Osseous Tissue & Skeletal Structure Introduction Classification of Bones Bone Histology Bone...
-
Upload
lambert-clark -
Category
Documents
-
view
226 -
download
0
Transcript of Osseous Tissue & Skeletal Structure Introduction Classification of Bones Bone Histology Bone...
Osseous Tissue & Skeletal Osseous Tissue & Skeletal StructureStructure
IntroductionIntroduction Classification of BonesClassification of Bones Bone HistologyBone Histology Bone Development & GrowthBone Development & Growth The Dynamic Nature of BoneThe Dynamic Nature of Bone Surface Features of BoneSurface Features of Bone
IntroductionIntroduction
• StructuresStructures:: Bones & supporting tissuesBones & supporting tissues
• Functions of the Skeletal SystemFunctions of the Skeletal System:: Anatomically-related functionsAnatomically-related functions Physiologically-related functionsPhysiologically-related functions
Bones of the Human BodyBones of the Human Body
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 1-3/4 minASF Video plays about 1-3/4 min
Learning ObjectivesLearning Objectives
• SkeletalSkeletal ElementsElements:: List general elements of the skeletonList general elements of the skeleton
• SkeletalSkeletal FunctionFunction:: Describe the functions of the skeletal Describe the functions of the skeletal
systemsystem
General General Skeletal ElementsSkeletal Elements
• BonesBones• LigamentsLigaments• CartilageCartilage• Membranes & Membranes &
specialized tissues specialized tissues associated with jointsassociated with joints
Functions of the Skeletal SFunctions of the Skeletal Systemystem
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 5 minASF Video plays about 5 min
Skeletal System FunctionsSkeletal System Functions
• SupportSupport – bones provide the structural – bones provide the structural frameworkframework for attachment of soft tissues for attachment of soft tissues & organs& organs
• ProtectionProtection – bones – bones encaseencase many vital many vital organsorgans brain, spinal cord, & special sense organsbrain, spinal cord, & special sense organs cardio-pulmonary organscardio-pulmonary organs digestive organs & urinary organsdigestive organs & urinary organs female reproductive organsfemale reproductive organs
Functions of Bone: SupporFunctions of Bone: Supportt
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 50 secASF Video plays about 50 sec
Functions of Bone: ProtectiFunctions of Bone: Protectionon
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 1-3/4 minASF Video plays about 1-3/4 min
Skeletal System FunctionsSkeletal System Functions
• HemopoiesisHemopoiesis – stem cells in – stem cells in red bonered bone marrow produce marrow produce RBCsRBCs, , plateletsplatelets, & , & WBCsWBCs
• LeverageLeverage – bones change magnitude – bones change magnitude & direction of forces generated by & direction of forces generated by skeletal muscles to allow skeletal muscles to allow movementmovement
Functions of Bone: Blood PFunctions of Bone: Blood Productionroduction
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 53 secASF Video plays about 53 sec
Functions of Bone: MovemFunctions of Bone: Movementent
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 1-1/4 minASF Video plays about 1-1/4 min
Skeletal System FunctionsSkeletal System Functions
• StorageStorage yellow bone marrowyellow bone marrow of long bone of long bone
cavities: lipid reservescavities: lipid reserves mineralsminerals: : CaCa2+2+ & & POPO44
3-3- ions ions
ClassificationClassificationOf Bones & Bone TissueOf Bones & Bone Tissue
• Classification:Classification: Bones may be classified on the basis Bones may be classified on the basis
of shapeof shape
• Osseous Tissue:Osseous Tissue: Compact bone (lamellar bone)Compact bone (lamellar bone) Spongy bone (cancellous bone)Spongy bone (cancellous bone)
