Figure 7.1a
Skull
Thoracic cage(ribs andsternum)
(a) Anterior view
Facial bonesCranium
Sacrum
Vertebralcolumn
ClavicleScapulaSternumRibHumerusVertebraRadiusUlnaCarpals
PhalangesMetacarpalsFemurPatella
TibiaFibula
TarsalsMetatarsalsPhalanges
Ch. 7 The Skeleton
Skeletal System
• Composed of bones, cartilage, joints, and ligaments
• Accounts for 20% of body mass• 30 lbs in a 160 lb person• Bones – most of skeleton• Cartilage – isolated areas – nose, parts of ribs,
joints• Ligaments – connect bones and reinforce joints• Joints – allow for motility
Axial Skeleton
• 80 bones segregated into 3 major regions• Skull, vertebral column, and thoracic cage• Forms:
1. Longitudinal axis of body2. Supports head, neck, and trunk3. Protects brain, spinal cord, and organs of the
thorax
Skull
• Body’s most complex bone structure• Formed by cranial and facial bones – 22 in all• Cranium – cranial bones• Enclose and protect the brain• Attachment sites for head and neck muscles
Skull
• Facial Bones 1. Form framework of the face2. Contain cavities for special sense organs –
sight, taste, and smell3. Provide openings for air and food passage4. Secure the teeth5. Anchor facial muscles of expression
Skull
• Bones• Most are flat bones except for mandible• firmly united by interlocking joints – sutures• Major sutures –
1. Coronal2. Sagittal3. Squamous4. lambdoid
Figure 7.2a
Bones of cranium (cranial vault)
Lambdoidsuture
Facialbones
Squamoussuture
(a) Cranial and facial divisions of the skull
Coronalsuture
Skull - Overview
• Lopsided, hallow, bony sphere• Anterior – facial bones• Rest – cranium• Cranium – divided into vault and base• Cranial vault – calvaria – forms superior, lateral, and
posterior aspects• Cranial base or floor – inferior aspect - internal bony
ridges – anterior, middle, and posterior cranial fossae• Brian fits in snuggly
Figure 7.2b
Anterior cranialfossa
Middle cranialfossa
Posterior cranialfossa
(b) Superior view of the cranial fossae
Skull - Overview
• Smaller cavities – – Middle and inferior ear– Nasal cavities and orbits
• 85 names openings – – Formina– Canals– Fissures, Etc.
• Passageway for spinal cord, blood vessels, and cranial nerves (I-XII)
Cranium
• 8 bones• 1. Frontal Bone – anterior cranium• Articulates posteriorly with paired parietal bones via – coronal
suture• Anterior part – vertical squamous part – forehead• Extends posteriorly forming superior walls of orbits and most
of anterior cranial fossa – supports frontal lobes of the brain• Subraorbital margin – pierced by supraorbital forman (notch)
which allows artery and nerve to pass to forehead• Smooth portion between orbits – glabella• Just inferior – meets nasal bones at frontonasal suture• Frontal sinuses
Figure 7.4a
(a) Anterior view Mandibular symphysis
Frontal bone
GlabllaFrontonasal suture
Supraorbital foramen(noch)Supraorbital margin
Cranium
2. Parietal Bones• 2 large bones• Curved, rectangular bones form most of the superior
and lateral aspects• Bulk of the cranial vault• 4 largest sutures where parietal bones articulate
1. Coronal suture – parietal meets frontal2. Sagittal suture – parietals meets superiorly3. Lambboid suture – parietal meets occipital posteriorly4. Squamous suture – parietal and temporal meet at lateral
aspect
Figure 7.4a
Parietal bone
Parietal bone
Cranium
3. Occipital Bone• Forms most of skulls posterior wall and base• Articulates anteriorly with paired parietal and
temporal – lambdoid and occipitomastoid sutures
• Joins sphenoid bone in cranial floor• Projection – pharyngeal tubercle
Occipitalbone
(a) External anatomy of the right side of the skull
Figure 7.5a
Cranium
3. Occipital Bone• Internally – forms walls of posterior cranial fossa –
supports cerebellum• Base – foramen magnum – through which brain
connects with spinal cord• Flanked laterally by 2 occipital condyles – aciculate with
first vertebrae – permits nodding• Hypoglossal canal – cranial nerve XII passes• External occipital protuberance – median protrusion• Other ridges and crests mark bones
Occipitalbone
(a) External anatomy of the right side of the skull
Figure 7.5a
