Download - Anatomy of Skeletal System. SKELETAL SYSTEM COMPOSED OF: COMPOSED OF: -Bones -Bones -Cartilage -Cartilage -Joints -Joints -Ligaments -Ligaments

Anatomy of Skeletal SystemAnatomy of Skeletal System

SKELETAL SYSTEMSKELETAL SYSTEM

COMPOSED OF:COMPOSED OF:

-Bones-Bones

-Cartilage-Cartilage

-Joints-Joints

-Ligaments-Ligaments

Functions of Skeletal Functions of Skeletal SystemSystem SUPPORTSUPPORT: : Hard framework that supports and Hard framework that supports and

anchors the soft organs of the body.anchors the soft organs of the body.

PROTECTIONPROTECTION: : Surrounds organs such as the Surrounds organs such as the brain and spinal cord.brain and spinal cord.

MOVEMENT:MOVEMENT: Allows for muscle attachment Allows for muscle attachment therefore the bones are used as levers.therefore the bones are used as levers.

STORAGE:STORAGE: Minerals and lipids are stored within Minerals and lipids are stored within bone material.bone material.

BLOOD CELL FORMATIONBLOOD CELL FORMATION: : The bone marrow is The bone marrow is responsible for blood cell production.responsible for blood cell production.

Bone MarkingsBone Markings

Slide 5.9Slide 5.9Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Bone Surface is not smooth, but shows:

Bone markings which reveal where:

-muscles, tendons, and ligaments attatched

-nerves and blood vessels pass

*bone marking may be:

1-projections or processes or

2-depressions or cavities

StructureStructure Compact boneCompact bone

Outer layer of bone, very hard and dense.Outer layer of bone, very hard and dense. Organized in structural units called Organized in structural units called Haversian Haversian

systemssystems.. Matrix is composed of Ca salts (Ca carbonate Matrix is composed of Ca salts (Ca carbonate

and Ca phosphate)and Ca phosphate) OsteocytesOsteocytes – living bone cells that live in matrix. – living bone cells that live in matrix.

Porous (Spongy) bonePorous (Spongy) bone Located in the ends of long bones.Located in the ends of long bones. Many spaces that are filled with red bone Many spaces that are filled with red bone

marrow which produces bone cells.marrow which produces bone cells.

StructureStructure

Spongy boneSpongy bone (cont’d) (cont’d) Trabeculae – needle-like threads of Trabeculae – needle-like threads of

spongy bone that surround the spaces. spongy bone that surround the spaces. Add strength to this portion of the bone.Add strength to this portion of the bone.

CartilageCartilage Matrix is a firm gel with chondrocytes Matrix is a firm gel with chondrocytes

suspended in the matrix.suspended in the matrix.

Classification of BonesClassification of Bones

Slide 5.4aSlide 5.4aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Long bones

Typically longer than wide

Have a shaft with heads at both ends

Contain mostly compact bone

• Examples: Femur, humerus


Slide 5.4bSlide 5.4bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Short bones

Generally cube-shape

Contain mostly spongy bone

Examples: Carpals, tarsals

Classification of Bones on the Classification of Bones on the Basis of ShapeBasis of Shape

Slide 5.4cSlide 5.4c

Figure 5.1



Flat bones

Thin and flattened

Usually curved

Thin layers of compact bone around a layer of spongy bone

Examples: Skull, ribs, sternum



Irregular bones

Irregular shape

Do not fit into other bone classification categories

Example: Vertebrae and hip

Gross Anatomy of a Long BoneGross Anatomy of a Long Bone


Diaphysis

Shaft

Composed of compact bone

Epiphysis

Ends of the bone

Composed mostly of spongy bone

Figure 5.2a

Structures of a Long BoneStructures of a Long Bone


Periosteum Outside covering of

the diaphysis

Fibrous connective tissue membrane

Sharpey’s fibers Secure periosteum to

underlying bone

Arteries Supply bone cells

with nutrientsFigure 5.2c



Articular cartilage

Covers the external surface of the epiphyses

Made of hyaline cartilage

Decreases friction at joint surfaces Figure 5.2a



Medullary cavity

Cavity of the shaft

Contains yellow marrow (mostly fat) in adults

Contains red marrow (for blood cell formation) in infants Figure 5.2a

Microscopic Anatomy of BoneMicroscopic Anatomy of Bone

Slide Slide 5.10a5.10a

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Osteon (Haversian System)

A unit of bone

Central (Haversian) canal

Opening in the center of an osteon

Carries blood vessels and nerves

Perforating (Volkman’s) canal

Canal perpendicular to the central canal

Carries blood vessels and nerves


Slide Slide 5.10b5.10b


Figure 5.3




Lacunae Cavities containing

bone cells (osteocytes)