• Specific Bone TerminologySpecific Bone Terminology
Learning ObjectivesLearning Objectives
• BoneBone ClassificationClassification:: Classify bones according to their Classify bones according to their
shapes & provide an example of each shapes & provide an example of each typetype
• BoneBone TissuesTissues:: Identify 2 types of bone tissueIdentify 2 types of bone tissue
• LongLong && FlatFlat BoneBone TerminologyTerminology:: Identify the regions of a typical long Identify the regions of a typical long
bone & flat bonebone & flat bone
Bone ClassificationBone Classification
• LongLong bones bones long & slenderlong & slender arms & legs; hands & feet; arms & legs; hands & feet;
fingers & toes (appendages)fingers & toes (appendages)
Ex:Ex: femurfemur
• ShortShort bones bones boxlikeboxlike wrists & ankleswrists & ankles
Ex:Ex: talustalus
Bone ClassificationBone Classification
• FlatFlat bones bones thin w/ parallel surfacesthin w/ parallel surfaces superior & lateral cranium; superior & lateral cranium;
shoulder blades; rib cage; hip bonesshoulder blades; rib cage; hip bones
Ex:Ex: sternumsternum
• IrregularIrregular bones bones complex shapecomplex shape inferior cranium; vertebrae; inferior cranium; vertebrae;
facial bonesfacial bones
Ex:Ex: mandiblemandible
Bone ClassificationBone Classification
• SesamoidSesamoid bones bones small, flat; develop w/in tendonssmall, flat; develop w/in tendons knee cap; bones at “big” toe jointsknee cap; bones at “big” toe joints
Ex:Ex: patellapatella
• SuturalSutural bones bones (a.k.a., W(a.k.a., WÖÖrmian bones)rmian bones) small, flat, irregularsmall, flat, irregular develop w/in sutures of cranial bonesdevelop w/in sutures of cranial bones
No ExampleNo Example
Bone TerminologyBone Terminology
• Long bones:Long bones: epiphysesepiphyses (proximal & distal)(proximal & distal)
cortexcortex – compact bone – compact bonemedullary regionmedullary region – spongy bone – spongy bone
contains red marrowcontains red marrow
metaphyses metaphyses (proximal & distal)(proximal & distal)
diaphysis diaphysis – compact bone (cortex)– compact bone (cortex) marrow cavitymarrow cavity – – yellow marrowyellow marrow w/in w/in
diaphysis (medullary)diaphysis (medullary)
Blood SupplyBlood Supply
• Nutrient artery & veinNutrient artery & vein supply supply diaphysisdiaphysis
• Metaphyseal vesselsMetaphyseal vessels supply diaphyseal surface of supply diaphyseal surface of
epiphyseal plateepiphyseal plate• Periosteal vesselsPeriosteal vessels
supply supply osteonsosteons of outer compact bone of outer compact bone w/ branches into w/ branches into spongy bone of spongy bone of epiphysesepiphyses
Bone TerminologyBone Terminology
• Flat bones:Flat bones: external tableexternal table – – compact bonecompact bone
diploëdiploë – – spongy bonespongy bonecontains red marrowcontains red marrow
internal tableinternal table – – compact bonecompact bone
Structure of BoneStructure of Bone
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 1-3/4 minASF Video plays about 1-3/4 min
Bone Tissue TypesBone Tissue Types
• Compact BoneCompact Bone Dense boneDense bone
• Spongy BoneSpongy Bone Open network of struts & platesOpen network of struts & plates
Compact Bone:Compact Bone:Structure & FunctionStructure & Function
• Structure: Structure: Lamellar BoneLamellar Bone OsteonOsteon
central (osteonic) canal w/ blood vesselscentral (osteonic) canal w/ blood vesselsosteocytes in osteocytes in lacunaelacunae form concentric form concentric
layers – layers – concentric lamellaeconcentric lamellaecanaliculicanaliculi – interconnect lacunae – interconnect lacunae
Perforating canalsPerforating canals – between – between osteonsosteons
Compact Bone:Compact Bone:Structure & FunctionStructure & Function
Interstitial lamellaeInterstitial lamellae – between – between circular osteonscircular osteons