Cranium
4. Temporal Bones – • Line inferior to parietal bones and meet them
at squamous sutures• Form inferolateral aspects of skull and part of
the cranial floor• Complicated shape – 4 major areas (regions)• Squamous, mastoid, tympanic, and petrous
(a) External anatomy of the right side of the skull
Temporal bone
Figure 7.5a
Cranium
4. Temporal Bones – • Squamous Region – abuts squamous suture• Bar like zygomatic process – meets zygomatic
bones of the face• Form zygomatic arch – projections of cheek• Mandibular fossa – receive lower jawbone –
forms temporomandibular joint
Figure 7.8
Mastoidregion
Externalacousticmeatus
Mastoidprocess
Styloid process
Tympanic region
Mandibular fossa
Zygomatic process
Squamousregion
Cranium
4. Temporal Bones – • Tympanic region – surrounds external acoustic
meatus – external ear canal• Below- needle like styloid process –
attachment for tongue and neck muscles
Figure 7.8
Mastoidregion
Externalacousticmeatus
Mastoidprocess
Styloid process
Tympanic region
Mandibular fossa
Zygomatic process
Squamousregion
Cranium
4. Temporal Bones – • Mastoid Region – mastoid process – anchoring
site for neck muscles• Stylomastoid foramen – allow cranial nerve VII
to leave skull• Middle cranial fossa – sphenoid and petrous• Supports temporal bones of brain
Carinum
4. Temporal Bones – • Several foramen - jugular vein and cranial
nerves IX, X, XI• Carotid canal – carotid artery• Foramen lacerum – closed by cartilage in living
room• Internal acoustic meatus – cranial nerves VII &
VIII
Figure 7.8
Mastoidregion
Externalacousticmeatus
Mastoidprocess
Styloid process
Tympanic region
Mandibular fossa
Zygomatic process
Squamousregion
Cranium
5. Sphenoid Bone – bat shaped• Spans width of middle cranial fossa• Central wedge – articulates with all the other
cranial bones• Central body and 3 pairs of processes
• Greater wings, lesser wings, and pterygoid processes
• With in the body – paired sphenoid sinuses
Figure 7.9a
Greaterwing
Hypophysealfossa ofsella turcica
ForamenrotundumForamenovaleForamenspinosumBody of sphenoid
Superiororbital fissure
(a) Superior view
Optic canalLesser wing
Figure 7.9b
Body of sphenoid
Greaterwing
Superiororbitalfissure
Lesserwing
Pterygoidprocess
(b) Posterior view
Cranium
6. Ethmoid Bone – complex shape• Lies between sphenoid and nasal bones• Superior surface – cribriform plates• Crista galli – triangular processes• Perpendicular plate – part of nasal septum• Lateral mass – ethmoid sinuses
Figure 7.10
Orbitalplate
Ethmoidalair cells
Perpendicularplate Middle nasal concha
Cribriformplate
Olfactoryforamina
Crista galli
Left lateral mass
Cranium
7. Sutural Bones – • Thin irregularly shaped bones with in sutures• Vary in numbers• Not in all skulls• Unknown significance
Figure 7.4b
Suturalbone
7. Sutural Bones – • Thin irregularly
shaped bones with in sutures
• Vary in numbers• Not in all skulls• Unknown
significance
Facial Bones
• 14 bones • Only mandible and vomer unpaired• Men – more elongated than women• Women – rounder and less angular
Facial Bones - Mandible
• Lower jawbone• Longest and strongest• Forms chin• 2 upright rami – meet body posterior at
mandibular angle• Top groove – notch• Body – anchors lower teeth
– Alveolar margin – contains sockets where teeth are embedded
Figure 7.11a
Coronoidprocess
Mandibular foramen
Mentalforamen
Mandibularangle
Ramusofmandible
Mandibularcondyle
Mandibular notch
Mandibular fossaof temporal bone
Body of mandible
Alveolarmargin
(a) Mandible, right lateral view
Temporomandibularjoint
Facial Bones – Maxillary Bones
• Maxillae• Fused medially • Form upper jaw and central portion of face• Upper teeth – alveolar margins
Figure 7.11b
Frontal process
Articulates withfrontal bone
Anterior nasalspine
Infraorbitalforamen
Alveolarmargin
(b) Maxilla, right lateral view
Orbitalsurface
Zygomaticprocess(cut)
Figure 7.4a
Zygomatic bone
(a) Anterior view
Irregularly shapedCheek bone and part of inferolateral margins of orbits
Facial Bones – Nasal Bones
• Thin, rectangular, bridge of nose• Attach to cartilage of external nose
Figure 7.5a
Nasal bone
