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Biology 231
Human Anatomy and Physiology
Chapter 8 Lecture Outline
APPENDICULAR SKELETON – shoulder and pelvic girdles and limbs; function with
muscular system in facilitating movement
PECTORAL (SHOULDER) GIRDLE – 4 bones; attach upper limbs to thorax
Clavicle (collar bone) – anterior portion of girdle; S-shaped
Parts of Clavicle:
sternal end – articulates with manubrium of sternum
acromial end – articulates with acromion of scapula
conoid tubercle
Scapula (shoulder blade) – posterior portion of girdle; doesn’t articulate with
axial skeleton; strongly attached to thorax by muscles
Parts of Scapula:
body – flat, triangular main portion
medial, lateral and superior borders
spine – prominent crest across posterior surface
acromion – process on lateral spine (point of shoulder)
articulates with clavicle
supraspinous fossa and infraspinous fossa
subscapular fossa – anterior surface
glenoid cavity – articulates with head of humerus
coracoid process
PECTORAL LIMB – 30 bones; arm, forearm, wrist, and hand
Humerus – brachium
Parts of Humerus:
head – articulates with glenoid cavity of scapula
anatomical neck – attachment of joint capsule
greater and lesser tubercles
surgical neck – frequent fracture site
body (shaft)
trochlea – articulates with ulna
coronoid fossa
olecranon fossa
capitulum – articulates with head of radius
radial fossa
medial and lateral epicondyles
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Ulna – medial antebrachium (pinky side)
Parts of Ulna:
olecranon – point of elbow; fits in olecranon fossa when elbow
extended
coronoid process – fits in coronoid fossa when elbow flexed
trochlear notch – articulates with trochlea of humerus
radial notch – articulates with head of proximal radius
head – articulates with carpus via a fibrocartilage disc
and distal radius
styloid process
Radius – lateral antebrachium (thumb side)
Parts of Radius:
head – articulates with capitulum of humerus and radial notch of
proximal ulna
radial tuberosity
ulnar notch – articulates with head of distal ulna
scaphoid and lunate notches – articulate with carpals of wrist
styloid process
(Interosseus membrane – dense, fibrous connective tissue joining shafts
of radius and ulna)
Carpals – 8 bones of wrist (2 rows of 4 bones); connected by ligaments; names
reflect their shapes
Proximal Row (lateral-medial/thumb-pinky)
scaphoid (most commonly fractured), lunate, triquetrum, pisiform
Distal Row (lat.-med.)
trapezium, trapezoid, capitate, hamate
carpal tunnel – bordered by pisiform & hamate medially, scaphoid &
trapezium laterally, flexor retinaculum anteriorly, and proximal carpals
posteriorly
Metacarpals – 5 bones of palm; numbered 1-5 starting laterally (thumb side)
Parts of Metacarpal:
base – articulates with distal row of carpals
shaft
head (knuckle) – articulates with proximal phalanges
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Phalanges (sing. phalanx) – 14 bones of fingers; numbered 1-5 starting with
pollex (thumb)
proximal, middle, and distal phalanges (pollex has no middle phalanx)
Parts of Phalanx:
base – proximal phalanges articulate with heads of metacarpals;
others are interphalangeal joints
shaft
head – form interphalangeal joints; distal phalanges don’t articulate
PELVIC GIRDLE – 2 coxal bones (os coxae)
pubic symphysis – joint between 2 coxal bones; joined by fibrocartilage disc
sacroiliac joint – posterior joints where coxae articulate with sacrum
coxa develops from 3 “bones” in fetus which fuse
3 Parts of Coxae:
1) Ilium – largest, superior portion
ala (wing) – iliac crest (superior border)
anterior & posterior superior iliac spines
anterior & posterior inferior iliac spines
greater sciatic notch
iliac fossa (medial surface)
gluteal lines (lateral surface)
body – fuses with ischium and pubis; forms part of acetabulum
auricular surface – articulates with sacrum
2) Ischium – inferior, posterior portion (“sit bones”)
body – forms part of acetabulum
ischial spine
lesser sciatic notch
ischial tuberosity
ramus of ischium – fuses with pubis
3) Pubis – inferior, anterior portion; forms pubic symphysis
superior ramus – forms part of acetabulum
inferior ramus – site of pubic symphysis
body – junction of rami
pubic crest
obturator foramen – large hole between ischium and pubis
acetabulum – deep, rimmed socket which articulates with head of femur; formed
by fusion of all 3 parts of the coxal bone
Bony Pelvis – ring composed of coxal bones joined at pubic symphysis and sacrum;
supports vertebral column and supports and protects pelvic organs
articulates with lower limbs and provides attachment sites for muscles
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Pelvic brim – bony ring formed by sacral promontory, arcuate lines, iliopectineal
lines, and pubic symphysis
True pelvis – surrounds pelvic cavity
pelvic inlet – opening onto true pelvis (pelvic brim)
pelvic outlet – opening out of true pelvis
pelvic axis – route of baby’s head descending through true pelvis
False pelvis – ilium superior to pelvic brim
Female Pelvis vs Male Pelvis (Fig 8-10)
female pelvis adapted to form larger true pelvis for passage of infant at birth
PELVIC LIMB -30 bones; thigh, leg, ankle and foot
Femur – femoral region; longest, heaviest, strongest bone
Parts of Femur:
head – articulates with acetabulum of pelvis
fovea capitis
neck
greater & lesser trochanters
body (shaft)
gluteal tuberosity / linea aspera - posterior
medial & lateral condyles – articulate with tibia
intercondylar fossa(notch)
medial & lateral epicondyles
patellar surface – articulates with patella
Patella (kneecap) – sesamoid bone; increases muscle leverage, maintains tendon
position, protects knee joint
Parts of Patella:
base – broad, superior end
apex – pointed, inferior end
articular facets – articulate with patellar surface of femur
Tibia – medial crus; weight-bearing
Parts of Tibia:
medial & lateral condyles – articulate with condyles of femur;
lateral condyle’s inferior surface articulates with fibula
intercondylar eminence
tibial tuberosity – anterior attachment for patellar ligament
anterior crest (shin)
medial malleolus – articulates with talus of tarsus
fibular notch – articulates with distal fibula
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Fibula – lateral crus; not weight-bearing
Parts of Fibula:
head – articulates with lateral condyle of proximal tibia
lateral malleolus – articulates with talus of tarsus and distal tibia
(interosseus membrane connects shafts of tibia and fibula)
Tarsals – 7 bones of tarsus and calcaneal region
Talus – most proximal; articulates with tibia and fibula
Calcaneus – heel; largest and strongest tarsal
Navicular – between talus and distal tarsals
4 bones form distal row (numbered medial to lateral):
First(medial) cuneiform
Second(intermediate) cuneiform
Third(lateral) cuneiform
Cuboid
Metatarsals – 5 bones of midfoot; numbered 1-5 medial to lateral
Parts of Metatarsal:
base – articulates with tarsals
shaft
head – articulates with phalanges
Phalanges – 14 bones of toes; numbered 1-5 from hallux (big toe)
similar to digits of hands
Arches of Foot – support and distribute weight, provide leverage for walking,
absorb shock; supported by ligaments and tendons
2 arches:
longitudinal arch
transverse arch
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