Download Classification of Bones

Chapter 5
The Skeletal System
Lecture Presentation by
Patty Bostwick-Taylor
Florence-Darlington Technical College
© 2015 Pearson Education, Inc.
The Skeletal System
 Two subdivisions of the skeleton
1. Axial skeleton
2. Appendicular skeleton
 Parts of the skeletal system
 Bones (skeleton)
 Joints
 Cartilages
 Ligaments
© 2015 Pearson Education, Inc.
Functions of Bones
 Support the body
 Protect soft organs
 Skull and vertebrae protect brain and spinal cord
 Rib cage protects thoracic cavity organs
 Attached skeletal muscles allow movement
 Store minerals and fats
 Calcium and phosphorus
 Fat in the internal marrow cavity
 Blood cell formation (hematopoiesis)
© 2015 Pearson Education, Inc.
Bones of the Human Body
 The adult skeleton has 206 bones
 Two basic types of bone tissue
1. Compact bone
 Dense, smooth, and homogeneous
2. Spongy bone
 Small needle-like pieces of bone
 Many open spaces
© 2015 Pearson Education, Inc.
Figure 5.1 Flat bones consist of a layer of spongy bone sandwiched between two thin layers of compact bone.
Spongy
bone
Compact
bone
© 2015 Pearson Education, Inc.
Classification of Bones
 Bones are classified on the basis of shape, as:
 Long
 Short
 Flat
 Irregular
© 2015 Pearson Education, Inc.
Figure 5.2 Classification of bones on the basis of shape.
(a) Long bone
(humerus)
(b) Irregular bone
(vertebra),
right lateral view
© 2015 Pearson Education, Inc.
(c) Flat bone
(sternum)
(d) Short bone
(talus)
Classification of Bones
 Long bones
 Typically longer than they are wide
 Shaft with heads situated at both ends
 Contain mostly compact bone
 All of the bones of the limbs (except wrist, ankle, and
kneecap bones) are long bones
 Examples:
 Femur
 Humerus
© 2015 Pearson Education, Inc.
Classification of Bones
 Short bones
 Generally cube-shaped
 Contain mostly spongy bone
 Include bones of the wrist and ankle
 Sesamoid bones are a type of short bone that form
within tendons (patella)
 Examples:
 Carpals
 Tarsals
© 2015 Pearson Education, Inc.
Classification of Bones
 Flat bones
 Thin, flattened, and usually curved
 Two thin layers of compact bone surround a layer of
spongy bone
 Examples:
 Skull
 Ribs
 Sternum
© 2015 Pearson Education, Inc.
Classification of Bones
 Irregular bones
 Irregular shape
 Do not fit into other bone classification categories
 Examples:
 Vertebrae
 Hip bones
© 2015 Pearson Education, Inc.
Anatomy of a Long Bone
 Diaphysis
 Shaft
 Makes up most of bone’s length
 Composed of compact bone
 Periosteum
 Outside covering of the diaphysis
 Fibrous connective tissue membrane
 Perforating (Sharpey’s) fibers secure periosteum to
underlying bone
© 2015 Pearson Education, Inc.
Figure 5.3a The structure of a long bone (humerus of arm).
Articular
cartilage
Proximal
epiphysis
Spongy bone
Epiphyseal
line
Periosteum
Compact bone
Medullary
cavity (lined
by endosteum)
Diaphysis
(a)
© 2015 Pearson Education, Inc.
Distal
epiphysis
Figure 5.3c The structure of a long bone (humerus of arm).
Endosteum
Yellow bone
marrow
Compact bone
Periosteum
Perforating
(Sharpey’s) fibers
Nutrient
arteries
(c)
© 2015 Pearson Education, Inc.
Anatomy of a Long Bone
 Epiphysis
 Ends of the bone
 Composed mostly of spongy bone enclosed by thin
layer of compact bone
 Articular cartilage
 Covers the external surface of the epiphyses
 Made of hyaline cartilage
 Decreases friction at joint surfaces
© 2015 Pearson Education, Inc.
Figure 5.3b The structure of a long bone (humerus of arm).