Circumferential lamellaeCircumferential lamellae – outer – outer perimeter of boneperimeter of bone
• Function: Function: Lamellar BoneLamellar Bone strength along longitudinal axis of strength along longitudinal axis of
bonebone resist compressionresist compression
Spongy Bone:Spongy Bone:Structure & FunctionStructure & Function
• Structure: Structure: Cancellous BoneCancellous Bone trabeculaetrabeculae – struts & plates w/ large – struts & plates w/ large
spacesspaces no blood vessels; diffusion through no blood vessels; diffusion through
canaliculi of surrounding compact canaliculi of surrounding compact bone bone
Spongy Bone:Spongy Bone:Structure & FunctionStructure & Function
• Function: Function: Cancellous BoneCancellous Bone strength from multiple directionsstrength from multiple directions lightens bone to ease movementlightens bone to ease movement supports & protects stem cells forming supports & protects stem cells forming
red bone marrowred bone marrow
Bone MembranesBone Membranes
• PeriosteumPeriosteum locuslocus – surrounds bone – surrounds bone functionsfunctions::
provides route for blood vessels & nervesprovides route for blood vessels & nervesisolates bone from surrounding tissueisolates bone from surrounding tissueparticipates in bone growth & repairparticipates in bone growth & repair
Periosteum StructurePeriosteum Structure
• PeriosteumPeriosteum (cont)(cont) 2 layers:2 layers:
outer outer fibrousfibrous layer layercollagen fiberscollagen fiberscontinuous w/ ligaments & tendonscontinuous w/ ligaments & tendons
inner inner cellularcellular layer layerosteoblastsosteoblastsproduce produce perforating fibersperforating fibers (Sharpey’s (Sharpey’s
fibers) that penetrate bone matrixfibers) that penetrate bone matrixosteogenicosteogenic potentialpotential – can participate – can participate
in bone remodelingin bone remodeling
Bone MembranesBone Membranes
• EndosteumEndosteum locuslocus – lines marrow cavities of bones – lines marrow cavities of bones functionfunction: : osteogenic layerosteogenic layer
osteoclastsosteoclasts osteolysisosteolysisosteoblastsosteoblasts osteogenesisosteogenesis
Bone HistologyBone Histology
• Bone Tissue OrganizationBone Tissue Organization• Bone MatrixBone Matrix• Bone CellsBone Cells• Compact & Spongy BoneCompact & Spongy Bone• Periosteum & EndosteumPeriosteum & Endosteum
Learning ObjectivesLearning Objectives
• BoneBone TissueTissue:: Identify 4 features of a representative Identify 4 features of a representative
sample of bone tissuesample of bone tissue
• BoneBone MatrixMatrix:: Identify the components of the bone Identify the components of the bone
matrixmatrix
Learning ObjectivesLearning Objectives
• BoneBone CellsCells:: Identify 4 types of bone cells & Identify 4 types of bone cells &
describe the locations & functions of describe the locations & functions of eacheach
• CompactCompact && SpongySpongy BoneBone:: Compare the structures & functions of Compare the structures & functions of
compact & spongy bonecompact & spongy bone
Bone Tissue:Bone Tissue:Connective TissueConnective Tissue
• MatrixMatrix protein fibers – collagenprotein fibers – collagen ground substance – calcium saltsground substance – calcium salts
• LacunaeLacunae – pockets in matrix containing – pockets in matrix containing mature bone cellsmature bone cells
• CanaliculiCanaliculi – narrow passageways – narrow passageways through matrix that connect lacunaethrough matrix that connect lacunae
• Connective tissue Connective tissue membranesmembranes - - surround bones & line inner cavitiessurround bones & line inner cavities
canaliculicanaliculicentral canal of osteoncentral canal of osteon
matrixmatrix
osteocyte in lacunaosteocyte in lacuna
Bone MatrixBone Matrix
• Protein component (Protein component (osteoidosteoid)) collagencollagen fibers – fibers – 1/3 wt.1/3 wt.