Thin, rectangular, bridge of noseAttach to cartilage of external nose
Facial Bones – Nasal Bones
Figure 7.4a
Lacrimal bone
(a) Anterior view
Delicate, fingernail shapedContribute to medial walls of each orbitDeep grove – lacrimal fossa – allows tears to drain
Facial Bones – Lacrimal Bones
Facial Bones – Palatine Bones
• 2 bony plates – horizontal and perpendicular• 3 processes – pyramidal, sphenoidal, and
orbital• Horizontal plate – hard palate• Perpendicular – walls of nasal cavity and small
part of orbits
Figure 7.6a
Incisive fossa
Median palatine sutureIntermaxillary suture
Infraorbital foramenMaxilla
Sphenoid bone(greater wing)
Maxilla(palatine process)
Hardpalate
(a) Inferior view of the skull (mandible removed)
Palatine bone(horizontal plate)
Figure 7.6a
Incisive fossa
Median palatine sutureIntermaxillary suture
Infraorbital foramenMaxilla
Sphenoid bone(greater wing)
Maxilla(palatine process)
Hardpalate
Vomer
(a) Inferior view of the skull (mandible removed)
Palatine bone(horizontal plate)
• Slender, plow shaped
• In nasal cavity and small part of orbit
Figure 7.14a
Inferior nasalconcha
Nasal bone
Thin, curved bones in nasal cavity Wall of nasal cavity
Inferior Nasal Conchae
Hyoid Bone
• Not really part of skull
• U shaped• Inferior to mandible
in anterior neck• Does not articulate
directly with any other bone
• Horseshoe shaped
The Vertebral Column
• Spine or spinal column• 26 irregular bones connected in a flexible
curved shape• Skull pelvis• Infant – 33 bones • Adult – 9 fuse 24 bones
Figure 7.16
Cervical curvature (concave)7 vertebrae, C1–C7
Thoracic curvature(convex)12 vertebrae,T1–T12
Lumbar curvature(concave)5 vertebrae, L1–L5
Sacral curvature(convex)5 fused vertebrae sacrum
Coccyx4 fused vertebrae
Anterior view Right lateral view
Spinousprocess
Transverseprocesses
Intervertebraldiscs
Intervertebralforamen
C1
The Vertebral Column
• Regions – • ~ 70 cm long (28 inches)• 5 major regions
1. Cervical region (7)2. Thoracic region (12)3. Lumbar region (5)4. Sacrum5. coccyx
The Vertebral Column
• Curvatures - • cervical and lumbar curvatures – concave
posteriorly• Thoracic and sacral – convex posteriorly
Figure 7.16
Cervical curvature (concave)7 vertebrae, C1–C7
Thoracic curvature(convex)12 vertebrae,T1–T12
Lumbar curvature(concave)5 vertebrae, L1–L5
Sacral curvature(convex)5 fused vertebrae sacrum
Coccyx4 fused vertebrae
Anterior view Right lateral view
Spinousprocess
Transverseprocesses
Intervertebraldiscs
Intervertebralforamen
C1
Abnormal Spinal Curvatures
• some present at birth• Others disease, poor posture, unequal muscle pull1. Scoliosis – “twisted disease” abnormal lateral curvature in the
thoracic region– Treated with braces or surgically
2. Kyphosis – hunchback– Dorsally exaggerate thoracic curvature– Common in elderly or from tuberculosis of spine, rickets, or
osteomalacia
3. Lordosis – swayback, accentuated lumbar curvature– Spinal tuberculosis or osteomalacia– Common in people with large belles, pregnant women
Ligaments
• Elaborate system of cable like supports• Strap like ligaments• Major – anterior and posterior longitudinal
ligaments• Run down back and front surfaces of
vertebrae• Posterior – prevents hyperextension
Intervertebral Discs
• Cushion like pad• 2 parts – inner gelatinous nucleus pulposus –
rubber ball – gives elasticity and compressibility
• Surrounded by – anucleus fibrosus – limits expansion when spine is compressed
• Woven strap• Withstands twisting and tension
Figure 7.17c
Vertebral spinous process(posterior aspect of vertebra)
Spinal nerve root
Anulus fibrosusof disc
Herniated portionof disc
Nucleuspulposusof disc
Spinal cord
(c) Superior view of a herniated intervertebral disc
Transverseprocess
Figure 7.17a
Supraspinous ligamentIntervertebraldisc
Anteriorlongitudinalligament
Intervertebral foramen
Posterior longitudinalligament
Anulus fibrosus
Nucleus pulposus
Sectioned bodyof vertebra
Transverse process
Sectionedspinous process
Ligamentum flavum
Interspinousligament
Inferior articular process
Median section of three vertebrae, illustrating the composition of the discs and the ligaments