Articular
cartilage
Spongy
bone
(b)
© 2015 Pearson Education, Inc.
Compact
bone
Anatomy of a Long Bone
 Epiphyseal plate
 Flat plate of hyaline cartilage seen in young, growing
bone
 Causes lengthwise growth of a long bone
 Epiphyseal line
 Remnant of the epiphyseal plate
 Seen in adult bones
© 2015 Pearson Education, Inc.
Figure 5.3a The structure of a long bone (humerus of arm).
Articular
cartilage
Proximal
epiphysis
Spongy bone
Epiphyseal
line
Periosteum
Compact bone
Medullary
cavity (lined
by endosteum)
Diaphysis
(a)
© 2015 Pearson Education, Inc.
Distal
epiphysis
Anatomy of a Long Bone
 Marrow (medullary) cavity
 Cavity inside the shaft
 Contains yellow marrow (mostly fat) in adults
 Contains red marrow for blood cell formation in
infants
 In adults, red marrow is situated in cavities of
spongy bone and epiphyses of some long bones
© 2015 Pearson Education, Inc.
Bone Markings
 Surface features of bones
 Sites of attachments for muscles, tendons, and
ligaments
 Passages for nerves and blood vessels
 Categories of bone markings
 Projections or processes—grow out from the bone
surface
 Terms often begin with “T”
 Depressions or cavities—indentations
 Terms often begin with “F”
© 2015 Pearson Education, Inc.
Table 5.1 Bone Markings (1 of 3).
© 2015 Pearson Education, Inc.
Table 5.1 Bone Markings (2 of 3).
© 2015 Pearson Education, Inc.
Table 5.1 Bone Markings (3 of 3).
© 2015 Pearson Education, Inc.
Microscopic Anatomy of Compact Bone
 Osteocytes are situated within cavities known as
lacunae
 Lacunae are arranged in concentric rings called
lamellae
 Lamellae are rings situated around the central
(Haversian) canal
© 2015 Pearson Education, Inc.
Figure 5.4a Microscopic structure of compact bone.
Spongy bone
Osteon
(Haversian
system)
Lamellae
Perforating
(Volkmann’s) canal
Blood vessel continues
into medullary cavity
containing marrow
Blood vessel
Compact bone
Central (Haversian) canal
Perforating (Sharpey’s) fibers
Periosteum
Periosteal blood vessel
(a)
© 2015 Pearson Education, Inc.
Microscopic Anatomy of Bone
 Central (Haversian) canal
 Opening in the center of an osteon
 Runs lengthwise through bone
 Carries blood vessels and nerves
 Osteon (Haversian system)
 A unit of bone containing central canal and matrix
rings
© 2015 Pearson Education, Inc.
Figure 5.4b Microscopic structure of compact bone.
Lamella
Osteocyte
(b)
© 2015 Pearson Education, Inc.
Canaliculus
Lacuna
Central
(Haversian) canal
Figure 5.4c Microscopic structure of compact bone.
Osteon
Interstitial
lamellae
Lacuna
Central
(Haversian) canal
(c)
© 2015 Pearson Education, Inc.
Microscopic Anatomy of Bone
 Canaliculi
 Tiny canals
 Radiate from the central canal to lacunae
 Form a transport system connecting all bone cells to
a nutrient supply
 Perforating (Volkmann’s) canal
 Canal perpendicular to the central canal
 Carries blood vessels and nerves
© 2015 Pearson Education, Inc.
Bone Components
 Organic parts of the matrix make bone flexible
 Calcium salts deposited in the matrix make bone
hard
© 2015 Pearson Education, Inc.
Bone Formation and Growth
 Ossification
 Process of bone formation
 Occurs on hyaline cartilage models or fibrous
membranes
 Long bone growth involves two major phases
© 2015 Pearson Education, Inc.
Figure 5.5 Stages of long-bone formation in an embryo, fetus, and young child.
Articular
cartilage
Hyaline
cartilage
Spongy
bone
New center of
bone growth
Epiphyseal
plate
cartilage
Medullary
cavity
Bone starting
to replace
cartilage
© 2015 Pearson Education, Inc.
