Transcript Appendicular Skeleton

WHERE AM I?
Online Anatomy Module 1
INTRO & TERMS
CELL
EPITHELIUM
CONNECTIVE TISSUE
MUSCLE
NERVOUS SYSTEM
AXIAL SKELETON
APPENDICULAR SKELETON
MUSCLES
EMBRYOLOGY
SKULL
VERTEBRAL
COLUMN
RIBS
SKELETON: Divisions
PECTORAL GIRDLE
LIMB BONES
PELVIC GIRDLE
LIMB BONES
Marieb Fig 5.6, p 121
2 SKELETONS
APPENDICULAR
SKELETON
PECTORAL GIRDLE
CLAVICLE (Collar
bone) omitted
LIMB BONES upper
PELVIC GIRDLE
LIMB BONES lower
appendicular skeleton hangs on the axial
PECTORAL GIRDLE
The pectoral girdle is not a 19thcentury corset for the upper chest
On each side, it is a pair of bones that
allows the arm to be fastened to the
body, but to have an amazing range of
movements & uses
The arm is used for: swinging, crawling,
reaching, pulling, throwing, twisting; &
for positioning, orienting, stabilizing &
controlling all that the hand does
The bones of the pectoral girdle are
the shoulder-blades & the collar-bones
PECTORAL GIRDLE
The bones of the pectoral girdle are the
shoulder-blades & the collar bones
SCAPULA or SHOULDER-BLADE
CLAVICLE or COLLAR-BONE
SCAPULA
The SCAPULA is a peculiarly-shaped bone,
with many surfaces, edges and
protuberances for muscles (& ligaments) to
attach. These are needed to control the arm
directly, but also to position and stabilize the
scapula for whatever the arm is doing
The scapula is a highly mobile bone
The arm is used for: swinging, crawling,
reaching, pulling, throwing, twisting, etc; & for
positioning, orienting, stabilizing & controlling
all that the hand does
SCAPULA Shoulder-blade
PECTORAL
GIRDLE
The scapula is the major part of the
pectoral girdle & lies posteriorly
The scapula is a shallow dish, with the
concave side facing anteriorly, as it fits
over the muscles & ribs of the back
SCAPULA: Terminology
Acromion process
Coracoid process
Spine
Vertebral
margin
Inferior angle
Glenoid fossa
Needless to say, each side and
angle has a name. Here are
enough to be going on with.
SCAPULA: Parts I
The SPINE rises and thickens from
the medial edge going laterally,
forming a triangular ridge ending in
a protuberance termed the
ACROMION
Spine
The spine defines
territories above & below
it, into which muscles fit
Acromion = Acromion process
SCAPULA: Parts II
ACROMION PROCESS
improves the angle of action of the deltoid
muscle pulling the arm away from the body, &
anchors the lateral end of the clavicle
Medial/Vertebral
margin
Spine
Coracoid
process
Lies by the spines of
vertebrae from which
muscles attach to it
Glenoid fossa
SCAPULA: Parts III
Acromion process
CORACOID PROCESS
Anterior beak to improve
angle of biceps muscle
Spine
Medial/Vertebral
margin
h
u
m
e
r
u
s
GLENOID FOSSA
Shallow socket
for head of the
humerus
SCAPULA: Parts IV
Viewed from side
Acromion process
Coracoid process
Anterior beak to improve
angle of pull of hbiceps muscle
Spine
Glenoid fossa
u
m
e
r
u
s
SCAPULA & CLAVICLE
The SCAPULA is a peculiarly-shaped bone,
with many surfaces, edges and
protuberances for muscles (& ligaments) to
attach. These are need to control the arm,
but also to position and stabilize the scapula
for whatever the arm is doing
The scapula is a highly mobile bone
The arm is used for: swinging, reaching, pulling,
throwing, twisting; & for positioning, orienting,
stabilizing & controlling all that the hand does
The CLAVICLE is the strut that: holds the
shoulder out away from the trunk; absorbs
shock; fastens appendicular to axial
skeleton (at the sterno-clavicular joint) ; &
anchors several muscles & ligaments
CLAVICLE
The arm is used for: swinging, crawling, reaching,
pulling, throwing, twisting; & for positioning, orienting,
stabilizing & controlling all that the hand does
The CLAVICLE is the strut/brace that:
holds the shoulder out, away from the
trunk;
absorbs shock; &
fastens appendicular to axial skeleton
(at the sterno-clavicular joint)
& anchors several muscles & ligaments
Connections between axial & appendicular
skeletons I Sterno-clavicular joint
CLAVICLE
Sterno-clavicular joint
Sternum
S
T
E
R
N
U
M
SCAPULA
rotated
unnaturally
Connections between axial & appendicular
skeletons I Sterno-clavicular joint
CLAVICLE
Jugular notch
Manubrium
Sternum body
S
T
E
R
N
U
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Acromio-clavicular joint
Scapula has no
other joints, Hence
NO joint with axial
skeleton.