Arranged in concentric rings

Lamellae Rings around the

central canal

Sites of lacunae Figure 5.3




Canaliculi

Tiny canals

Radiate from the central canal to lacunae

Form a transport system

Figure 5.3

Changes in the Human SkeletonChanges in the Human Skeleton


In embryos, the skeleton is primarily hyaline cartilage

During development, much of this cartilage is replaced by bone

Cartilage remains in isolated areas

Bridge of the nose

Parts of ribs

Joints

Bone GrowthBone Growth



Epiphyseal plates allow for growth of long bone during childhood

New cartilage is continuously formed

Older cartilage becomes ossified

Cartilage is broken down

Bone replaces cartilage

Bone GrowthBone Growth



Bones are remodeled and lengthened until growth stops

Bones change shape by gravity &muscle pull

Bones grow in width through periostium

Long Bone Formation and GrowthLong Bone Formation and Growth



Figure 5.4a

Long Bone Formation and GrowthLong Bone Formation and Growth



Figure 5.4b

Types of Bone CellsTypes of Bone Cells


Osteocytes Mature bone cells

Osteoblasts Bone-forming cells

Osteoclasts Bone-destroying cells

Break down bone matrix for remodeling and release of calcium

Bone remodeling is a process by both osteoblasts and osteoclasts

FracturesFractures

Closed fracture (simple): skin is intactClosed fracture (simple): skin is intact Open fracture (compound): skin is Open fracture (compound): skin is

openopen Fracture reduction :Fracture reduction :

1-closed reduction ,no surgery is 1-closed reduction ,no surgery is neededneeded

2-open reduction ,surgery is needed2-open reduction ,surgery is needed

Repair of fractureRepair of fracture

Healing timeHealing time for simple fracture is 6- for simple fracture is 6-8 weeks (longer in elderly people)8 weeks (longer in elderly people)

It occurs in FOURIt occurs in FOUR major events major events 1-hematoma formation1-hematoma formation 2-fibrocartilage callus formation2-fibrocartilage callus formation 3-bony callus formation3-bony callus formation 4-bone remodelling4-bone remodelling

Skeletal system includesSkeletal system includes Axial divisionAxial division

Skull and associated bonesSkull and associated bones Auditory ossiclesAuditory ossicles Hyoid bonesHyoid bones

Vertebral columnVertebral column Thoracic cage(Ribs+ sternum)Thoracic cage(Ribs+ sternum)

• Appendicular division

-Pectoral girdle-Pelvic girdle

The Axial SkeletonThe Axial Skeleton Axial divisionAxial division

Skull and associated Skull and associated

bones:bones: Auditory ossiclesAuditory ossicles Hyoid bonesHyoid bones

Vertebral columnVertebral column Thoracic cageThoracic cage

Ribs + sternumRibs + sternum

The Skull and Associated The Skull and Associated BonesBones

SuturesSutures Sutures – Immovable joints that join skull Sutures – Immovable joints that join skull

bones togetherbones together Form boundaries between skull bonesForm boundaries between skull bones Four sutures:Four sutures:

Coronal – between parietal and frontalCoronal – between parietal and frontal Sagittal– between parietal bonesSagittal– between parietal bones Lambdoid – between the parietal and Lambdoid – between the parietal and

occipitaloccipital Squamous – between the parietal and Squamous – between the parietal and

temporaltemporal Fontanels Fontanels – usually ossify by 2 years of age– usually ossify by 2 years of age

Frontal(Coronal)

Sagittal

Squamous

Lambdoid

Sutures

•skull = 22 bones•cranium = 8 bones: frontal, occipital, 2 temporals, 2 parietals, sphenoid and

ethmoid•facial bones = 14 bones: nasals, maxillae, zygomatics, mandible, lacrimals,

palatines, inferior nasal conchae, vomer.

•skull forms a larger cranial cavity-also forms the nasal cavity, the orbits, paranasal sinusesmandible and auditory ossicles are the only movable skull bones

•cranial bones also: attach to membranes called meninges-stabilize positions of the brain, blood vessels-outer surface provides large areas for muscle attachment that move the head or provide facial expressions

The Adult SkullThe Adult Skull

Bones of the Cranium

Frontal View

Frontal

Frontal View

Parietal

Frontal View

Temporal

Frontal View

Nasal

Frontal View

Vomer

Frontal View

Zygoma

Frontal View

Maxilla

Frontal View

Mandible

Frontal View

FrontalParietal

Temporal

Zygoma

Nasal

Vomer

Maxilla

Mandible

Frontal View

Lateral View

Frontal

Lateral View

Parietal

Lateral View

Temporal

Lateral View

Nasal

Lateral View

Zygoma

Lateral View

Maxilla

Lateral View

Mandible

Lateral View

Occipital

Lateral View

Mastoid Process

Lateral View

External Auditory Meatus

Lateral View

Frontal

Nasal

ZygomaMaxilla

Mandible

Parietal

Sphenoid

Temporal

Occipital

External Auditory Meatus

Mastoid Process

Lateral View

Figure 6.4 Sectional Figure 6.4 Sectional Anatomy of the Skull, Part IAnatomy of the Skull, Part I

Frontal boneFrontal bone Forms the foreheadForms the forehead Roof of the orbitRoof of the orbit articulates with articulates with

parietal, sphenoid, parietal, sphenoid, lacrimal, nasal, lacrimal, nasal, ethmoid, zygomatic ethmoid, zygomatic and maxillaand maxilla

superior and lateral superior and lateral to glabellar region – to glabellar region – frontal sinusesfrontal sinuses

inferior portion – inferior portion – supraorbital supraorbital ridgesridges with with supraorbital supraorbital notchnotch (supraorbital (supraorbital nerve and artery)nerve and artery)