• Mineral component:Mineral component: hydroxyapatitehydroxyapatite crystals: crystals:
CaCa1010(PO(PO44))66(OH)(OH)2 2 – – 2/3 wt.2/3 wt. CaCa33(PO(PO44))22
Ca(OH)Ca(OH)22
imbedded w/in hydroxyapatite crytals imbedded w/in hydroxyapatite crytals – – CaCOCaCO33 , Na, K, Mg, F, Na, K, Mg, F
form crystal latticeform crystal lattice
Bone CellsBone Cells
• OsteoprogenitorOsteoprogenitor cells cells stem (mesenchymal) cellsstem (mesenchymal) cells locuslocus – external & internal membranes of – external & internal membranes of
bonesbones functionfunction – form osteoblasts to repair bone – form osteoblasts to repair bone
• OsteoblastsOsteoblasts locuslocus – external & internal membranes of – external & internal membranes of
bonesbones functionfunction – – osteogenesisosteogenesis: produce new bone : produce new bone
matrix (matrix (osteoidosteoid))
Bone CellsBone Cells
• OsteocytesOsteocytes locuslocus – – lacunaelacunae w/in mature bone matrix w/in mature bone matrix functionsfunctions::
recycle Carecycle Ca2+2+ salts in surrounding matrix salts in surrounding matrix convert to osteoblasts to repair damaged boneconvert to osteoblasts to repair damaged bone
• OsteoclastsOsteoclasts locuslocus – external & internal membranes of – external & internal membranes of
bonesbones giant cells w/ 50+ nuclei derived from giant cells w/ 50+ nuclei derived from
monocytesmonocytes functionfunction – – osteolysisosteolysis: break down bone : break down bone
matrixmatrix
Bone Bone Formation & GrowthFormation & Growth
• Calcification -v- OssificationCalcification -v- Ossification• Intramembranous OssificationIntramembranous Ossification• Endochondral OssificationEndochondral Ossification• Blood & Nerve SupplyBlood & Nerve Supply
Learning ObjectivesLearning Objectives
• OssificationOssification:: Compare the mechanisms of Compare the mechanisms of
intramembranous & endochondral intramembranous & endochondral ossificationossification
• DevelopmentDevelopment:: Discuss the timing of bone Discuss the timing of bone
development & growth & account for development & growth & account for differences in the internal structure of differences in the internal structure of adult bonesadult bones
Bone DevelopmentBone Development
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 1-1/4 minASF Video plays about 1-1/4 min
Ossification -v- Ossification -v- CalcificationCalcification
• OssificationOssification Process by which other Process by which other tissues are tissues are
replaced by bonereplaced by bone• CalcificationCalcification
Process of Process of calcium depositioncalcium depositionoccurs during occurs during ossificationossification (bone (bone
formation)formation)may also occur in other, may also occur in other, non-bonynon-bony
tissuestissues
Intramembranous Intramembranous OssificationOssification
• Dermal ossificationDermal ossification osteoblasts differentiate w/in osteoblasts differentiate w/in
mesenchymal or fibrous connective mesenchymal or fibrous connective tissuetissue
occurs in deep layers of the dermisoccurs in deep layers of the dermis resulting bones called “resulting bones called “dermaldermal bonesbones””
Dermal BonesDermal Bones
• Minority of bones of the bodyMinority of bones of the body Roofing bones of the Roofing bones of the CraniumCranium
parietalsparietalsfrontalfrontaloccipitaloccipital
MandibleMandible ClaviclesClavicles Sesamoid bonesSesamoid bones
patellapatella
Endochondral OssificationEndochondral Ossification
• Ossification of hyaline cartilage Ossification of hyaline cartilage modelmodel chondrocyteschondrocytes produce produce cartilagecartilage; then ; then
die as nutrients are cut off by matrix; die as nutrients are cut off by matrix; spaces through the matrix are createdspaces through the matrix are created
blood vessels grow into spaces in the blood vessels grow into spaces in the cartilagecartilage