SCAPULA
rotated
unnaturally
Sterno-clavicular joint
Marieb Fig 5.20, p 133
CLAVICLE Left versus Right I
The clavicle has a lumpy sternal end & a
blade-like acromial end
The upper surface is smoother* than the
inferior one, because ligaments etc come
from below to attach to tuberosities
The clavicle is a pulled-out S-shape
Use these three features to ID left from
right thus:
“Smooth” - feel on yourself
CLAVICLE Left versus Right II
1 Place the clavicle on your chest with the
lumpy end at your breast-bone
2 Try on right & left sides to make the first
curvature going outward from the
breast-bone face forward
Front
Back
3 If the upper surface is not the smoother
one, move the clavicle (keeping
orientations 1 & 2) to the other side
It should now be identifiable as Rt or Lft
Connections between axial & appendicular
skeletons II Sacro-iliac joint
SACRUM of axial is wedged into
the hip bones of the appendicular
pelvic girdle
For stability & the transmission of
load via the hip bones to the legs
Sacro-iliac joint
Marieb Fig 5.18, p 132
COMMON BONE TERMS
PROCESS
Protuberance
Tuberosity
small bump
Spine
Margin
Border
Edge
Angle
Spine
Head
FOSSA
Shallow
depression
COMMON BONE TERMS
PROCESS has become an overused word
In anatomy, as noun, it means something that sticks out
or protrudes from a cell, from a bone, or from a soft
organ
In anatomy, as noun, process still also means the
way in which something occurs - the process of
cell division, the process of shrinking, of winking
To give slow-witted politicians more time to think, the
last example has been horribly extended by their
speech-writers - for example, ‘deciding’ is a noun and
does not need to be the ‘decision-making process’.
Thus, “deciding that won’t be easy” , “wine-making is
fun” are natural & correct English
HUMERUS
Viewed from behind
Is the single bone of the ARM
Proximally, it articulates with
the scapula at the shoulder
Distally, it articulates with two
bones of the forearm at elbow joint
It has specially shaped surfaces
at the elbow to allow the ulna &
radius their movements
At the elbow, it has depressions
engaging processes of the ulna
to limit its movement
It has several tuberosities and much
surface , including epicondyles,
for the attachment of muscles
HUMERUS I
Viewed from front
HEAD
Deltoid
tuberosity
Coronoid
Fossa
Lateral
Epicondyle
Capitulum
Medial
Epicondyle
Trochlea
HUMERUS II
Viewed from behind
HEAD
Deltoid
tuberosity
Olecranon
Fossa
Medial
Epicondyle
Trochlea
Lateral
Epicondyle
HUMERUS Right versus Left
1 On yourself, place the rounded head
of the humerus at either shoulder
2 Turn the head so that it faces
medially (inward) at that shoulder
At the elbow end, look for the
shallow coronoid fossa on
one side & the deeper
olecranon fossa on the other
3 Keeping orientations 1 & 2, move
the humerus to the side that has the
deep olecranon fossa facing posteriorly
As one extends the elbow, the olecranon
process of the ulna locks into the fossa on
the humerus, preventing hyperextension
DISTAL HUMERUS
Viewed from front
Trochlear is a noun,
not an adjective