•Parietal bones-Part of the superior and lateral surfaces of the cranium-articulate with each other – sagittal suture-articulate with occipital, frontal,temporal and sphenoid bones

•Temporal bone-Forms wall of jugular foramen-Petrous part: posterior portion-Tympanic part: associated with ear canal-Squamous part: anterior portion, fan-shaped

-zygomatic process-forms cranial portion of the TMJ joint-inferior to zygo. process – mandibular fossa (mandibular condyle)

•Temporal bone – petrous portion•houses the inner ear-inferior aspect – mastoid process (air spaces that communicate with the middleear)

-also for attachment of sternocleidomastoid muscle-inferior to mastoid process – mastoid foramen-anterior to mastoid process – external acoustic meatus-inferior and medial to the MP – styloid process (muscle attachment)

-stylomastoid foramen (7th cranial)

Occipital boneOccipital bone Part of the base of the skullPart of the base of the skull articulates with parietal, articulates with parietal,

temporal and sphenoidtemporal and sphenoid Surrounds the foramen magnumSurrounds the foramen magnum lateral to the FM – lateral to the FM – hypoglossal hypoglossal

canalcanal (12 (12thth cranial) cranial) projections = projections = occipital occipital

condylescondyles Forms part of the jugular Forms part of the jugular

foramenforamen

Sphenoid boneSphenoid bone Contributes to floor of Contributes to floor of

craniumcranium articulates with the articulates with the

frontal, ethmoid, frontal, ethmoid, temporaltemporal

zygomatic, parietal zygomatic, parietal maxillary, palatine, maxillary, palatine, vomer & occipital vomer & occipital bonesbones

Bridges cranial and Bridges cranial and facial bonesfacial bones

Optic canal allows Optic canal allows passage of optic nervepassage of optic nerve

Ethmoid boneEthmoid bone Irregularly shaped boneIrregularly shaped bone Forms part of orbital wallForms part of orbital wall Forms roof of nasal cavityForms roof of nasal cavity articulates with: frontal, articulates with: frontal,

sphenoid, lacrimal and maxillary sphenoid, lacrimal and maxillary bonesbones

connects with the vomerconnects with the vomer two lateral masses – contain the two lateral masses – contain the

ethmoid sinusesethmoid sinuses projections called the superior projections called the superior

and middle nasal conchaeand middle nasal conchae two plates: two plates: perpendicular perpendicular

plateplate

& the cribiform plate& the cribiform plate Cribiform plate:Cribiform plate: perforations perforations

for olfactory nerve, midline is for olfactory nerve, midline is the crista gallithe crista galli

Perpendicular platePerpendicular plate = upper = upper part of nasal septumpart of nasal septum

14 Facial Bones14 Facial Bones

Nasal (2) Maxillae (2) Zygomatic (2)Nasal (2) Maxillae (2) Zygomatic (2)Mandible (1) Lacrimal (2) Palatine (2)Mandible (1) Lacrimal (2) Palatine (2)

Inferior nasal conchae (2) Vomer (1)Inferior nasal conchae (2) Vomer (1)

Bones of the FaceBones of the Face MaxillaeMaxillae

Paired bonePaired bone Largest of facial Largest of facial

bonesbones Form upper jawForm upper jaw body = orbital, body = orbital,

nasal, nasal, infratemporal infratemporal and facial and facial surfacessurfaces

body contains body contains the maxillary the maxillary sinusessinuses

Maxillary bones: Anterior Maxillary bones: Anterior ViewView

frontal process – articulates with frontal bone and nasal bones & frontal process – articulates with frontal bone and nasal bones & forms medial orbital rimforms medial orbital rim

facial surface – body of maxillafacial surface – body of maxilla infraorbital forameninfraorbital foramen – landmark for local – landmark for local inferior to this IF – inferior to this IF – canine fossacanine fossa inferior portion of the maxilla – inferior portion of the maxilla – alveolar processesalveolar processes of the teeth of the teeth

(contains the roots of the maxillary teeth(contains the roots of the maxillary teeth

Zygomatic BonesZygomatic Bones

CheekbonesCheekbones Lateral wall of orbit along with sphenoidLateral wall of orbit along with sphenoid Part of zygomatic arch along with part of Part of zygomatic arch along with part of

temporaltemporal

Palatine bonesPalatine bones Small, L-shapedSmall, L-shaped link between maxilla and sphenoidlink between maxilla and sphenoid Form posterior portion of hard palateForm posterior portion of hard palate Contribute to floor of orbitContribute to floor of orbit made up of horizontal made up of horizontal

plate and a vertical plate plate and a vertical plate

+ orbital process+ orbital process

Inferior nasal conchaInferior nasal concha Located on each side of nasal septumLocated on each side of nasal septum Increase epithelial surface Increase epithelial surface Create turbulence in inspired airCreate turbulence in inspired air

Lacrimal bonesLacrimal bones Smallest bones in skullSmallest bones in skull Forms nasolacrimal groove leading to nasolacrimal canalForms nasolacrimal groove leading to nasolacrimal canal Delivers tears to nasal cavityDelivers tears to nasal cavity

Palatine & VomerPalatine & Vomer

VomerVomer posterior part of nasal septumposterior part of nasal septum Forms inferior portion of nasal septumForms inferior portion of nasal septum Articulates with maxillae and palatinesArticulates with maxillae and palatines

MandibleMandible lower jawlower jaw only freely movable bone of the only freely movable bone of the

skullskull moving articulations with moving articulations with

temporal bonetemporal bone

-visible are the genial tubercles – or mental spines-muscle attachment area

-two fossas: 1) sublingual (sublingual salivary gl.)2) submandibular (submandibular gl.)

