Section 1 Bones and Joints

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Transcript of Section 1 Bones and Joints

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Bone Tissue DevelopmentBone Tissue DevelopmentThereThere areare threethree mainmain typestypes ofof cellscells involvedinvolvedinin bonebone development,development, growthgrowth andand remodellingremodelling..

OsteoblastsOsteoblastsOsteocytesOsteocytes

OsteoclastsOsteoclasts

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Bone Tissue DevelopmentBone Tissue Development

BoneBone forming cellsforming cellsFound in -

Deeper layers of the periosteumCentre of ossification

At the ends of the diaphysis to the epiphyseal

cartilages of long bones

Fracture sites

OsteoblastsOsteoblasts

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Bone Tissue DevelopmentBone Tissue Development

MatureMature osteoblastsosteoblastsWhen bone develops osteoblastsbecome trapped and remainisolated.

They stop forming new bone andbecome inactive- at this point theyhave become osteocytes.

OsteocytesOsteocytes

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Bone Tissue DevelopmentBone Tissue Development

Bone reabsorption and remodellingThese cells reabsorb bone by breaking down osteocyteshelping to maintain the optimum shape of the bone.

Osteoclasts release enzymes which breakdown the proteincomponents of the matrix and pump hydrogen ions whichreduces the pH which aids decalcification

DecalcificationWhen bone cells (Osteocytes) are broken down byOsteoclasts to allow new cells to take their place andcalcium is lost from the bone

OsteoclastsOsteoclasts

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Bone growthBone growthBlood vesselsBlood vessels

PeriosteumPeriosteum

Bone collarBone collar

HyalineHyaline

cartilagecartilagemodelmodel

MedullaryMedullary cavitycavity

ArticularArticular cartilagecartilageSpongy boneSpongy bone

EpiphysealEpiphyseal plateplate

PeriosteumPeriosteumCompact boneCompact bone

PrimaryPrimaryossificationossification

centrecentre

SecondarySecondary

ossificationossificationcentrecentre

The hyalinecartila e model has

the approximateshape of the boneto be developed.

Osteoblasts producecancellous bone onthe surface of the

cartila e model whichforms the bone collar

A primary ossificationcentre forms as blood

vessels and osteoblasts

invade the calcifiedcartila e.The osteoblasts lay down

bone matrix formincancellous bone.

Calcified cartila estarts to form in the

epiphyses which leadsto the formation of

secondaryossification sites.

The medullary cavitybe ins to form in the

centre of thediaphysis.

The ori inalcartila e model isalmost completely

ossified. Unossifiedcartila e becomes

the epiphyseal plateand the articular

cartila e .

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Bone growthBone growth ² ² hormonal influenceshormonal influencesHormone Source FunctionGrowthhormone

Anteriorpituitary

land

Stimulates the liver andother tissues to secrete

Insulin-li e rowthfactor-1 (IGF-1)

IGF-1 stimulates rowthof chondrocytes(cartila e tissue)

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Bone growthBone growth ² ² hormonal influenceshormonal influencesHormone Source FunctionThyroidhormone

(T 3)

Thyroidland

W or s in syner y withGrowth hormone

Is required for bonerowth durin childhood.

Re ulates bone turnoverand mineralisationthrou hout adulthood

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Bone growthBone growth ² ² hormonal influenceshormonal influencesHormone Source FunctionOestro en

Tetosterone

Formative tas 1.1

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OsteoporosisOsteoporosis

It is believed that the condition ofosteoporosis occurs when osteoclastactivity (over a number of years) has

resulted in the brea down of more bonetissue than has been replaced which has

led to wea er bones.

Osteoporosis literallymeans ´porousµ bones and

is often referred to as

´fra ile boneµ disease. 1 in 3 women and 1 in 12

men over the a e of 50 will sustain a spine, hipor wrist fracture due

to osteoporosis

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OsteoporosisOsteoporosis

tors i i re ses s epti ilit to evelopi gosteoporosis i l e -

Ge esAgeGe erR e

o o eig tPrevio s fr t resSo e e i l o itio s

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´It·s not all´It·s not allaboutabout

calcium andcalcium andvitamin Dµvitamin Dµ

Bone healthBone health

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Identification of major bones

Identification of major bones

Revision activity 1.Revision activity 1.

Bone typesBone typesFormative task 1.2Formative task 1.2

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JointsJointsMuscles pull on bones to make them move butMuscles pull on bones to make them move butmovement would not be possible without jointsmovement would not be possible without joints

between bones.between bones.