The Trochlear is a
spool-like rolling
surface for the ulna
The Capitulum is a little sphere-like
structure: a surface for rotation
The Capitulum matches a dimple in the
symmetrical head of the radius bone
For the name, remember that capital
punishment used often to include beheading
RADIUS I Viewed from in front
Head
Neck
Radial tuberosity
Styloid process
Articular surface for
wrist/carpal bones
RADIUS II Viewed from in front
Head
Neck
Radial tuberosity
Sharp edge - Interosseous
border/margin
Concave surface space for muscles
Feel for yourself: the back of
the forearm is bony, the front,
squishy
Styloid process
Articular surface for
wrist/carpal bones
RADIUS: Right versus Left
Head lies at
elbow end
Radius lies
laterally to ulna
Sharp edge faces
medially towards ulna
Concave surface space for muscles faces forward
Styloid process sort-of points
laterally
RADIUS & ULNA: Cautions
Head
Styloid process
The head of the ulna is
at the wrist end
The ulna also has a styloid
process. The two help hold
the carpal bones in place.
ULNA I
Viewed from in front
Radial notch
Olecranon
Palpable at the back of
the elbow, when you
flex & extend it
Caution - on the ulna !
Coronoid process
Ulnar head
Styloid process
ULNA II
Viewed from in front
Radial notch
Olecranon
Palpable at the back of
the elbow, when you
flex & extend it
Caution - on the ulna !
Coronoid process
Head of ulna
Ulnar head
The bump lying laterally on
the back of your wrist, when
it is pronated (palm down)
Styloid process
ULNA III
Olecranon
Coronoid process
Radial notch
allows the radius to rotate
against the ulna for
supination-pronation
movements
Interosseous margin
Concave surface space for muscles
for strong fibrous attachment
to the radius
Head
Styloid process
ULNA IV
Olecranon
Viewed from lateral side
Radial notch
allows the radius to rotate
against the ulna for supinationpronation movements
Coronoid process
a ligament holds the radius
in place
The elbow end of the ulna is
distinctive, with its hook-like
olecranon process for raking in the
chips at the neolithic gaming table
HUMERUS
Viewed from behind
It has specially shaped surfaces
at the elbow to allow the ulna &
radius their movements
At the elbow, it has depressions
engaging processes of the ulna to
limit its movement - behind, the
Olecranon fossa
takes olecranon of ulna
to limit extension of the elbow
Back to the forearm
Right FOREARM BONES
RADIUS
ULNA
RADIUS
on thumb
side
ULNA on littlefinger side
A relation kept during
pronation
ANTERIOR Right FOREARM: Radius & Ulna
SUPINATED
Thumb lateral
Radius rotates
on two radioulnar joints
Two bones are
held together by
ligaments & the
interosseous
membrane
PRONATED
Thumb medial
ULNA: Right versus Left
Olecranon is at
elbow end
Ulna lies medially
to radius
Radial notch faces
laterally toward radius
Sharp edge faces
laterally towards radius
Concave surface - space for
muscles - faces forward
Styloid process sort-of points
medially
Rt
U
LIMB
Anterior
RE-ASSEMBLY
surfaces
Head
HUMERUS
Capitulum
RADIUS
Thumb
ULNA
WRIST & HAND III
This is a view of the DORSUM (back) of the hand.