-divided by the mylohyoid line (mylohyoid m.)-mandibular foramen – opening of the mandibular canal

-for the exit of the alveolar nerve and vessels-can be lost with alveolar process reabsorption-overhanging the foramen – lingula (attachment of sphenomandibular ligament – TMJ)

Mandible: InferiorMandible: Inferior surface surface

The Hyoid BoneThe Hyoid Bone

Suspended by stylohyoid ligamentsSuspended by stylohyoid ligaments Consists of a body, greater horns and Consists of a body, greater horns and

lesser hornslesser horns Base for muscles of the tongue and Base for muscles of the tongue and

larynxlarynx

Paranasal SinusesParanasal Sinuses part of the nasal complexpart of the nasal complex Paired cavities in Paired cavities in

ethmoid, sphenoid, ethmoid, sphenoid, frontal and maxillaryfrontal and maxillary

Lined with mucous Lined with mucous membranes and open membranes and open into nasal cavity though into nasal cavity though openings called ostiaopenings called ostia

Resonating chambers for Resonating chambers for voice, lighten the skullvoice, lighten the skull

Sinusitis is inflammation Sinusitis is inflammation of the membrane of the membrane (allergy)(allergy)

infection can easily infection can easily spread from one sinus to spread from one sinus to the other through the the other through the nasal cavitynasal cavity

can also spread to other can also spread to other tissuestissues secondary sinusitissecondary sinusitis

frontal sinuses: frontal bone, separated by frontal sinuses: frontal bone, separated by a septuma septum

connects with nasal cavity – frontonasal connects with nasal cavity – frontonasal ductduct

sphenoid sinuses: body of the sphenoid sphenoid sinuses: body of the sphenoid bonebone

also drain into nasal cavityalso drain into nasal cavity ethmoid sinuses: or ethmoid air cells, ethmoid sinuses: or ethmoid air cells,

located in the lateral masseslocated in the lateral masses anterior, middle and posterior sinusesanterior, middle and posterior sinuses

maxillary: body of the maxillamaxillary: body of the maxilla size varies with individual and agesize varies with individual and age largest of the sinuseslargest of the sinuses close proximity to alveolar processes – close proximity to alveolar processes –

periodontal tissues may be in direct contact periodontal tissues may be in direct contact with sinus’ mucus membraneswith sinus’ mucus membranes

The Vertebral ColumnThe Vertebral Column

http://www.wisc-online.com/objects/index.asp?objID=AP12104

Adult Vertebral ColumnAdult Vertebral Column

26 vertebrae26 vertebrae 24 individual vertebrae24 individual vertebrae SacrumSacrum CoccyxCoccyx

Seven cervical vertebraeSeven cervical vertebrae Twelve thoracic vertebraeTwelve thoracic vertebrae Five lumbar vertebraeFive lumbar vertebrae Sacrum and coccyx areSacrum and coccyx are Fused together.Fused together.

Typical VertebraeTypical Vertebrae BodyBody weight bearingweight bearing

Vertebral archVertebral arch pediclespedicles laminaelaminae

Vertebral Vertebral foramenforamen

Seven Seven processesprocesses 2 transverse2 transverse 1 spinous 1 spinous 4 articular4 articular

Typical Cervical Vert. (C3-C7)Typical Cervical Vert. (C3-C7)

Smaller bodiesSmaller bodies Larger spinal canalLarger spinal canal Transverse Transverse

processesprocesses shortershorter transverse foramen transverse foramen

for vertebral arteryfor vertebral artery Spinous processes of Spinous processes of

C2 to C6 often bifidC2 to C6 often bifid 1st and 2nd cervical 1st and 2nd cervical

vertebrae are uniquevertebrae are unique atlas & axisatlas & axis

Atlas & Axis (C1-C2)Atlas & Axis (C1-C2)

The Atlas The Atlas

C1 is termed the C1 is termed the atlasatlas Lacks a body and spinous processLacks a body and spinous process Supports the skull Supports the skull

Superior articular facets receive the Superior articular facets receive the occipital condylesoccipital condyles

Allows flexion and extension of Allows flexion and extension of neck neck Nodding the head “yes”Nodding the head “yes”

Figure 7.16a

The Atlas The Atlas

The Axis The Axis

Has a body and spinous processHas a body and spinous process DensDens (odontoid process) projects (odontoid process) projects

superiorlysuperiorly Acts as a pivot for rotation of the Acts as a pivot for rotation of the

atlas and skullatlas and skull Participates in rotating the head from Participates in rotating the head from

side to sideside to side

The Axis The Axis

Thoracic Thoracic VertebraeVertebrae(T1-T12)(T1-T12)

All articulate with All articulate with ribsribs

Have heart-Have heart-shaped bodies shaped bodies from the superior from the superior viewview