A joint or articulation is a place where two bonesA joint or articulation is a place where two bones

come togethercome togetherThree classificationsThree classifications ² ²

Fibrous or fixed jointFibrous or fixed joint

Slightly moveable /Slightly moveable / CartiliginousCartiliginous joint jointFreely moveable / synovial jointFreely moveable / synovial joint

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JointsJointsJointC lassification

Functional significance Examples

Fibrous

Cartili inousConnected entirely bycartila e. Allows for onlya small amount ofmovement

Manubriosternal jointInvertebral discsPubic symphysis

Synovial

Formative tas 1.3

Examples of synovial joints ²refer to the handout

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The Shoulder girdle ² a closer look

There are three main joints that ma e upthe shoulder irdle,

these are -Glenohumeral joint

Sternoclavicular joint

cromioclavicular joint

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The Glenohumeral joint ² a closer look

Bones that ma e up the jointhumeruslenoid cavity of scapula

Ball and Soc et joint

Ran es of movementadduction / abductionflexion / extensionmedial / lateral rotation

circumduction

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The Sternoclavicular joint ² a closer look

Bones that ma e up the jointclaviclesternum (manubrium)1st costal cartila e

Strictly a saddle jointRan es of movement(ball and soc et li e movements)

Abduction / adductionFlexion / extensionCircumduction

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The Knee ² a closer look

The nee is the lar est synovial joint of the human body.

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The Knee ² a closer look

There are two main joints thatma e up the nee, these are -

The shoulder girdle consists of the following articulations ±

Tibio-femoral jointPatellofemoral joint

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The Tibio-femoral joint ² a closer look

Bones that ma e up the jointfemurtibia

in e jointRan es of movement(180º ran e)

Flexion / extension

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The Patella-femoral joint ² a closer look

Bones that ma e up the jointfemur (trochlear roove)patella

Glidin jointRan es of movement

Slidin / lidinmovement in and aroundthe trochlear roove.

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Formative task 1.4

Articulations ofthe Elbow joint

Articulations ofthe Ankle joint

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T heT he s y no v ia l j oints y no v ia l j oint ±± aa c los e r lookc los e r look

FemurFemur

FibulaFibulaTibiaTibia

PatellaPatella

BursaBursa

BursaBursa

ArticularArticular cartila ecartila e

ArticularArticular cartila ecartila e

Patella tendonPatella tendon

Synovial fluidSynovial fluid

Synovial membraneSynovial membrane

FatFatMeniscusMeniscus

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T heT he s y no v ia l j oints y no v ia l j oint ±± anan ex amp leex amp le

FemurFemur

FibulaFibulaTibiaTibia

PatellaPatellaSynovial membraneSynovial membrane

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T heT he s y no v ia l j oints y no v ia l j oint ±± anan ex amp leex amp le

FemurFemur

FibulaFibulaTibiaTibia

PatellaPatella

Synovial fluidSynovial fluid

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T heT he s y no v ia l j oints y no v ia l j oint ±± anan ex amp leex amp le

FemurFemur

FibulaFibulaTibiaTibia

PatellaPatella

MeniscusMeniscus

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T heT he s y no v ia l j oints y no v ia l j oint ±± anan ex amp leex amp le

FemurFemur

FibulaFibulaTibiaTibia

PatellaPatellaBursaBursa

BursaBursa

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T heT he s y no v ia l j oints y no v ia l j oint ±± anan ex amp leex amp le

FemurFemur

FibulaFibulaTibiaTibia

PatellaPatella

FatFat

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T he ve rt eb ra l co lumn T he ve rt eb ra l co lumn ±± a c los e r looka c los e r look

Cervical

Thoracic

umbar

SacralCoccyx

C 1-7

T 1-12

1-5

S 1-5 4

The spine's naturalcurves position the

head over the pelvisand wor as shocabsorbers to

distribute mechanicalstress durin

movement.

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T he ve rt eb ra l co lumn T he ve rt eb ra l co lumn ±± a c los e r looka c los e r look

In between the vertebraare discs which are

composed of cartila e andact as shoc absorbers.

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The spine needs a natural curve tofunction correctly. This is due to theshape of the individual vertebrae.

If the curve becomes too reat thenstress is placed on other parts of thespine causin pain.

Scoliosisordosis

Kyphosis

Ab norma l cur v atur e s of t he spin eAb norma l cur v atur e s of t he spin e

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Kyphosis

The term ´Kyphosisµ refers toexcessive curvature of theupper spine. The bactherefore appears hunchedand more rounded than normal.

Ti htenin of the pectoralmuscles is common in thiscondition.

Ab norma l cur v atur e s of t he spin eAb norma l cur v atur e s of t he spin e

Kyphosis

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KyphosisW hat causes yphosis?

Ab norma l cur v atur e s of t he spin eAb norma l cur v atur e s of t he spin e

Poor posture over a number of yearsDiseases such as osteoarthiritis and osteoporosiswhich affect the spine

Children may have yphosis but the causes areun nown

Kyphosis

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LordosisW hat causes Lordosis?

Ab norma l cur v atur e s of t he spin eAb norma l cur v atur e s of t he spin e

Bein overwei ht

W ea abdominal muscles or poor posture

Havin phosis ma even lead to Lordosis

Lordosis

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Ab norma l cur v atur e s of t he spin eAb norma l cur v atur e s of t he spin e

ScoliosisThe term ´Scoliosisµ comes fromthe Gree word ́ curvatureµ andsimply indicates an abnormallateral curvature of the spine.This occurs most often in theupper chest area or lower bac .

It is believed thatapproximately 2% of thepopulation have Scolosis

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ScoliosisW hat causes Scoliosis?

Ab norma l cur v atur e s of t he spin eAb norma l cur v atur e s of t he spin e

Con enital ² born with the condition

Diseases such as muscular dystrophy which causewea ness around the spine.