Intervertebral Discs
• Shock absorbers• Allow to spine to bend and flex• Thickest in lumbar region• 25 % of the height of the column• Flatten during day – slightly shorter at night• Sudden trauma – herniated disc – rupture of
anulus fibrosus and protrusion of nucleus pulposus• Treatment – heat, massage, exercise. • If not must remove protruding disc and fuse
vertebrae
Structure of Vertebral Column
• Vertebrae – body (centrum) and vertebral arch• Enclose opening – vertebral foramen• Successive vertebrae – vertebral canal = spinal cord• Vertebrae arch – pedicles and laminae• Pedicles – bony pillars on inside of arch• Laminae – flattened plates• Processes from arch – spinous process, transverse
process, superior and inferior articular arches
Regional Characteristics
• Variation among groups• Allow different functions and movements• General movements –
1. Flexion and extension – straightening of spine2. Lateral flexion – upper band right or left3. Rotation – rotation on long axis of spine
Figure 7.18
Posterior
Anterior
Lamina
Superiorarticularprocessandfacet
Transverseprocess
Pedicle
Spinousprocess
Vertebralarch
VertebralforamenBody(centrum)
Cervical Vertebrae (7)
• C1 C7• Smallest, lightest• Typical – C3 C71. Body is oval2. Except C7 – spinous process is short, projects
directly back and bifid – split at top3. Vertebrae foramens large and generally
triangular4. Transverse process contains transverse foramen
Table 7.2
Cervical Vertebrae (7)
• C7 – not bifid– Larger than others– Process visible through skin– Landmark for counting vertebrae – vertebra
prominens• 1st two – atlas and axis
– More robust– No intervertebral disc– Highly modified
Figure 7.20a
Dens of axis
Transverse ligamentof atlasC1 (atlas)
C2 (axis)
Bifid spinousprocess
Transverse processes
C7 (vertebraprominens)
(a) Cervical vertebrae
C3
Inferior articularprocess
Cervical Vertebrae (7)
• C1 – atlas – no body– No spinous processes– Ring of bone– “carries” the skull– Allow to nod yes
• C2 – axis – not as specialized– Dens – “tooth” projecting from body superiorly– Pivot for rotation– Allow head to shake no
Figure 7.19a-b
Anterior arch
Superiorarticularfacet
Transverseforamen
Posterior arch
Posteriortubercle
Anteriortubercle
Posterior
Lateralmasses
(a) Superior view of atlas (C1)
C1
Facet for dens
Transverseprocess
Lateralmasses
Transverseforamen
Posterior archPosteriortubercle
Posterior
Anterior tubercle
Anteriorarch
(b) Inferior view of atlas (C1)
Inferiorarticularfacet
C2
Posterior
Dens
(c) Superior view of axis (C2)
Inferiorarticularprocess
Body
Superiorarticularfacet
Transverseprocess
Pedicle
Lamina
Spinous process
Figure 7.19c
Thoracic Vertebrae (12)
• T1 T12• First – like C7• Last 4 – progression towards lumbar• Increase in size
Thoracic Vertebrae (12)
• Characteristics – 1. Body – heart shaped
-2 small faucets – demi facets – receive heads of ribs2. Vertebral foramen is circular3. Spinosous process – long and points downward4. Except T11 and T12 – transverse costal faucets
articulate with ribs5. Faucets in frontal plane – prevent flexion and extension
-Allows to rotate – restricted by ribs
Table 7.2
Figure 7.20b
Transverseprocess
Spinousprocess
Superior articularprocess
Transversecostal facet (fortubercle of rib)
Body
Intervertebraldisc
Inferior costalfacet (for headof rib)Inferior articularprocess
(b) Thoracic vertebrae
Lumbar Vertebrae (5)
• L1 L5• Small of back• Receives the most stress• Sturdier structure• Bodies massive and kidney shaped
Lumbar Vertebrae (5)
1. Pedicles and laminae – shorter and thicker2. Spinous process – short, flat, hatchet shaped
– project downward3. Vertebrae foramen – triangular4. Orientation of facets differs – modification
lock vertebrae together and provide stability – flexion/extension possible
Table 7.2
Figure 7.20c
Superiorarticularprocess
Transverseprocess
Spinousprocess
Intervertebraldisc
Body
Inferiorarticularprocess
(c) Lumbar vertebrae
Sacrum
• Triangular shaped• Shapes posterior wall of the pelvis• S1 S5 – five fused vertebrae• Auricular surfaces and sarcoiliac joints• Sacral promontory – bulges into pelvic cavity• 4 ridges – transverse ridges