Each side of the Each side of the body bears body bears demifacts for demifacts for articulation with articulation with ribsribs

Thoracic VertebraeThoracic Vertebrae

Spinous processes are long and Spinous processes are long and point inferiorlypoint inferiorly

Vertebral foramen are circularVertebral foramen are circular Transverse processes articulate Transverse processes articulate

with tubercles of ribswith tubercles of ribs Allows rotation and prevents Allows rotation and prevents

flexion and extensionflexion and extension

Lumbar VertebraeLumbar Vertebrae Bodies are thick Bodies are thick

and strong and strong Transverse Transverse

processes are processes are thin and taperedthin and tapered

Spinous rocesses Spinous rocesses are thick, blunt, are thick, blunt, and point and point

Vertebral Vertebral foramina are foramina are triangulartriangular

Allows flexion Allows flexion and extension – and extension – rotation rotation preventedprevented

Sacrum (SSacrum (S11 – S – S55))

Forms the posterior wall of pelvisForms the posterior wall of pelvis Formed from 5 fused vertebraeFormed from 5 fused vertebrae Superior surface articulates with LSuperior surface articulates with L55

Inferiorly articulates with coccyxInferiorly articulates with coccyx Sacral promontorySacral promontory

Where the first sacral vertebrae bulges into Where the first sacral vertebrae bulges into pelvic cavitypelvic cavity

Center of gravity is 1 cm posterior to Center of gravity is 1 cm posterior to sacral promontorysacral promontory

SacrumSacrum

Sacral foraminaSacral foramina Ventral foraminaVentral foramina

Passage for ventral rami of sacral spinal Passage for ventral rami of sacral spinal nervesnerves

Dorsal foraminaDorsal foramina Passage for dorsal rami of sacral spinal Passage for dorsal rami of sacral spinal

nervesnerves

SacrumSacrum

Figure 7.18a, b

CoccyxCoccyx

Is the “tailbone” Is the “tailbone” Formed from 3 – 5 fused vertebraeFormed from 3 – 5 fused vertebrae Offers only slight support to pelvic Offers only slight support to pelvic

organsorgans

Bony ThoraxBony Thorax Forms the framework of the chestForms the framework of the chest Components of the bony thoraxComponents of the bony thorax

Thoracic vertebrae – posteriorlyThoracic vertebrae – posteriorly Ribs – laterally Ribs – laterally Sternum and costal cartilage – anteriorlySternum and costal cartilage – anteriorly

Protects thoracic organsProtects thoracic organs Supports shoulder girdle and upper Supports shoulder girdle and upper

limbslimbs Provides attachment sites for musclesProvides attachment sites for muscles

The Bony ThoraxThe Bony Thorax

Figure 7.19a

The Bony ThoraxThe Bony Thorax

Figure 7.19b

SternumSternum

Formed from three parts :Formed from three parts : ManubriumManubrium – superior part – superior part

Articulates with medial end of claviclesArticulates with medial end of clavicles BodyBody – bulk of sternum – bulk of sternum

Sides are notched as articulations for costal Sides are notched as articulations for costal cartilage of ribs 2–7cartilage of ribs 2–7

Xiphoid processXiphoid process – inferior end of – inferior end of sternumsternum

Ossifies around age 40Ossifies around age 40

SternumSternum

Anatomical landmarksAnatomical landmarks Jugular notchJugular notch

Central indentation at superior border of the Central indentation at superior border of the manubriummanubrium

Sternal angleSternal angle A horizontal ridge where the manubrium A horizontal ridge where the manubrium

joins the bodyjoins the body

RibsRibs

All ribs attach to vertebral column All ribs attach to vertebral column posteriorlyposteriorly True ribsTrue ribs - superior seven pairs of ribs - superior seven pairs of ribs

Attach to sternum by costal cartilageAttach to sternum by costal cartilage False ribsFalse ribs – inferior five pairs of – inferior five pairs of

ribs ,attatch indirectly to the sternumribs ,attatch indirectly to the sternum

floatingfloating ribsribs ribs 11–12 are short ribs 11–12 are short and free anteriuorly.and free anteriuorly.

RibsRibs

Figure 7.20a

RibsRibs

Figure 7.20b

Disorders of the Axial Disorders of the Axial SkeletonSkeleton

Abnormal spinal curvaturesAbnormal spinal curvatures ScoliosisScoliosis – an abnormal lateral curvature – an abnormal lateral curvature KyphosisKyphosis – an exaggerated thoracic – an exaggerated thoracic

curvaturecurvature LordosisLordosis – an accentuated lumbar – an accentuated lumbar

curvature – “swayback” curvature – “swayback” Stenosis of the lumbar spineStenosis of the lumbar spine

A narrowing of the vertebral canalA narrowing of the vertebral canal

The Appendicular Skeleton The Appendicular Skeleton

Allows us to move and Allows us to move and manipulate objectsmanipulate objects

Includes all bones other than Includes all bones other than axial skeleton, it includes:axial skeleton, it includes: the limbs (upper & lower limbs)the limbs (upper & lower limbs) the supportive girdlesthe supportive girdles (pectoral (pectoral

&pelvic girdles)&pelvic girdles)

thth

Figure 8–1

What are the bones of What are the bones of the pectoral girdle, the pectoral girdle,

their their functions, and functions, and

features?features?