Growth
in bone
width
Invading
Growth blood
in bone vessels
length
New bone
forming
Bone collar
Hyaline
cartilage
model
In an embryo
New bone
forming
Epiphyseal
plate cartilage
In a fetus
In a child
Bone Formation and Growth
Two major phases of ossification in long bones
1. Osteoblasts
 Bone-forming cells
 Cover hyaline cartilage model
2. Enclosed cartilage is digested away, opening up a
medullary cavity
© 2015 Pearson Education, Inc.
Bone Formation and Growth
 By birth, most cartilage is converted to bone except
for two regions in a long bone:
1. Articular cartilages
2. Epiphyseal plates
 New cartilage is formed continuously on external
face of these two cartilages
 Old cartilage is broken down and replaced by bony
matrix
© 2015 Pearson Education, Inc.
Figure 5.6 Growth and remodeling of long bones.
Bone growth
Bone grows in
length because:
1 Cartilage
grows here.
2 Cartilage
is replaced
by bone here.
3 Cartilage
grows here.
4 Cartilage
is replaced by
bone here.
© 2015 Pearson Education, Inc.
Bone remodeling
Growing shaft is
remodeled as:
Articular cartilage
Epiphyseal plate
1 Bone is
resorbed here.
2 Bone is added
by appositional
growth here.
3 Bone is
resorbed here.
Bone Formation and Growth
 Bones grow in length and width
 Appositional growth
 Growth in diameter
 Controlled by hormones such as growth hormone
 Epiphyseal plates are converted to bone during
adolescence
 Growth in length ends
© 2015 Pearson Education, Inc.
Bone Remodeling
 Bones are lengthened until growth stops
 Bones are remodeled throughout life in response to
two factors:
1. Blood calcium levels
2. Pull of gravity and muscles on the skeleton
© 2015 Pearson Education, Inc.
Bone Remodeling
 Parathyroid hormone (PTH)
 Released when blood calcium levels are low
 Activates osteoclasts (bone-destroying cells)
 Osteoclasts break down bone and release calcium
ions into the blood
 Hypercalcemia (high blood calcium levels) prompts
calcium storage to bones
© 2015 Pearson Education, Inc.
Bone Fractures
 Fracture: break in a bone
 Types of bone fractures
 Closed (simple) fracture: break that does not
penetrate the skin
 Open (compound) fracture: broken bone penetrates
through the skin
© 2015 Pearson Education, Inc.
Bone Fractures
 Bone fractures are treated by reduction and
immobilization
 Closed reduction: bones are manually coaxed into
position by physician’s hands
 Open reduction: bones are secured with pins or
wires during surgery
© 2015 Pearson Education, Inc.
Repair of Bone Fractures
 Hematoma (blood-filled swelling) is formed
 Fibrocartilage callus forms
 Cartilage matrix, bony matrix, collagen fibers splint
the broken bone
 Bony callus replaces the fibrocartilage callus
 Osteoblasts and osteoclasts migrate in
 Bone remodeling occurs in response to mechanical
stresses
© 2015 Pearson Education, Inc.
Figure 5.7 Stages in the healing of a bone fracture.
Hematoma
External
callus
Internal
callus
(fibrous
tissue and
cartilage)
1 Hematoma
forms.
© 2015 Pearson Education, Inc.
2 Fibrocartilage
callus forms.
New
blood
vessels
Bony
callus of
spongy
bone
Healed
fracture
Spongy
bone
trabecula
3 Bony callus
forms.
4 Bone
remodeling
occurs.
Common Types of Fractures
 Comminuted: bone breaks into many fragments
 Compression: bone is crushed
 Depressed: broken bone portion is pressed inward
 Impacted: broken bone ends are forced into each
other
 Spiral: ragged break occurs when excessive
twisting forces are applied to a bone
 Greenstick: bone breaks incompletely
© 2015 Pearson Education, Inc.
Table 5.2 Common Types of Fractures.
© 2015 Pearson Education, Inc.
The Axial Skeleton
 Forms the longitudinal axis of the body
 Divided into three parts
1. Skull
2. Vertebral column
3. Bony thorax
© 2015 Pearson Education, Inc.
Figure 5.8a The human skeleton.