osteoblasts differentiate and lay down osteoblasts differentiate and lay down bone matrixbone matrix
Endochondral BonesEndochondral Bones
• Most of the bones in the bodyMost of the bones in the body Basal bones of the Basal bones of the CraniumCranium
sphenoid & ethmoidsphenoid & ethmoidtemporaltemporal
Facial bonesFacial bonesmaxillaries & nasalsmaxillaries & nasalszygomatics, palatines, etczygomatics, palatines, etc
VertebraeVertebrae Bones of the appendagesBones of the appendages
femur, tibia, fibula, tarsals, etcfemur, tibia, fibula, tarsals, etchumerus, radius, ulna, carpals, etchumerus, radius, ulna, carpals, etc
OssificationOssification
EpiphysealEpiphysealPlatePlate
• Increase in bone lengthIncrease in bone length locuslocus of active growth in lengthening of active growth in lengthening
long boneslong bones• Cartilage is converted to bone via Cartilage is converted to bone via
endochondral ossificationendochondral ossification• Under control of hormones:Under control of hormones:
growth hormonegrowth hormone thyroid hormonesthyroid hormones sex hormonessex hormones
Appositional Bone GrowthAppositional Bone Growth
Nervous SupplyNervous Supply
• Sensory neurons penetrate cortex Sensory neurons penetrate cortex w/ nutrient arteryw/ nutrient artery
• Innervate:Innervate: endosteumendosteum marrow cavitymarrow cavity epiphysesepiphyses
• Sensory innervation of bone is Sensory innervation of bone is extensiveextensive
Bone RemodelingBone Remodeling& Homeostasis& Homeostasis
• Effects of ExerciseEffects of Exercise• Hormonal & Nutritional EffectsHormonal & Nutritional Effects• Bone as a Calcium ReserveBone as a Calcium Reserve• Fracture & RepairFracture & Repair• AgingAging
Learning ObjectivesLearning Objectives
• RemodelingRemodeling && HomeostasisHomeostasis:: Describe the remodeling & homeostatic Describe the remodeling & homeostatic
mechanisms of the skeletal systemmechanisms of the skeletal system
• FactorsFactors AffectingAffecting Skeletal SystemSkeletal System DevelopmentDevelopment:: Discuss the effects of nutrition, hormones, Discuss the effects of nutrition, hormones,
exercise, & aging the skeletal systemexercise, & aging the skeletal system
• BoneBone RepairRepair:: Describe the different types of fractures & Describe the different types of fractures &
explain how they healexplain how they heal
Bone RemodelingBone Remodeling
• Recycling:Recycling: Bone Bone organic componentsorganic components – proteins – proteins Bone Bone mineral componentmineral component – – hydroxyapatitehydroxyapatite
• Bone cells:Bone cells: osteocytesosteocytes – continuous remodeling – continuous remodeling osteoclastsosteoclasts & & osteoblastsosteoblasts – balanced activity – balanced activity
• In young adult – 1/5 of skeleton is In young adult – 1/5 of skeleton is demolished & rebuilt each yeardemolished & rebuilt each year
ExerciseExercise
• Electrical fieldsElectrical fields are generated by bone are generated by bone crystals when stressedcrystals when stressed
• Osteoblasts attracted to these areas Osteoblasts attracted to these areas • Osteoblasts induced to produce more Osteoblasts induced to produce more
bone matrixbone matrix• Effects:Effects:
stronger, thicker bonestronger, thicker bone larger tuberosities for larger muscleslarger tuberosities for larger muscles
Note effects of little exercise or paralysisNote effects of little exercise or paralysis
Nutrition & HormonesNutrition & Hormones
• Factors affecting bone growth, Factors affecting bone growth, developmentdevelopment, & , & maintenancemaintenance
1)1) dietary Cadietary Ca2+2+ & PO & PO443-3-; ; Fe, Fl, Mg, Fe, Fl, Mg,
Mn also required in small amountsMn also required in small amounts
2)2) calcitriolcalcitriol – – hormonehormone synthesized in synthesized in kidneys essential for absorption of Cakidneys essential for absorption of Ca2+2+ & & POPO44