The other is the PALMAR (palm) side
Head of ulna
Little finger/ Pinky
Ring finger
Middle finger
Thumb
Index finger/
Forefinger
WRIST & HAND I
Digits
CAUTION
One thinks of the wrist as
what one grips on someone,
using one’s whole hand
Knuckles
Head of ulna
However, the wrist bones carpals - are only those that
lie under two fingers’ width
just distal to the end of the
ulna
HAND II: BONES
Phalangeal bones
Metacarpal bones
8 Carpal (wrist) bones
HAND II: BONES
Phalanges (Phalangeal
bones)
3 per finger
Terminal
Distal
Middle
Proximal
2 for the thumb
Proximal
V IV III II
I
Terminal
Metacarpal bones
8 Carpal (wrist) bones
WRIST & HAND II
Knuckles of the fist are
the heads of the
metacarpals
However, the wrist bones - carpals
- are only those that lie under two
fingers’ width just distal to the end
of the ulna
Carpal bones
Head of ulna
But the carpal bones articulate with the
radius: wrist is the radio-carpal joint
BROKEN ‘WRIST’
is a term to arouse caution
The carpal bones articulate with the radius:
wrist is the radio-carpal joint, so falling on
the hand may break the distal radius
However, the wrist bones - carpals
- are only those that lie under two
fingers’ width just distal to the end
of the ulna
Carpal bones
And one bone in particular of these
true wrist ones is sometimes fractured
MAINLY SPONGY BONE LOSS causes fractures in
1 Bones that are mostly spongy, e.g. vertebra
compression fracture
2 Spongy part of long bones where leverage
“Wrist” end
concentrates loading
of radius
“Hip” fracture at
neck of femur
from falling
on the hand
WRIST FOR COMMUNICATION
Passing through the wrist are:
Arteries
Veins
Nerves
Tendons to flex
Tendons to extend
All critical &
vunerable, &
with little
muscle or fat
to protect
them
Some protection comes from running
many structures on the palmar side
Some of the carpal bones create a
tunnel for more protection
LEFT CARPAL TUNNEL Schematic cross-section
Ulnar artery
Flexor retinaculum - sheet of fibrous
tissue roofing in the tunnel
Median nerve
Ulnar nerve
Tendons to flex
CARPAL BONES
Tendons to extend
outside tunnel, on
dorsal side of wrist
lubricated spaces/compartments for structures to glide in
Discomfort of C-T syndrome from compromised median nerve
RADIAL ARTERY: Pulse
Concave surface - space for
muscles - faces forward &
Radius lies
laterally to ulna
also protects vessels,
e.g., radial artery
Close to the wrist, where the
muscles thin & give way to
tendons, the pulse can be
felt by pressing the artery
against the bone with the
finger tips
BRACHIAL ARTERY: Pulse
Brachial refers to the arm
Humerus
The brachial artery lies protected on
the medial side of the humerus
Close to the elbow, where the
muscles thin, the pulse can be felt by
pressing the brachial artery against
the humerus, or listened for with a
stethoscope
LOWER APPENDICULAR SKELETON
Lower appendicular skeleton supports
the axial skeleton and upper body &
provides locomotion & other activities
It comprises the lower LIMB BONES &
the PELVIC GIRDLE stabilizing them
& connecting with the axial skeleton
The connection is secured by wedging
the axial sacrum between the hip
bones to create the bony pelvis
SACRUM
ILIUM
LOWER APPENDICULAR SKELETON
Lower appendicular skeleton supports
the axial skeleton upper body & provides
locomotion & other activities
It comprises the lower LIMB BONES &
the PELVIC GIRDLE stabilizing them
& connecting with the axial skeleton
The connection is secured by wedging
the axial sacrum between the hip
bones to create the bony pelvis
PELVIC GIRDLE
HIP BONES
Ilium Ischium Pubic bone
Connections between axial & appendicular
skeletons II Sacro-iliac joint
SACRUM of axial is wedged into
the hip bones of the appendicular
pelvic girdle
For stability & the transmission of
load via the hip bones to the legs
Marieb Fig 5.18, p 132
PELVIS
Viewed from in front
Is an assembly of the axial sacrum & two
SACRUM
threesomes - hip bones
The three bones are fused
together, but there are three
pelvic joints: two sacro-iliac
& one pubic symphysis
ILIUM
The pelvis protects the pelvic organs,
but has four openings, two large
The pelvis is a stable device for transferring
axial load to the legs at the hip joints
The hip joints allow the legs freedom of
movement
think gymnasts & ballet
Hip has much surface , including
crests, for the attachment of muscles
Anterior view
HIP JOINT
SACRUM
ILIUM
Acetabulum - socket for balllike head of femur/ thigh bone
This is a deep dislocationresistant ball-&-socket joint,
unlike the shoulder joint
PELVIS: Lines of sight
In general, some of the views of bones
used here are a little different from those
in the textbook in order to add to your
ideas on the pieces of the skeleton
View from above - Superior
ILIUM
View from in front & above
Most of Marieb’s Figs
View from in front - Anterior
Anterior view
PELVIC GIRDLE + SACRUM
Two hip bones are fused assemblages of three bones each.