If the lower limbs are not the same len th

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FlexionFlexionBendinBendin

movementmovement

DecreasinDecreasinthethe an le atan le at

aa joint joint

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ExtensionExtension

Strai hteninStrai hteninmovementmovement

Increasin theIncreasin thean lean le at theat the

joint joint

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AbductionAbduction

Movement ofMovement of

a body parta body partaway fromaway fromthe midline ofthe midline ofthethe bodybody

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RotationRotationRotationRotation -- Turnin of a structure around aTurnin of a structure around acentral axis and cancentral axis and can bebe

Medial or LateralMedial or Lateral

Occurs in theOccurs in the tranversetranverse plane of motionplane of motion

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Medial Rotation

Medial RotationTurninTurnin ofof

a structurea structurearound aaround acentralcentralaxisaxis inin

towardstowardsthe midlinethe midline

of theof thebody.body.

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Lateral Rotation

Lateral RotationTurninTurnin ofof

a structurea structurearound aaround acentralcentral

axisaxisoutwardsoutwardsfrom thefrom themidline ofmidline ofthe body.the body.

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Inversion andInversion and EversionEversionSpecialised movement of the an le.Specialised movement of the an le.

InversionInversion

TiltinTiltinof soleof soleinwardsinwards

EversionEversion

Tiltin ofTiltin of

solesoleoutwardsoutwards

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DorsiflexionDorsiflexionM ovementM ovement

term forterm forflexion offlexion ofthe an lethe an le

joint. joint.

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Circumduction

CircumductionSpeciallisedSpeciallised

movementmovementwhich involveswhich involves

flexion,flexion,extension,extension,abduction,abduction,

adduction andadduction androtation.rotation.

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DepressionDepressionM ovementM ovement

in anin aninferiorinferiordirection.direction.

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ElevationElevationM ovementM ovementin a superiorin a superior

direction.direction.

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AnatomicalAnatomical planes of the bodyplanes of the body

In order to performanalysis of human

movement you must befamiliar with the

terminolo y that preciselyidentifies body position

The human body is dividedinto three anatomical

planesThese planes are

ima inary lines which aredrawn vertically orhorizontally throu h an

upri ht body.

Frontal

Sagittal

Horizontal

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The Frontal PlaneThe Frontal Plane

The frontal plane divides theThe frontal plane divides thebody from front to bac .body from front to bac .

Abduction and adductionAbduction and adductionmovements such as jumpinmovements such as jumpin

jac s or side bends occur in jac s or side bends occur inthis plane.this plane.

Performin aPerformin acartwheel is a primecartwheel is a prime

example of aexample of amovement within themovement within the

frontal plane.frontal plane.

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TheThe SagittalSagittal PlanePlane

TheThe sa ittalsa ittal plane cuts throu hplane cuts throu hthethe bodybody dividin it into twodividin it into twohalves, left and ri ht.halves, left and ri ht.

Flexion and extension movementsFlexion and extension movementsoccur in this plane i.e. bicep curlsoccur in this plane i.e. bicep curls

All movement involvin forwardAll movement involvin forwardand bac ward motion areand bac ward motion are

referred to asreferred to as sa ittalsa ittal planeplanemovements i.e. wal in , forwardmovements i.e. wal in , forwardroll etc.roll etc.

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The Horizontal PlaneThe Horizontal PlaneThe horizontal plane cutsThe horizontal plane cutsthrou h the body dividinthrou h the body dividin

it into two halves, theit into two halves, theupper and lower half.upper and lower half.

RotationalRotationalmovements such asmovements such as

pronation,pronation,supination andsupination and

rotation occurs inrotation occurs in

this plane.this plane.A twist performed by a diver or trampolinistA twist performed by a diver or trampolinistare examples of horizontal plane movement.are examples of horizontal plane movement.

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Axis of RotationAxis of RotationAn axis is a strai ht line throu h which somethin rotates.An axis is a strai ht line throu h which somethin rotates.

M ovement around joints ta es place in a plane around anM ovement around joints ta es place in a plane around anaxis and there are three axis of rotation.axis and there are three axis of rotation.

There are three reference axes for describin humanThere are three reference axes for describin humanmotionmotion

TheThe FrontalFrontal axisaxis

TheThe SSa ittala ittal axisaxisTheThe VerticalVertical axisaxis

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Axis of RotationAxis of RotationTheThe FrontalFrontal axisaxis

The frontal axis lies at a ri ht an le to theThe frontal axis lies at a ri ht an le to the sa ittalsa ittal planeplane

TheThe SSa ittala ittal axisaxisTheThe sa ittalsa ittal axis has the same direction as theaxis has the same direction as the sa ittalsa ittal

plane and lies at a ri ht an le to the frontal planeplane and lies at a ri ht an le to the frontal plane

The Vertical axisThe Vertical axis

The vertical axis runs strai ht down throu h the top ofThe vertical axis runs strai ht down throu h the top ofthe head and is at a ri ht an le to the horizontal plane ofthe head and is at a ri ht an le to the horizontal plane ofmovementmovement