3-3-; derived from vitamin D; derived from vitamin D33 (from skin (from skin adipose tissue)adipose tissue)
3)3) vitamin Cvitamin C – – required by enzymes making required by enzymes making collagencollagen
Nutrition & HormonesNutrition & Hormones
4)4) other vitaminsother vitamins vitamin Avitamin A – stimulates osteoblast – stimulates osteoblast
activityactivity vitamins K & Bvitamins K & B1212 – required by enzymes – required by enzymes
making bone proteinsmaking bone proteins
5)5) hormoneshormones growth hormonegrowth hormone – pituitary hormone; – pituitary hormone;
stimulates protein synthesis throughout stimulates protein synthesis throughout bodybody
thyroxinethyroxine – thyroid gland hormone; – thyroid gland hormone; stimulates metabolism to produce ATP stimulates metabolism to produce ATP energy for synthesisenergy for synthesis
Nutrition & HormonesNutrition & Hormones
6)6) sex hormonessex hormones androgensandrogens – – male sex hormonesmale sex hormones of the of the
testes; stimulate higher rate of testes; stimulate higher rate of osteoblast activityosteoblast activity
estrogensestrogens – – female sex hormonesfemale sex hormones of the of the ovaries; stimulate higher rate of ovaries; stimulate higher rate of osteoblast activityosteoblast activity
• Parathyroid hormoneParathyroid hormone & & calcitonincalcitonin – – maintain maintain homeostatic levelshomeostatic levels of Ca of Ca2+2+ & PO& PO44
3-3- in body fluids in body fluids
Calcium ReservesCalcium Reserves
Skeletal function – store CaSkeletal function – store Ca2+2+ & PO & PO443-3-
• parathyroid hormone parathyroid hormone ((PTHPTH)) produced by parathyroid glandsproduced by parathyroid glands activityactivity::
1)1) stimulate osteoclast activitystimulate osteoclast activity2)2) rate of absorption of Ca ions by intestinerate of absorption of Ca ions by intestine3)3) rate of Ca ion excretion from kidneyrate of Ca ion excretion from kidney
resultresult: : [Ca [Ca2+2+] in blood & other body ] in blood & other body fluidsfluids
Calcium ReservesCalcium Reserves
Skeletal function – store CaSkeletal function – store Ca2+2+ & PO & PO443-3-
• calcitonincalcitonin produced by thyroid glandproduced by thyroid gland activityactivity::
1)1) inhibit osteoclast activityinhibit osteoclast activity
2)2) rate of Ca ion excretion from kidney rate of Ca ion excretion from kidney
resultresult: : [Ca [Ca2+2+] in blood & other body ] in blood & other body fluidsfluids
Thyroid
Gland
BLOOD
Ca2+/PO43-
diet
fast
Parathyroid Glands
calcitonin
parathormone
MINERAL BONE
(HYDROXYAPATITE)
INHIBIT OSTEOCLAST
STIMULATE OSTEOCLAST
Control of Blood Calcium & Phosphate
OSTEOBLAST Activity
[Ca[Ca2+2+] Increase & ] Increase & Decrease in Body FluidsDecrease in Body Fluids
Fracture RepairFracture Repair
• Step 1:Step 1: fracture hematomafracture hematoma - extensive bleeding - extensive bleeding
followed by blood clotfollowed by blood clot
• Step 2:Step 2: internal callusinternal callus – network of spongy bone – network of spongy bone
forms to unite inner surfacesforms to unite inner surfaces external callusexternal callus – network of cartilage & bone – network of cartilage & bone
stabilizes outer edgesstabilizes outer edges
Fracture RepairFracture Repair
• Step 3:Step 3: spongy bone bracespongy bone brace – unites internal & – unites internal &
external bone surfaces as external callus external bone surfaces as external callus cartilage is replaced by bonecartilage is replaced by bone
remodelingremodeling - bone fragments & dead bone - bone fragments & dead bone replacedreplaced
• Step 4:Step 4: swellingswelling – at site of fracture – at site of fracture eventually replaced by remodelingeventually replaced by remodeling
Injury to Bone & MuscleInjury to Bone & Muscle
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 1-3/4 minASF Video plays about 1-3/4 min