They have the sacrum wedged between them behind &
fasten at the front by a fibrocartilaginous joint - symphysis
Sacroiliac joint
SACRUM
ILIUM
Ischium
Pubic symphysis
Pubic bone
ILIUM is the
major bone
PELVIC GIRDLE + SACRUM II
Anterior view
SACRUM
ILIUM
Obturator foramen - hole
defined by
Ischium below
Pubic bone above
Acetabulum
Anterior
view
OBTURATOR FORAMEN
SACRUM
ILIUM
Superior pubic ramus
Obturator foramen
Acetabulum
Inferior pubic ramus
Ischial tuberosity
Ischial ramus
Ramus (L) - a branch, bough
Anterior view
OBTURATOR FORAMEN II
NOTE on 1 SIDE
Two pubic rami, one
ischial ramus
Lower ramus has a
join halfway along
Unseen that the
ischium is larger than
the pubic bone
SACRUM
Superior pubic ramus
Obturator foramen
Ischial tuberosity
Inferior pubic ramus
Ischial ramus
Lateral view HIP/COXAL BONES = ONE OS COXA
HIP BONES
Ilium Ischium Pubic bone
ILIUM
Acetabulum
Ilium
Ischium
Lines of fusion of
3 bones during
childhood
Pubic bone
Obturator foramen
HIP/COXAL BONES = ONE OS COXA
CAUTION - Ask
When the term ‘hip bones’
is used, is the reference to:
ILIUM
the two composite hip bones
of each side?
the three bones making
up one hip bone?
Ilium
the six bones making up
both hip bones?
Ask
Ischium
Pubic bone
SUB-PUBIC ANGLE
SACRUM
ILIUM
Obturator-foramen shape
Sub-pubic angle (Pubic arch)
is one of many variables between female & male
pelves, aimed at having the female pelvis suited for
childbirth, as well as the other pelvic functions
ISCHIUM I
Lateral view
Anterior view
SACRUM
ILIUM
ILIUM
Sciatic
notch
Ischial ramus
Ischial tuberosity
what one sits on
Ischial tuberosity
PELVIS & ISCHIUM II
Superior view
SACRUM
Mid-pelvic diameter
Ischial spines create
a hazardous constriction in the pelvic (birth) canal
Please don’t squeeze my head Superior view
Before reaching the ischial tuberosities, etc, of the pelvic
outlet, the baby’s head has to enter the pelvic inlet
Sacral promontory
One of its critical dimensions is the
INLET between the sacral promontory
& the upper margin of the pubis
SACRUM
The sacral promontory & the
lower edge of the pubis can
be felt via the vagina for
prior warning of trouble
WORKING PELVIS
Despite the number of views of
the pelvis that we have seen
ILIUM
already, one more - the medial ILIUM view from
SACRUM Medial
is needed to understand a
the midline looking
working pelvis
laterally
The empty-appearing black
Sciatic
spaces shown within the
notch
contours of the pelvis are
occupied by many muscles &
ligaments
Ischial spine
Some holes also let nerves & vessels pass out
Although, for diagrams, the pelvis is presented aligned
with the screen or page margins, in life it is tilted in the
body in the sagittal plane
HIP/COXAL BONE
Medial view
from the midline
looking laterally
Iliac crest
(felt at the ‘hip’)
SACRUM
ILIUM
ILIUM
Sciatic
notch
Pubic symphisis
Ischial spine
Ischial tuberosity
Obturator foramen
PELVIS IN POSITION
The pelvis protects the
pelvic organs, but has four
openings, two large
Abdominal cavity
Pelvic inlet
boundary
between cavities
At the top, it is freely open
to the abdominal cavity
Pubic symphysis
ILIUM
Pelvic cavity
Underneath, the narrower
opening is covered in by the
muscles of the pelvic floor
PELVIS IN POSITION
Note the axis curves
going through the pelvis
The upper direction
is
taken as the fetus grows
into abdominal territory
At birth, the head must
make several turns &
twists to follow the axis
down
Pelvic inlet
Abdominal cavity
ILIUM
Pelvic cavity
Pubic symphysis
Pelvic axis
PELVIS: Female versus Male
We have seen just about enough views to list some of
the differences. So far, the pelvis shown has not
really been sexually differentiated.