The Pectoral GirdleThe Pectoral Girdle

Also called the shoulder Also called the shoulder girdlegirdle Connects the arms to the body Connects the arms to the body Positions the shouldersPositions the shoulders Provides a base for arm movementProvides a base for arm movement


Figure 8–2a


Consists of:Consists of: 2 clavicles 2 clavicles 2 scapulae2 scapulae

Connects with the axial skeleton only Connects with the axial skeleton only at the manubrium(claviculosternal at the manubrium(claviculosternal joint)joint)

The ClaviclesThe Clavicles

Figure 8–2b, c

The ClaviclesThe Clavicles

Also called Also called collarbonescollarbones Long, S-shaped bonesLong, S-shaped bones Originate at the Originate at the manubrium (sternal manubrium (sternal

end)end) Articulate with the scapulae Articulate with the scapulae

(acromial end)(acromial end)

The ScapulaeThe Scapulae

Also called Also called shoulder bladesshoulder blades Broad, flat and triangularBroad, flat and triangular Articulate with arms Articulate with arms andand collarbone collarbone

Anatomy of The Anatomy of The scapulascapula

Figure 8–3a

What are the bones of What are the bones of the upper limbs, their the upper limbs, their

functions, and functions, and features?features?

The Upper LimbsThe Upper Limbs Arms, forearms, wrists, and handsArms, forearms, wrists, and hands

NoteNote: : arm (arm (brachiumbrachium)) = 1 bone, the = 1 bone, the humerushumerus

ANATOMY OF The ANATOMY OF The HumerusHumerus

Figure 8–4

The HumerusThe Humerus

Also called the Also called the armarm The long, upper armboneThe long, upper armbone Articulates with the pectoral girdleArticulates with the pectoral girdle

The ForearmThe Forearm

Figure 8–5

The ForearmThe Forearm

Also called the Also called the antebrachiumantebrachium

Consists of 2 long bones:Consists of 2 long bones:ulnaulna (medial) (medial)radiusradius (lateral) (lateral)

Interosseous MembraneInterosseous Membrane

A fibrous sheet provides strengthA fibrous sheet provides strength Connects lateral margin of ulnar Connects lateral margin of ulnar

shaft to radiusshaft to radius

The WristThe Wrist

Figure 8–6

The Wrist The Wrist

8 carpal bones:8 carpal bones:4 proximal carpal bones 4 proximal carpal bones 4 distal carpal bones 4 distal carpal bones allow wrist to bend and allow wrist to bend and twisttwist

Metacarpal BonesMetacarpal Bones

The 5 long bones of the The 5 long bones of the hand hand

Numbered I–V from lateral Numbered I–V from lateral (thumb) to medial(thumb) to medial

Articulate with proximal Articulate with proximal phalangesphalanges

PhalangesPhalanges of the Hands of the Hands

Pollex Pollex (thumb):(thumb):2 phalanges (proximal, 2 phalanges (proximal, distal) distal)

Fingers:Fingers:3 phalanges (proximal, 3 phalanges (proximal, middle, distal)middle, distal)

What are the bones of What are the bones of the pelvic girdle, their the pelvic girdle, their


The The PelvisPelvis

Consists of 2 Consists of 2 ossa coxaeossa coxae, , the the sacrum,sacrum, and the and the coccyxcoccyx

Stabilized by ligaments of Stabilized by ligaments of pelvic girdle, sacrum, and pelvic girdle, sacrum, and lumbar vertebraelumbar vertebrae

The Pelvic GirdleThe Pelvic Girdle

Figure 8–7

The The OSSA COXAEOSSA COXAE

Also called hipbonesAlso called hipbones Strong to bear body weight Strong to bear body weight

&stress of movement&stress of movement Each is made up of 3 fused bones:Each is made up of 3 fused bones:

iliumilium (articulates with sacrum) (articulates with sacrum) ischiumischium pubispubis

The The Acetabulum (vinegar Acetabulum (vinegar cup)cup)

Also called the Also called the hip sockethip socket Is the meeting point of the Is the meeting point of the

ilium, ischium, and pubis ilium, ischium, and pubis Articulates with head of Articulates with head of

the femur (the femur (Hip joint))Hip joint))

Marks of the PubisMarks of the Pubis Pubic symphysis:Pubic symphysis:

gap between pubic tuberclesgap between pubic tubercles padded with fibrocartilagepadded with fibrocartilage

Marks of the Ischium•Ischial tuberosity:posterior

projection you sit on• Ischeal spine,superior to the

tuberosity ,important during labour

The PelvisThe Pelvis

Figure 8–8

Divisions of the PelvisDivisions of the Pelvis

Figure 8–9

The PelvisThe Pelvis

PerineumPerineum region: region: inferior edges of true pelvisinferior edges of true pelvis forms forms pelvic outletpelvic outlet perineal muscles support organs of perineal muscles support organs of

pelvic cavitypelvic cavity

What are the structural What are the structural and functional and functional

differences between differences between the male and female the male and female

pelvis?pelvis?