Figure 7.21a
Coccyx
AnteriorsacralforaminaApex
Sacral promontory
Ala
Body offirstsacralvertebra
Transverseridges (sites of vertebral fusion)
(a) Anterior view
Figure 7.21b
Coccyx
Posteriorsacralforamina
Mediansacralcrest
Sacralcanal
Sacralhiatus
Body Facet ofsuperiorarticular process
Lateralsacralcrest
Auricularsurface
Ala
(b) Posterior view
Coccyx
• Tailbone• Small triangular bone• 4 (sometimes 3) vertebrae fused together• Nearly useless bone
Thoracic Cage
• Chest and bony underlying• Thoracic vertebrae, ribs, sternum, and costal
cartilages• Protective cage around vital organs (heart,
lung, etc.)• Supports girdles and upper limbs
Figure 7.22a
Intercostal spaces
Trueribs(1–7)
Falseribs(8–12)
Jugular notchClavicular notch
ManubriumSternal angleBodyXiphisternaljointXiphoidprocess
L1
Vertebra Floating ribs (11, 12)(a) Skeleton of the thoracic cage, anterior view
Sternum
Costal cartilage
Costal margin
Sternum
• Breast bone• Lies in anterior midline• Flat, ~15 cm long• Fusion of 3 bones – manubrium, body, xiphoid
process• 3 anatomical landmarks – jugular notch,
sternal angle, xiphisternal joint
Figure 7.22a
Intercostal spaces
Trueribs(1–7)
Falseribs(8–12)
Jugular notchClavicular notch
ManubriumSternal angleBodyXiphisternaljointXiphoidprocess
L1
Vertebra Floating ribs (11, 12)(a) Skeleton of the thoracic cage, anterior view
Sternum
Costal cartilage
Costal margin
Ribs
• 12 pairs• Attach posteriorly to thoracic vertebrae and
curve internally towards body surface• 7 superior ribs – attach directly to sternum – true
or vertebrosternal ribs• 5 remaining – false ribs – attach indirectly or
entirely lack sternum attachment• Ribs 8 – 10 – vertebrochondrial ribs • Ribs 11 and 12 – vertebral ribs/floating ribs – no
anterior attachment
Figure 7.23a
Transverse costal facet(for tubercle of rib) Superior costal facet
(for head of rib)
Body of vertebra
Head of rib
Intervertebral disc
Tubercle of rib
Neck of rib
Shaft Sternum
Angleof rib
Cross-sectionof rib Costal groove Costal cartilage
(a) Vertebral and sternal articulations of atypical true rib
Figure 7.23b
Spinous processArticular faceton tubercle of rib
Shaft
Ligaments
Neck of rib
Head of rib Body ofthoracicvertebra
Transversecostal facet(for tubercleof rib)
Superior costal facet(for head of rib)
(b) Superior view of the articulation between arib and a thoracic vertebra
Ribs
• Increase in length – 1 7• Decrease in length – 8 12• Bowed flat bone• Bulk shaft – transverse process of vertebrae• Head, neck, and tubercle• 1st pair flattened superiorly horizontal table
Appendicular Skeleton
• Bones of limbs and their girdles• Appended to axial skeleton• Pectoral girdles – attach to upper limbs• Pelvic girdles – secure lower limbs• Limbs – same plane – 3 major segments
connected by moveable parts
Pectoral (Shoulder) Girdle
• Clavicle and scapula• Girdle – usually signifies belt like structure – pectoral
does not• Girdles attach to upper limbs to axial skeleton and
provide attachment points for muscles• Light and allow motility1. Only clavicle attaches to axial skeleton – scapula
move freely2. Socket of shoulder – shallow and poorly reinforced,
does not restrict movement, good for flexibility, bad for stability
Clavicle - collarbones
• Slender, doublely curved bones• Cone shaped at medial sternal end• Flattened on lateral – acromial end• Anchor muscles• Braces – hold scapula and arms out laterally• Not very strong, likely to shatter • Fracture outward – protect subclavian artery• Sensitive to muscle pull• Larger and stronger in those who perform manual labor
or athletics
Figure 7.24a
ClavicleAcromio-clavicularjoint
Scapula
(a) Articulated pectoral girdle
Figure 7.24b
Acromial (lateral)end(b) Right clavicle, superior view
Posterior
Sternal (medial)end
Anterior
Scapulae
• Shoulder blades• Thin, triangular flat bones• “spade” or “Shovel” • 3 borders – superior shortest, sharpest
– Medial, Vertebral Border – parallel vertebrae– Lateral or auxiliary, border abuts armpits
• Shallow fossa – glenoid cavity• Spine – easily felt through skin• Acromion – triangular portion• Acromioclavicular joint – coracoid process – anchors biceps
