Education, Inc.Anatomy of a Long BonePeriosteumOutside covering of the diaphysisFibrous connective tissue membranePerforating (Sharpeys) fibersSecure periosteum to underlying boneArteriesSupply bone cells with nutrients


2012 Pearson Education, Inc.Figure 5.3c

Yellowbone marrowCompact bonePerforating(Sharpeys)fibersNutrientarteriesPeriosteumEndosteum(c) 2012 Pearson Education, Inc.Figure 5.3b

Compact boneSpongy boneArticularcartilage(b)Anatomy of a Long BoneArticular cartilageCovers the external surface of the epiphysesMade of cartilageDecreases friction at joint surfaces 2012 Pearson Education, Inc.Figure 5.3a

DistalepiphysisDiaphysisProximalepiphysisArticularcartilageSpongy boneEpiphyseallinePeriosteumCompact boneMedullarycavity (linedby endosteum)(a)Epiphyseal plateFlat plate of hyaline cartilage seen in young, growing boneEpiphyseal lineRemnant of the epiphyseal plateSeen in adult bonesAnatomy of a Long Bone 2012 Pearson Education, Inc.Anatomy of a Long BoneMarrow (medullary) cavity Cavity inside of the shaftContains yellow marrow (mostly fat) in adultsContains red marrow for blood cell formation in infantsIn adults, red marrow is situated in cavities of spongy bone and epiphyses of some long bones 2012 Pearson Education, Inc.Bone MarkingsSurface features of bonesSites of attachments for muscles, tendons, and ligamentsPassages for nerves and blood vesselsCategories of bone markingsProjections or processesgrow out from the bone surfaceTerms often begin with TDepressions or cavitiesindentationsTerms often begin with F 2012 Pearson Education, Inc.Microscopic Anatomy of Compact BoneOsteon (Haversian system)A unit of bone containing central canal and matrix ringsCentral (Haversian) canalOpening in the center of an osteonCarries blood vessels and nervesPerforating (Volkmanns) canalCanal perpendicular to the central canalCarries blood vessels and nerves 2012 Pearson Education, Inc.Figure 5.4a

CompactbonePeriostealblood vesselPeriosteumPerforatingfibersCentral (Haversian) canalPerforating(Volkmanns) canalBlood vesselSpongy boneBlood vessel continues intomedullary cavity containing marrowLamellae(a)Osteon(Haversian system) 2012 Pearson Education, Inc.Microscopic Anatomy of BoneLacunaeCavities containing bone cells (osteocytes)Arranged in concentric rings called lamellaeLamellaeRings around the central canalSites of lacunaehttp://www.youtube.com/watch?v=cNdwwVCpld8&feature=relmfu

2012 Pearson Education, Inc.Figure 5.4b

LamellaCanaliculusLacunaCentral (Haversian) canal(b)Osteocyte 2012 Pearson Education, Inc.Figure 5.4c

OsteonLacunaCentralcanalInterstitiallamellae(c) 2012 Pearson Education, Inc.Microscopic Anatomy of BoneCanaliculi Tiny canalsRadiate from the central canal to lacunaeForm a transport system connecting all bone cells to a nutrient supplyhttp://www.youtube.com/watch?v=CQhUINnTdZI&feature=relmfu

2012 Pearson Education, Inc.Figure 5.4b

LamellaCanaliculusLacunaCentral (Haversian) canal(b)Osteocytehttp://www.youtube.com/watch?v=ylmanEGjRuY&feature=relmfu

2012 Pearson Education, Inc.Formation of the Human SkeletonIn embryos, the skeleton is primarily hyaline cartilageDuring development, much of this cartilage is replaced by bone called ossificationCartilage remains in isolated areasBridge of the noseParts of ribsJoints 2012 Pearson Education, Inc.Bone Growth (Ossification)Epiphyseal plates allow for lengthwise growth of long bones during childhoodNew cartilage is continuously formedOlder cartilage becomes ossifiedCartilage is broken downEnclosed cartilage is digested away, opening up a medullary cavityBone replaces cartilage through the action of osteoblasts 2012 Pearson Education, Inc.Bone Growth (Ossification)Bones are remodeled and lengthened until growth stopsBones are remodeled in response to two factorsBlood calcium levelsPull of gravity and muscles on the skeletonBones grow in width (called appositional growth) 2012 Pearson Education, Inc.Figure 5.5