Comparing the Male Comparing the Male and Female Pelvisand Female Pelvis

Female pelvis:Female pelvis:smoothersmootherlighterlighterless prominent muscle and less prominent muscle and ligament attachmentsligament attachments

Comparing the Male Comparing the Male and Female Pelvisand Female Pelvis

Figure 8–10

Pelvis Modifications Pelvis Modifications for Childbearingfor Childbearing

Enlarged pelvic outletEnlarged pelvic outlet Broad pubic angle (> 100°)Broad pubic angle (> 100°) Less curvature of sacrum and coccyxLess curvature of sacrum and coccyx Wide, circular pelvic inletWide, circular pelvic inlet Broad, low pelvisBroad, low pelvis Ilia project laterally, not upwards Ilia project laterally, not upwards

What are the bones of What are the bones of the lower limbs, their the lower limbs, their


The The Lower LimbsLower Limbs

Functions:Functions:weight bearingweight bearingmotionmotion

NoteNote: : leg = lower leg; thigh = leg = lower leg; thigh = upper leg upper leg

Bones of the Lower LimbsBones of the Lower Limbs

FemurFemur (thigh) (thigh) PatellaPatella (kneecap) (kneecap) Tibia and fibulaTibia and fibula (leg) (leg) TarsalsTarsals (ankle) (ankle) MetatarsalsMetatarsals (foot) (foot) PhalangesPhalanges (toes) (toes)

The The FemurFemur(longest, heaviest )(longest, heaviest )

Figure 8–11

The The PatellaPatella

Also called the Also called the kneecapkneecap Formed within tendon of Formed within tendon of quadriceps quadriceps

femorisfemoris

The Tibia and FibulaThe Tibia and Fibula

Figure 8–13

The The TibiaTibia Also called the Also called the shinboneshinbone Supports body weightSupports body weight Larger than fibulaLarger than fibula Medial to fibulaMedial to fibula

The Fibula• Attaches muscles of feet and toes• Smaller than tibia• Lateral to tibia

Bones of the AnkleBones of the Ankle

Talus:Talus: CalcaneusCalcaneus (heel bone): (heel bone):

transfers weight to groundtransfers weight to ground attaches Achilles tendonattaches Achilles tendon

The AnkleThe Ankle

Also called the Also called the tarsus:tarsus: consists of 7 consists of 7 tarsal tarsal

bonesbones

Figure 8–14a

Feet: Metatarsal BonesFeet: Metatarsal Bones

5 long bones of foot 5 long bones of foot Numbered I–V, medial to lateralNumbered I–V, medial to lateral Articulate with toesArticulate with toes

Feet: PhalangesFeet: Phalanges

Phalanges: Phalanges: bones of the toesbones of the toes

Hallux:Hallux: big toebig toe, 2 phalanges (distal, proximal), 2 phalanges (distal, proximal)

Other 4 toes:Other 4 toes: 3 phalanges (distal, medial, proximal)3 phalanges (distal, medial, proximal)

Feet: Feet: ArchesArches

ArchesArches transfer weight from 1 part of transfer weight from 1 part of the foot to another the foot to another

Figure 8–14b

Arches of the FootArches of the Foot

Bones are arranged to form THREE strong Bones are arranged to form THREE strong arches,arches, 2 longitudinal2 longitudinal (medial & lateral)& (medial & lateral)&

1 transverse1 transverse Ligaments & tendons help to hgold the Ligaments & tendons help to hgold the

bones firmly in the arched position but still bones firmly in the arched position but still allow a certain amount of spriginessallow a certain amount of spriginess

Week arches are referred to as flat footWeek arches are referred to as flat foot

Articulations (Joints)Articulations (Joints)

FunctionFunction

Holds bones togetherHolds bones together Allows bones to moveAllows bones to move All bones articulate with at least one All bones articulate with at least one

other bone except the hyoid.other bone except the hyoid.

Classification of jointsClassification of joints

FunctionalFunctional classification: focuses on the classification: focuses on the amount of movement (synarthrosis, amount of movement (synarthrosis, amphiarthrosis and diarthrosis)amphiarthrosis and diarthrosis)

StructuraStructural classification:based on l classification:based on whether whether FibrousFibrous, , CartilageCartilage or a or a joint joint cavitycavity separates the bony regions at separates the bony regions at the joint.the joint.

As a general rule, fibrous joints are As a general rule, fibrous joints are immovable and synovial joints are immovable and synovial joints are freely movable .freely movable .

TypesTypes SynarthrosesSynarthroses No movementsNo movements

Primarily axial Primarily axial skeletonskeleton

Bones Bones connected with connected with fibrous tissuefibrous tissue ligamentligament

Examples:Skull Examples:Skull sutures and sutures and distal distal Tibia/FibulaTibia/Fibula

TypesTypes AmphiarthrosAmphiarthros

eses Slightly Slightly

movablemovable Axial skeletonAxial skeleton Connected by Connected by

cartilagecartilage Intervertebral Intervertebral

joints, pubic joints, pubic symphysis symphysis

TypesTypes DiarthrosesDiarthroses – freely movable – freely movable

Also called synovial (fluid filled joint cavity)Also called synovial (fluid filled joint cavity) Primarily found in the limbsPrimarily found in the limbs Plane of movement depends on the jointPlane of movement depends on the joint

