Transcript The Human Skeleton

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Composed of 126 bones
 Limbs (appendages)
 Pectoral girdle
 Pelvic girdle
Figure 5.6a
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Composed of two
bones
 Clavicle — collarbone
 Scapula — shoulder
blade
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These bones allow the
upper limb to have
exceptionally free
movement
Figure 5.21c–d
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Slender, rodlike bones with
elongated S shapes
Located at base of the neck and
run horizontally between the
sternum and the shoulders
Sternal ends – articulate with the
manubrium
Acromial ends – articulate with
the scapulae
Brace the scapulae, holding the
shoulders in place
Structurally weak
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Broad, triangular bones
located on either side of the
upper back
Spine – divides posterior
surface
2 processes at the head:
 Acromion process – forms tip of
the shoulder and articulates with
the clavicle
 Coracoid process – curves
anteriorly and inferiorly to the
clavicle
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Glenoid cavity – between the
acromion and coracoid
processes; articulates with the
head of the humerus
Suprascapular notch –
passage way for nerves
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Bones form the framework
of the arm, forearm, and
hand
Bones function as levers for
muscle contraction
Includes:
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Humerus (2)
Radius (2)
Ulna (2)
Carpals (16)
Metacarpals (10)
Phalanges (28)
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Long bone that extends
from scapula to the elbow
Head fits into glenoid cavity
of scapula
Greater tubercle – on
lateral side
Lesser tubercle – on
anterior side
Surgical neck – tapering
region below head and
tubercles (common fracture
site)
Deltoid tuberosity – rough
area near the middle of the
shaft on the lateral side
 attachment site for the deltoid
muscle
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Coronoid fossa – process
where the elbow bends:
receives the ulna
Capitulum – articulates
with the radius
Olecranon fossa – on
posterior surface, receives
the olecranon process of
the ulna when the elbow
straightens
Trochlea – articulates with
the ulna
Epicondyles – attachments
for elbow muscles and
ligaments
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On thumb side of forearm
Shorter than the ulna
Extends from the elbow to
the wrist and crosses over
the ulna when hand is
turned over at the wrist
Radial tuberosity – process
just below the head;
attachment for the biceps
Styloid process –
attachment for wrist
ligaments at the distal end
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Longer than the radius
Trochlear notch – at proximal
end, wrench-like opening that
articulates with the trochlea
of the humerus
Olecranon process – above
the trochlear notch;
attachment for triceps that
straightens the upper limb at
the elbow; fits into olecranon
fossa
Coronoid process – below
trochlear notch, fits into
coronoid fossa when elbow
bends
Styloid process – at distal
end provides attachment for
wrist ligaments
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Wrist consists of carpals
bound in 2 rows of 4 bones
each
Articulate with radius and
ulna proximally and
metacarpals distally
Carpal bones are:
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Pisiform
Triquetrum
Lunate
Scaphoid
Hamate
Capitate
Trapezoid
Trapezium
She Left Town. Please Take
The Cat Home
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Form the palm of the hand
5 per hand
Long bones with rounded
distal ends (knuckles)
Articulate with carpals and
phalanges
Lateral metacarpal is the
most freely moveable
Numbered 1-5, starting at
the thumb
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Finger bones
3 per finger (proximal,
middle, and distal)
2 in thumb – no middle
phalanx
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The total weight
of the upper
body rests on
the pelvis
It protects
several organs
 Reproductive
organs
 Urinary bladder
 Part of the large
intestine
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Each coxa develops from 3 parts:
 Ilium
 Ishium
 Pubis
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Acetabulum – cup-shaped cavity where the 3 parts of coxa
fuse, making the socket for the femur
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Largest and most superior
portion of the coxa
Flares outward and forms
the prominence of the hip
Iliac crest – margin of the
ilium
Sacroiliac joint – where
ilium and sacrum join
Anterior superior iliac
spine – found lateral to the
groin, provides
attachments for ligaments
and muscles
Posterior superior iliac
spine – on posterior border
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Forms lowest portion of the
coxa
L-shaped
Ischial tuberosity – rough
surface that points down and
back; supports body weight
when sitting
Ischial spine – sharp
projection above ischial
tuberosity, near the junction
between the ilium and the
ischium
 Creates the narrowest part of the
pelvis
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Anterior portion of coxa
Pubic symphysis – fibrocartilage joint between the 2 pubic bones
Pubic arch – angle between pubic bones
Obturator foramen – largest opening in the body
 Formed between ischium and pubis
 Covered and nearly closed by obturator membrane
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Male Pelvis:
 Heavier bone
 More evidence of muscle
attachments
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Female Pelvis
 Iliac bones are more
flared
 Broader hips
 Greater angle of pubic
arch
 Greater distance
between ischial spines
and tuberosities
 Shorter, flatter sacral
curvature
 More delicate bones
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Femur (2)
Patella (2)
Tibia (2)
Fibula (2)
Tarsals (7/foot)
Metatarsals (5/foot)
Phalanges (14/foot)
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Thigh bone
Longest bone in body
Extends from hip to knee
Head of femur – large and
rounded; projects medially
into acetabulum of coxal
bone
Greater trochanter and
lesser trochanter –
attachments for muscles of
buttocks and lower limbs
Lateral and medial
condyles – articulate with
tibia
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Articulates with the femur
on distal anterior surface
Kneecap
Flat sesamoid bone located
in a tendon that passes
anteriorly over the knee
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Shin bone
Larger of 2 leg bones;
located on the medial side
Medial and lateral
condyles – on proximal
end, articulate with
condyles of femur
Tibial tuberosity – below
condyles on anterior
surface; attachment of
patellar ligament
Anterior crest – extends
downward from tuberosity;
Medial malleolus – inner
ankle
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Long, slender bone
located on the lateral
side of the tibia
Articulates with the
tibia just below the
lateral condyle
Lateral malleolus –
distal end that forms
the outer ankle
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Tarsus – consists of 7 tarsal
bones
Talus – tarsal bone that can
move freely where it joins
the tibia and fibula
 Forms the ankle
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Other tarsals are bound
firmly together to support
the talus
Calcaneus – largest tarsal
bone; heel bone
 Located below the talus and
projects backward
 Helps support weight of the
body
Cute Tilley Never Could Cooperate Cuddle or Cuss
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Numbered 1-5 beginning on
the medial side
Ball of the foot formed by
the distal ends
If tissues that bind the
metatarsals weaken fallen
arches (flat feet) occurs
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Shorter, but otherwise
similar to fingers
3 bones per toe, except
2 in the great toe