In a fetusIn an embryoBone collarHyalinecartilagemodelBone startingto replacecartilageIn a childMedullarycavityNew center ofbone growthHyalinecartilageEpiphysealplate cartilageGrowthin bonelengthNew boneformingInvadingbloodvesselsEpiphysealplatecartilageArticularcartilageSpongyboneNew boneformingGrowthin bonewidthhttp://www.youtube.com/watch?v=t5_3sNLtfxQ

2012 Pearson Education, Inc.Types of Bone CellsOsteocytesmature bone cellsOsteoblastsbone-forming cellsOsteoclastsgiant bone-destroying cellsBreak down bone matrix for remodeling and release of calcium in response to parathyroid hormoneBone remodeling is performed by both osteoblasts and osteoclasts 2012 Pearson Education, Inc.Bone FracturesFracturebreak in a boneTypes of bone fracturesClosed (simple) fracturebreak that does not penetrate the skinOpen (compound) fracturebroken bone penetrates through the skinBone fractures are treated by reduction and immobilization 2012 Pearson Education, Inc.Common Types of FracturesComminutedbone breaks into many fragmentsCompressionbone is crushedDepressedbroken bone portion is pressed inwardImpactedbroken bone ends are forced into each otherSpiralragged break occurs when excessive twisting forces are applied to a boneGreenstickbone breaks incompletelyhttp://www.youtube.com/watch?v=c5Q5GPwAS4k

Setting a bone: http://www.youtube.com/watch?v=nQVihuOUQkU&feature=related

2012 Pearson Education, Inc.

Comminuted fracture

Compression fracture 2012 Pearson Education, Inc.Depressed fractureImpacted fracture

2012 Pearson Education, Inc.Spiral fractureGreenstick fracture

2012 Pearson Education, Inc.Figure 5.7

Internalcallus(fibroustissue andcartilage) Hematomaforms. Fibrocartilage callus forms. Bony callus forms. Bone remodeling occurs.1234HematomaBonycallus ofspongyboneSpongybonetrabeculaNewbloodvesselsExternalcallusHealedfractureHealing of bone fractures 2012 Pearson Education, Inc.The Axial SkeletonForms the longitudinal axis of the bodyDivided into three partsSkullVertebral columnBony thorax 2012 Pearson Education, Inc.Figure 5.8a

(a) Anterior viewPhalangesMetatarsalsTarsalsFibulaTibiaPatellaFemurMetacarpalsPhalangesCarpalsUlnaRadiusVertebraHumerusRibSternumScapulaClavicleFacial bonesCraniumSkullThoracic cage(ribs andsternum)VertebralcolumnSacrum 2012 Pearson Education, Inc.Figure 5.8b

(b) Posterior viewFibulaTibiaFemurMetacarpalsPhalangesCarpalsRadiusUlnaVertebraHumerusRibScapulaClavicleCraniumBones ofpectoralgirdleUpperlimbBones ofpelvicgirdleLowerlimb 2012 Pearson Education, Inc.The SkullTwo sets of bonesCraniumFacial bonesBones are joined by suturesOnly the mandible is attached by a freely movable joint 2012 Pearson Education, Inc.Figure 5.9

Coronal sutureParietal boneLambdoidsutureTemporal boneSquamous sutureOccipital boneZygomatic processExternal acoustic meatusMastoid processStyloid processMandibular ramusFrontal boneSphenoid boneEthmoid boneLacrimal boneNasal boneZygomatic boneMaxillaAlveolarprocessesMandible (body)Mental foramen 2012 Pearson Education, Inc.Figure 5.10

SphenoidboneTemporal boneInternalacoustic meatusParietal boneOccipital boneForamen magnumJugular foramenForamen ovaleSella turcicaOptic canalFrontal boneCribriform plateCrista galliEthmoidbone 2012 Pearson Education, Inc.

Figure 5.12Coronal sutureParietal boneNasal boneSphenoid boneEthmoid boneLacrimal boneZygomatic boneMaxillaMandibleAlveolar processesVomerInferior nasal conchaMiddle nasal conchaof ethmoid boneTemporal boneOptic canalSuperior orbital fissureFrontal bone 2012 Pearson Education, Inc.Paranasal SinusesHollow portions of bones surrounding the nasal cavityFunctions of paranasal


View more >