SACRU
M
FEMALE
More lightly built
Pelvis wider & more
shallow
Obturator foramen oval
Sub-pubic angle wide
(greater than 800)
Shorter, more curved
sacrum
Unseen here:
pelvic inlet, oval;
outlet, relatively large
PELVIS: Female versus Male
FEMALE
Anterior
view
More lightly built
Pelvis wider & more
shallow
Obturator foramen oval
Sub-pubic angle wide
(greater than 800)
Shorter, more curved
sacrum
Unseen here:
pelvic inlet, oval;
outlet, relatively large
Marieb Fig 5.23, p.137
PELVIS: Male versus Female
MALE
Anterior
view
More heavily built
Pelvis deep
Obturator foramen round
Sub-pubic angle narrow
(less than 800)
Longer, straighter sacrum
Unseen: pelvic inlet, heart-shaped;
outlet, relatively small
PELVIS: Female versus Male
FEMALE
More lightly built
Pelvis wider & more shallow
Sub-pubic angle wide
(greater than 800)
MALE
Obturator foramen round
Longer, straighter sacrum
COXAL BONE: Right versus Left I
Iliac crest
(felt at the ‘hip’)
ILIUM
ILIUM
Acetabulum (on lateral side)
SACRUM
will be
absent
Pubic symphisis
For lab ID of one hip bone
Place the bone on yourself with: the iliac crest superior,
the acetabulum facing outward, and bone tilted so that
the rough pubic symphysis faces a little down, and is
right at the midline to meet its fellow of the other side
COXAL BONE: Right versus Left II
Place the bone on yourself with:
the iliac crest superior,
the acetabulum facing outward,
ILIUM
and bone tilted so that the rough pubic
symphysis faces a little down, and is
right at the midline to meet its fellow of
the other side
PELVIC ORGANS
The pelvis protects
the pelvic organs,
but has four
openings, two large
Pelvic cavity: contents
Genital/ reproductive
Urinary bladder
Ends of ureters
Rectum
Pelvic inlet
boundary
between cavities
Vessels & nerves
Abdominal cavity
ILIUM
Pelvic cavity
Pubic symphysis
Muscular pelvic floor
holds contents up.
PELVIC ORGANS: Prolapse
Pelvic cavity: contents
Genital/ reproductive
Urinary bladder
Ends of ureters
Pelvic cavity
Rectum
Vessels & nerves
Muscular pelvic floor
holds contents up.