muscle
Figure 7.25a
Acromion
Coracoidprocess
Suprascapular notch
Superior border
Superiorangle
Subscapularfossa
Medial border
Inferior angle
Glenoidcavity
Lateral border
(a) Right scapula, anterior aspect
Figure 7.25b
Superiorangle
Medial border
Coracoid processSuprascapular notch
Acromion
Glenoidcavityat lateralangle
Lateral border
Infraspinousfossa
Spine
(b) Right scapula, posterior aspect
Supraspinousfossa
Upper Limb – 30 bones
• Arm – upper limb – shoulder elbow• Humerous - longest, largest bone of upper limb• Articulates – scapula and radius/ulna• Head fits into glenoid cavity of scapula• Coronoid fossa & olecranon fossa – allow ulna
to move freely• Radial fossa – head of radius•
Figure 7.26a
GreatertubercleLessertubercleInter-tubercularsulcus
LateralsupracondylarridgeRadialfossaCapitulum
Head ofhumerusAnatomicalneck
Deltoidtuberosity
CoronoidfossaMedialepicondyleTrochlea
(a) Anterior view
Forearm
• 2 parallel long bones• Radius and ulna• Articulate with each other• Radioulnar joint – connected by interosseous
membrane
Figure 7.27a-b
Radialnotch ofthe ulna
OlecranonprocessTrochlearnotchCoronoidprocess Proximalradioulnarjoint
Distal radioulnarjoint
Styloid processof radius
Radius
Neck ofradius
Head ofradius
Ulnar notchof the radiusHead of ulna
Styloidprocess of ulna
InterosseousmembraneUlna
Head
Neck
Radialtuberosity
Radius
Styloidprocessof radius
(a) Anterior view (b) Posterior view
Ulna
• Slightly longer than radius forming elbow joint• 2 processes – olecranon and coronoid
separated by notch
Figure 7.27c-d
(c) Proximal portion of ulna, lateral view
Olecranon process
Trochlear notch
Coronoid process
Radial notch
View
(d) Distal ends of the radius and ulna at the wrist
Ulnar notch of radius
Headof ulna
Styloidprocess
Articulationfor scaphoid
Articulationfor lunate
Styloidprocess
View
Figure 7.26c-d
Coronoidfossa
Radius
Radialtuberosity
Head ofradius
Capitulum
Trochlea
(c) Anterior view at the elbow region
Humerus
Medialepicondyle
Coronoidprocess of ulna
UlnaRadial notch
Olecranonfossa
Ulna
Olecranonprocess
Medialepicondyle
(d) Posterior view of extended elbow
Humerus
Lateralepicondyle
Head
RadiusNeck
Radius
• Thin at proximal end – wide distally• Head – shaped like head of nail• Radial tuberosity – anchors biceps molecule• Contributes with wrist joint
- Colle’s Fracture – break in distal end of radius- Falling person – break their fall
Figure 7.27a-b
Radialnotch ofthe ulna
OlecranonprocessTrochlearnotchCoronoidprocess Proximalradioulnarjoint
Distal radioulnarjoint
Styloid processof radius
Radius
Neck ofradius
Head ofradius
Ulnar notchof the radiusHead of ulna
Styloidprocess of ulna
InterosseousmembraneUlna
Head
Neck
Radialtuberosity
Radius
Styloidprocessof radius
(a) Anterior view (b) Posterior view
Hand
• Wrist – carpus• Palm – metacarpals• Phalanges - fingers
Figure 7.28a-b
• Trapezoid• Trapezium
• Scaphoid
Phalanges
Carpals
Radius
• Proximal• Middle• Distal
• Triquetrum• Lunate
• Capitate• Hamate
• Pisiform
Metacarpals
Carpals
(b) Posterior view of left hand
Ulna
• Base• Shaft• Head
• Trapezoid• Trapezium
• Scaphoid
Carpals
(a) Anterior view of left hand
Radius
Sesamoidbones
Carpus (wrist)
• Carpals – 8 marble sized bones• 2 irregular rows of 4 bones1. Proximal row – (lateral medial)- Scaphoid “boat shaped” lunate ‘moon-
shaped” triguetrum “triangle” pisciform “pea-shaped”
2. Carpals – distal row - Trapezium “little table” trapezoid “4 sided”
capitate “head-shaped” hamate “hooked”
Figure 7.28a-b
• Trapezoid• Trapezium
• Scaphoid
Phalanges
Carpals
Radius
• Proximal• Middle• Distal
• Triquetrum• Lunate
• Capitate• Hamate
• Pisiform
Metacarpals
Carpals
(b) Posterior view of left hand
Ulna
• Base• Shaft• Head
• Trapezoid• Trapezium
• Scaphoid
Carpals
(a) Anterior view of left hand
Radius
Sesamoidbones
Carpus (wrist)
• Carpal tunnel – overuse and inflammation of tendons – swell and compress nerves in the wrist
• Pain is greatest at night• Carpal tunnel syndrome
Metacarpals (palm)