Synovial Joints - StructureSynovial Joints - Structure1. Articular cartilage: hyaline1. Articular cartilage: hyaline

2. Joint Cavity: space filled with lubricating 2. Joint Cavity: space filled with lubricating fluidfluid

3.Fibrous Capsule: fibrous CT lined with a 3.Fibrous Capsule: fibrous CT lined with a smooth synovial membranesmooth synovial membrane

4. Reinforcing Ligament: can be inside or 4. Reinforcing Ligament: can be inside or outside the joint capsuleoutside the joint capsule

5.Synovial Fluid: viscous and lubricating5.Synovial Fluid: viscous and lubricating

6. Bursae: fluid filled sacs ,see later6. Bursae: fluid filled sacs ,see later

7. Tendons sheath an elongated bursa that 7. Tendons sheath an elongated bursa that rapes around a tendon subjected to friction.rapes around a tendon subjected to friction.

8. Menisci: cartilaginous discs8. Menisci: cartilaginous discs

Synovial JointSynovial Joint

Types of synovial joints based Types of synovial joints based on shapeon shape

Plane(nonaxial)Plane(nonaxial)

-Slipping or gliding -Slipping or gliding movementsmovements

-Intercarpel joints are best -Intercarpel joints are best examplesexamples

Hinge joints( uniaxial)Hinge joints( uniaxial)

Angular movement is allowed in only Angular movement is allowed in only one plane like a hingeone plane like a hinge

Examples :elbow,ankle and Examples :elbow,ankle and interphalangeal jointsinterphalangeal joints

Ball-and-socket jointsBall-and-socket joints

A spherical head of one bone fits into A spherical head of one bone fits into a round socket in anothera round socket in another

These Multiaxial joints allow These Multiaxial joints allow movements in all axes including movements in all axes including rotationrotation

Shoulder and Hip are examplesShoulder and Hip are examples

BursaeBursae

Flattened fibrous sac lined with Flattened fibrous sac lined with synovial membrane with thin synovial membrane with thin synovial fluidsynovial fluid

Acts as bags of lubricant to reduce Acts as bags of lubricant to reduce friction where ligaments, muscle, friction where ligaments, muscle, skin, tendon or bones rub togetherskin, tendon or bones rub together

Disorders of jointsDisorders of joints

DislocationDislocation:Bone is forced out of its :Bone is forced out of its position,Reduction is done by experts position,Reduction is done by experts onlyonly

BursitisBursitis: example falling on the knee: example falling on the knee SprainSprain: excessive stretch on a ligament: excessive stretch on a ligament ArthritisArthritis: inflammation of joints, may be: inflammation of joints, may be -Acute: usually bacterial-Acute: usually bacterial -Chronic: Rheumatoid-Chronic: Rheumatoid ,Osteoarthritis and,Osteoarthritis and Gouty arthritisGouty arthritis

Developmental aspectsDevelopmental aspects

Long bonesLong bones are formed of Hyaline cartilage are formed of Hyaline cartilage Flat bonesFlat bones of skull are formed of fibrous of skull are formed of fibrous

membranesmembranes At At birthbirth,some fontanels still remain,some fontanels still remain By end of By end of adolescenceadolescence, the epiphysial , the epiphysial

plates are fully ossifiedplates are fully ossified Adult skullAdult skull is 1/8 & infant skull is 1/4 of the is 1/8 & infant skull is 1/4 of the

total body lengthtotal body length

At birth,craniumAt birth,cranium is huge relative to is huge relative to face,it is related to rapid growth of face,it is related to rapid growth of brainbrain

By 2By 2 years skull is 3/4 adult size years skull is 3/4 adult size By 9By 9 years,skull become nearly of years,skull become nearly of

adult sizeadult size At birthAt birth, the spine is arched (, the spine is arched (primaryprimary) )

and convex posteriorlyand convex posteriorly SecondarySecondary curvature are convex curvature are convex

anteriorly, cervical with raising the anteriorly, cervical with raising the head & lumber with start of walkinghead & lumber with start of walking

S-shaped spine in adultS-shaped spine in adult

At birthAt birth the UL ratio is 1.7 to 1 the UL ratio is 1.7 to 1 At At 1010, UL is 1 to 1, UL is 1 to 1 Bones become stronger with pull of gravity Bones become stronger with pull of gravity

&muscle contractions&muscle contractions Osteoporosis,Osteoporosis, thin and fragile bones occurs in thin and fragile bones occurs in

totally inactive persons. It occurs in half women totally inactive persons. It occurs in half women after 65 and in20% of men after70(estrogen after 65 and in20% of men after70(estrogen maintain healthy bones)maintain healthy bones)

Causes of Osteoporosis:Causes of Osteoporosis: - estrogen deficiency- estrogen deficiency - diet poor in calcium & protein- diet poor in calcium & protein - lack of vitamin D- lack of vitamin D - smoking- smoking - lack of exercise- lack of exercise - - pathologic fracture is the resultpathologic fracture is the result END of Sk. systemEND of Sk. system

Download - Anatomy of Skeletal System. SKELETAL SYSTEM COMPOSED OF: COMPOSED OF: -Bones -Bones -Cartilage -Cartilage -Joints -Joints -Ligaments -Ligaments

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