ILIUM
If the floor is weakened by trauma,
giving birth, nerve damage, organs
can drop - prolapse; sometimes to
the point of hanging out of orifices
FEMUR I
Viewed from behind
Is the single bone of the thigh
Proximally, it articulates with
the pelvic girdle at the hip
At the hip , it has a prominent head
Distally, it articulates at the knee
with one of the two leg bones
It has specially shaped surfaces
- condyles - at the knee to roll
on the plateau of the tibia
It has several tuberosities and much
surface , including epicondyles, for the
attachment of muscles
FEMUR II
Viewed from front
Greater trochanter
Femoral head
Femoral neck
Minor trochanter
Lateral epicondyle
Medial epicondyle
FEMUR III
Femoral head
Viewed from behind
Greater trochanter
Femoral neck
Minor trochanter
Linea aspera
Lateral epicondyle
Medial condyle
Intercondylar fossa
Medial epicondyle
Lateral condyle
FEMUR IV: ID left from right Viewed from behind
Femoral head
facing in to the hip
Gluteal tuberosity
Linea aspera
facing posteriorly
Concavity for hamstring
muscles & popliteal
region to the back
Rt viewed from front
TIBIA & FIBULA I
Lateral condyle
Fibular HEAD
TIBIA
Medial condyle
Tibial tuberosity
Anterior crest
Sharp edge to be felt
down the front of the
shin bone
Lateral Malleolus
Medial Malleolus
FEMUR IV Patella
Viewed from front
The quadriceps muscles in the front of the
thigh send their tendon across the knee
joint to insert into the front of the tibia.
As the tendon passes the knee, it
includes a bone - the patella or knee-cap.
The patella, on its posterior side, has
cartilage-covered surfaces to articulate
with the anterior femur (they feel smooth)
Patella does not articulate with the tibia
Patella
The tendon continues on to anchor in the
tibial tuberosity
KNEE I
Lateral view
Anterior
Posterior
Quadriceps
muscle
Quadriceps
tendon
FEMUR
Patella
TIBIA
Popliteal space for nerves
vessels, muscles, etc
Cruciate Ligament
One of many robust ones
stabilizing the knee
The fibula does not participate
KNEE II
Anterior view
The femoral condyles roll on the flatter
condyles of the tibial plateau
Patella
F
E
M
U
R
The motion is mostly in one plane for
flexion & extension of the knee because of
the many ligaments restraining motion
However, some rotation is necessary
TIBIA
Wedge-shaped semicircular pieces of
fibrocartilage lie medially & laterally,
partially to cushion the opposing condyles.
Each is a meniscus.
The medial meniscus is held in place and
often gets torn - a “torn knee cartilage”,
with the piece(s) causing inflammation &
interfering with motion
FIBULA
Fibular HEAD
Lateral Malleolus
In the lab, the fibula is a
slender bone distinguished
by its lack of distinction at
either end
TIBIA
TIBIA & FIBULA II
Rt. viewed from front
Interosseous membrane
fastening fibula to tibia , along
with ligaments, e.g.,
Anterior tibiofibular ligament
Lateral
Malleolus
Medial Malleolus
TALUS
Rt viewed from front
TIBIA Right versus Left
TIBIA
Tibial tuberosity
Anterior crest
Sharp edge to be felt
down the front of the
shin bone
Like the femur, more
muscle is at the
back, so the
concavity should
face rearwards
Medial Malleolus
other Malleolus is
on the fibula
Big toe
FOOT I: BONES Rt foot from above
Phalangeal bones
Metatarsal bones
Tarsal / ankle bones
TALUS
CALCANEUS
heel-bone
Big toe
FOOT II: TARSAL BONES from above
Phalangeal
bones
Metatarsal
bones
Tarsal/ankle
bones
TALUS
CALCANEUS
heel-bone
Note contrasts with the
wrist bones
Two much larger bones
Only one bone - talus articulates with the tibia
& fibula
Bones held together
with strong ligaments
Bones participate in
constructing flexible
arches for walking
Marieb Fig 5.26, p. 139
7 bones instead of 8
TIBIA
FOOT III: ANKLE JOINT
Rt. viewed from front
Interosseous membrane
fastening fibula to tibia , along
with ligaments, e.g.,
Anterior tibiofibular ligament
Lateral
Malleolus
Medial Malleolus
TALUS
Rt. viewed from
medial side
The Talus spreads the load to the heel-bone and the
heads of the metatarsals to transfer to the ground, tree,
floor, mud, or wherever you live
FOOT IV: Loading
TALUS
CALCANEUS
Medial longitudinal arch of the foot. There are
also lateral longitudinal, and transverse arches
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