Aging & The Skeletal Aging & The Skeletal SystemSystem
• OsteopeniaOsteopenia inadequate ossification during normal inadequate ossification during normal
remodelingremodeling begins age 30-40begins age 30-40 osteoblast activity declines whileosteoblast activity declines while
osteoclast activity remains normalosteoclast activity remains normal bone loss:bone loss:
men – 3% / yrmen – 3% / yrwomen – 8% / yrwomen – 8% / yr
Aging & The Skeletal Aging & The Skeletal SystemSystem
• OsteoporosisOsteoporosis caused by osteopeniacaused by osteopenia impairment of normal functionimpairment of normal function sex hormone influencesex hormone influence
menmen – produce – produce testosteronetestosterone until late in until late in life; osteoporosis not a problem until after life; osteoporosis not a problem until after 6060
womenwomen – cease – cease estrogenestrogen production in production in late 40s early 50slate 40s early 50s
Surface Features Surface Features Of BoneOf Bone
• Bone MarkingsBone Markings
• Skeletal TerminologySkeletal Terminology
Learning ObjectivesLearning Objectives
• ObjectiveObjective TermTerm:: Identify the major types of bone Identify the major types of bone
markings & explain their functional markings & explain their functional significancesignificance
Elevations & ProjectionsElevations & Projections
• General:General: processprocess – any projection or bump – any projection or bump ramusramus – extension of bone forming an angle – extension of bone forming an angle
• Tendon & ligament attachments:Tendon & ligament attachments: trochantertrochanter – large, rough projection (femur) – large, rough projection (femur) tuberositytuberosity – smaller, rough projection – smaller, rough projection tubercletubercle – small, rounded projection – small, rounded projection crestcrest – prominent ridge – prominent ridge lineline – low ridge – low ridge
Elevations & ProjectionsElevations & Projections
• Articular processes:Articular processes: headhead – expanded, articular end of an – expanded, articular end of an
epiphysis; separated from the shaft by a epiphysis; separated from the shaft by a “neck”“neck”
neckneck – narrow connection betw/ the – narrow connection betw/ the epiphysis & diaphysisepiphysis & diaphysis
condylecondyle – smooth, rounded articular surface – smooth, rounded articular surface
Trochanter; Head; Neck; Trochanter; Head; Neck; CondyleCondyle
TuberosityTuberosity
Crest; LineCrest; Line
Elevations & ProjectionsElevations & Projections
• Articular processes: (cont)Articular processes: (cont) trochleatrochlea – smooth, grooved articular – smooth, grooved articular
process; pulley-shapedprocess; pulley-shaped facetfacet – small, flattened articular surface – small, flattened articular surface spinespine – pointed process – pointed process
TrochleaTrochlea
Facet; SpineFacet; Spine
DepressionsDepressions
fossafossa – shallow depression – shallow depression sulcussulcus – narrow groove – narrow groove
Fossa; SulcusFossa; Sulcus
OpeningsOpenings
foramenforamen (pl. foramina) – shallow, rounded (pl. foramina) – shallow, rounded passageway for blood vessels &/or nervespassageway for blood vessels &/or nerves
meatusmeatus (or canal) – tube-like passageway for (or canal) – tube-like passageway for nerves or blood vesselsnerves or blood vessels
fissurefissure – elongate cleft – elongate cleft sinussinus (or antrum) – chamber w/in a bone; (or antrum) – chamber w/in a bone;
normally filled w/ air normally filled w/ air
Foramen; FossaForamen; Fossa
MeatusMeatus
MeatusMeatus
Sinus; FissureSinus; Fissure
Bone FeaturesBone Features
Bones & CartilageBones & Cartilage
• To View Video:To View Video:– Move mouse cursor over slide title-linkMove mouse cursor over slide title-link– When hand appears, click onceWhen hand appears, click once
• ASF Video plays about 1-3/4 minASF Video plays about 1-3/4 min