• 5 radiate from wrist• Form palm of hand• Not named – numbered 1-5• Bases – articulate with carpals• Heads – articulate with phalanges• Thumb (1) – more anterior position
Figure 7.28a-b
• Trapezoid• Trapezium
• Scaphoid
Phalanges
Carpals
Radius
• Proximal• Middle• Distal
• Triquetrum• Lunate
• Capitate• Hamate
• Pisiform
Metacarpals
Carpals
(b) Posterior view of left hand
Ulna
• Base• Shaft• Head
• Trapezoid• Trapezium
• Scaphoid
Carpals
(a) Anterior view of left hand
Radius
Sesamoidbones
Phalanges (fingers)
• Digits, fingers• 1 – 5 – thumb number 1• 3rd fingers usually longest• 14 miniature bones • Distal, middle, and proximal• Thumb – no middle bone
Figure 7.28a-b
• Trapezoid• Trapezium
• Scaphoid
Phalanges
Carpals
Radius
• Proximal• Middle• Distal
• Triquetrum• Lunate
• Capitate• Hamate
• Pisiform
Metacarpals
Carpals
(b) Posterior view of left hand
Ulna
• Base• Shaft• Head
• Trapezoid• Trapezium
• Scaphoid
Carpals
(a) Anterior view of left hand
Radius
Sesamoidbones
Pelvic (Hip) Girdle
• Attaches lower limbs• Transmits full weight of upper body• Supports visceral organs• Sparingly attached to thoracic cage• Secured to axial skeleton by ligaments• Sockets – deep, cuplike• Lacks motility of pectoral girdle• Formed by pair of hip bones – os coxae or coxal bone• 3 regions – ilium, ischium, and pubis (adults – bones fused)• Point of fusion - anetabulum
Figure 7.29
Coxalbone(os coxaeor hip bone)
llium
Sacroiliacjoint
Iliac fossa
Pubicbone
Ischium
Sacrum
Base of sacrum
Sacralpromontory
Pelvic brim
Acetabulum
Pubic crestPubic symphysis
Iliac crest
Coccyx
Pubic arch
Anterior inferioriliac spine
Anteriorsuperior iliac spine
Pubic tubercle
PLAY Animation: Rotatable pelvis
Ilium
• Large, flaring bones• Superior region of coxal bone• Body with wing like portion – ala• Iliac crests – hands on hips
Figure 7.30a
IliumAla
Anterior gluteallinePosterior gluteal linePosteriorsuperioriIiac spine
Greater sciaticnotch
Posterior inferioriliac spine
Ischial bodyIschial spineLesser sciatic notch
Ischialtuberosity
Ischium
Ischial ramus Obturator foramen
Inferiorgluteal line
Acetabulum
Pubic body
Iliac crest
Anteriorsuperioriliac spine
Anterior inferioriliac spine
Pubis
Inferior ramusof pubis
(a) Lateral view, right hip bone
Figure 7.30b
Iliac fossa
Ilium
Iliac crest
Anteriorsuperioriliac spine
Anterior inferioriliac spineArcuate line
Pubic tubercle
Superior ramusof pubis
Inferior ramusof pubis
Posteriorsuperioriliac spine
Obturatorforamen
Body ofthe ilium
Ischium
Ischial ramus
(b) Medial view, right hip bone
Auricularsurface
Ischial spineLesser sciatic notch
Greater sciatic notch
Posteriorinferioriliac spine
Articular surfaceof pubis (at pubic symphysis)
Ischium
• Posteroinferior part of hip bone• Roughly L-shaped or arc shaped• Thicker superior body• Thinner inferior ramus• 3 markings
1. Ischial spine – attachment of ligament – sacrospinous ligament
2. Lesser sciatic notch3. Ischial tuberosity
Figure 7.30a
IliumAla
Anterior gluteallinePosterior gluteal linePosteriorsuperioriIiac spine
Greater sciaticnotch
Posterior inferioriliac spine
Ischial bodyIschial spineLesser sciatic notch
Ischialtuberosity
Ischium
Ischial ramus Obturator foramen
Inferiorgluteal line
Acetabulum
Pubic body
Iliac crest
Anteriorsuperioriliac spine
Anterior inferioriliac spine
Pubis
Inferior ramusof pubis
(a) Lateral view, right hip bone
Pubis
• Pubic bone• Anterior portion of hipbone• Lies nearly horizontally – urinary bladder lies
on it• Anterior portion – thickened – pubic crest• Joined by fibrocartilage – pubis symphsis –
forms pubic arch or subpubic angle
Figure 7.30a
IliumAla
Anterior gluteallinePosterior gluteal linePosteriorsuperioriIiac spine
Greater sciaticnotch
Posterior inferioriliac spine
Ischial bodyIschial spineLesser sciatic notch
Ischialtuberosity
Ischium
Ischial ramus Obturator foramen
Inferiorgluteal line
Acetabulum
Pubic body
Iliac crest
Anteriorsuperioriliac spine
Anterior inferioriliac spine
Pubis
Inferior ramusof pubis
(a) Lateral view, right hip bone
Male vs. Female
• Female – modified for childbearing – wider, shallow, lighter, and rounder
• Must be large enough to allow infants head to pass • False (greater) pelvis and true (lesser) pelvis1. False bound by alea of ilia – really part of abdomen –
helps support viscera2. True pelvis – region inferior to brim that is surrounded
by bone – deep bowl containing pelvic organs- Pelvic inlet – pelvic brim – labor – head enter inlet first- Then pelvic outlet
Comparison of Male and Female PelvesCharacteristic Female Male
Bone thickness Lighter, thinner, and smoother
Heavier, thicker, and more prominent markings
Pubic arch/angle 80˚– 90˚ 50˚– 60˚
Acetabula Small; farther apart Large; closer together
Sacrum Wider, shorter; sacral curvature is accentuated
Narrow, longer; sacral promontory more ventral
Coccyx More movable; straighter Less movable; curves ventrally
Lower Limb
• Carry entire weight of body• Subjected to exceptional force• Thicker and stronger than upper limbs
Thigh - Femur
• Single bone of thigh• Largest, longest, strongest bone in body• Clothed in bulky muscles• Articulates with hip bone and knee• Ball like head, neck, and shaft• Ends in wheel like lateral and medial condyles –
articulate with tibia• Patella – triangular seasmoid bone – enclosed in
quadriceps – tendon secures thigh muscles to tibia
Figure 7.31
Neck Foveacapitis
Greatertrochanter
Inter-trochantericcrest
Head
Intertrochantericline
Lesser trochanter
Gluteal tuberosity
Linea aspera
Lateralcondyle
LateralepicondyleIntercondylar fossa
Medial andlateral supra-condylar lines
Medial condyle
Medialepicondyle
Adductortubercle
Anterior view Posterior view(b) Femur (thigh bone)
Lateral epicondyle
Patellar surface
Posterior
Facet formedialcondyleof femur
Facet for lateralcondyle of femur
Surface forpatellarligament
ApexAnterior
(a) Patella (kneecap)
Leg
• 2 parallel bones – tibia and fibia• Connected by interosseous membrane
Figure 7.32a
Medial condyle
Articular surface
Tibial tuberosity
Interosseous membrane
Anterior border
Tibia
Medial malleolus
Intercondylar eminence
Proximal tibiofibularjoint
Distal tibiofibularjoint
Lateral malleolus
Lateral condyle
Fibula
Head
(a) Anterior view
Tibia
• Receives weight of body from femur• 2nd only to femur in size and strength
Figure 7.32a
Medial condyle
Articular surface
Tibial tuberosity
Interosseous membrane
Anterior border
Tibia
Medial malleolus
Intercondylar eminence
Proximal tibiofibularjoint
Distal tibiofibularjoint
Lateral malleolus
Lateral condyle
Fibula
Head
(a) Anterior view
Fibula
• Stick like bone with slightly expanded ends
Figure 7.32a
Medial condyle
Articular surface
Tibial tuberosity
Interosseous membrane
Anterior border
Tibia
Medial malleolus
Intercondylar eminence
Proximal tibiofibularjoint
Distal tibiofibularjoint
Lateral malleolus
Lateral condyle
Fibula
Head
(a) Anterior view
Foot
• Tarsus, metatarsus, and phalanges• 2 functions – supports body weight and acts a
lever to propel body forward
Figure 7.33a
Medialcuneiform
Phalanges
Metatarsals
TarsalsNavicular
Intermediatecuneiform
Talus
Calcaneus(a) Superior view
Cuboid
Lateralcuneiform
Proximal54321
Middle
Distal
Trochleaof talus
Figure 7.33b
Facet formedialmalleolus
Calcanealtuberosity(b) Medial view
Intermediatecuneiform Sustentac-
ulum tali(talar shelf)
Talus
Navicular
First metatarsal
Medialcuneiform
Calcaneus
PLAY Animation: Rotatable bones of the foot
Figure 7.33a
Medialcuneiform
TarsalsNavicular
Intermediatecuneiform
Talus
Calcaneus(a) Superior view
Cuboid
Lateralcuneiform
54321
Trochleaof talus
7 bones – tarsals2 largest – talus and calcaneous
Figure 7.33a
Metatarsals54321
5 small bones1-5, big toe - #1
Figure 7.33a
Phalanges
Proximal54321
Middle
Distal
14 bones – smaller than hands3 on each digit except great toe (hallux)Only 2 – proximal and distal
Arch
• 3 arches – 2 longitudinal – medial and lateral and 1 transverse
• Maintained by bones, ligament, and pull of tendons• Provide springiness• Makes running and walking more economical in terms of
energy use• Medial – well above ground• Lateral – very low• Transverse – other way• Standing immobile – long periods – strain on tendons and
ligaments – flat feet
Figure 7.34a
Medial longitudinalarch
Transverse arch
Laterallongitudinal arch
(a) Lateral aspect of right foot