Skull
Cranium
Facial bones
Clavicle
Thoracic
cage
(ribs and
sternum)
Vertebral
column
Sacrum
Scapula
Sternum
Rib
Humerus
Vertebra
Radius
Ulna
Carpals
Phalanges
Metacarpals
Femur
Patella
Tibia
Fibula
(a) Anterior view
© 2015 Pearson Education, Inc.
Tarsals
Metatarsals
Phalanges
Figure 5.8b The human skeleton.
Cranium
Bones of
pectoral
girdle
Clavicle
Scapula
Rib
Humerus
Vertebra
Radius
Ulna
Carpals
Upper
limb
Bones of
pelvic
girdle
Phalanges
Metacarpals
Femur
Lower
limb
Tibia
Fibula
(b) Posterior view
© 2015 Pearson Education, Inc.
The Skull
 Two sets of bones
1. Cranium bones enclose the brain
2. Facial bones
 Hold eyes in anterior position
 Allow facial muscles to express feelings
 Bones are joined by sutures
 Only the mandible is attached by a freely movable
joint
© 2015 Pearson Education, Inc.
The Skull
 8 cranial bones protect the brain
1.
2.
3.
4.
5–6.
7–8.
© 2015 Pearson Education, Inc.
Frontal bone
Occipital bone
Ethmoid bone
Sphenoid bone
Parietal bones (pair)
Temporal bones (pair)
The Skull
 There are 14 facial bones. All are paired except for
the single mandible and vomer.
1–2.
3–4.
5–6.
7–8.
9–10.
11–12.
13.
14.
Maxillae
Zygomatics
Palatines
Nasals
Lacrimals
Inferior nasal conchae
Mandible
Vomer
© 2015 Pearson Education, Inc.
Figure 5.9 Human skull, lateral view.
Coronal suture
Frontal bone
Parietal bone
Sphenoid bone
Temporal bone
Ethmoid bone
Lambdoid suture
Lacrimal bone
Squamous suture
Occipital bone
Nasal bone
Zygomatic process
Zygomatic bone
Maxilla
External acoustic
meatus
Mastoid process
Alveolar processes
Styloid process
Mandibular ramus
© 2015 Pearson Education, Inc.
Mandible (body)
Mental foramen
Figure 5.11 Human skull, inferior view (mandible removed).
Maxilla
(palatine process)
Hard
palate Palatine bone
Zygomatic bone
Temporal bone
(zygomatic process)
Maxilla
Sphenoid bone
(greater wing)
Foramen ovale
Vomer
Mandibular fossa
Carotid canal
Styloid process
Mastoid process
Temporal bone
Jugular foramen
Occipital condyle
Parietal bone
Foramen magnum
Occipital bone
© 2015 Pearson Education, Inc.
Figure 5.12 Human skull, anterior view.
Coronal suture
Frontal bone
Parietal bone
Nasal bone
Sphenoid bone
Ethmoid bone
Lacrimal bone
Zygomatic bone
Maxilla
Superior orbital
fissure
Optic canal
Temporal bone
Middle nasal concha
of ethmoid bone
Inferior nasal concha
Vomer
Mandible
Alveolar processes
© 2015 Pearson Education, Inc.
The Hyoid Bone
 Closely related to mandible and temporal bones
 The only bone that does not articulate with another
bone
 Serves as a movable base for the tongue
 Aids in swallowing and speech
© 2015 Pearson Education, Inc.
Figure 5.14 Anatomical location and structure of the hyoid bone.
Greater horn
Lesser horn
Body
© 2015 Pearson Education, Inc.
The Fetal Skull
 The fetal skull is large compared to the infant’s total
body length
 Fetal skull is 1/4 body length compared to adult skull,
which is 1/8 body length
 Fontanels are fibrous membranes connecting the
cranial bones
 Allow skull compression during birth
 Allow the brain to grow during later pregnancy and
infancy
 Convert to bone within 24 months after birth
© 2015 Pearson Education, Inc.
Figure 5.15a The fetal skull.
Frontal bone
Anterior
fontanel
Parietal
bone
Posterior fontanel
(a)
© 2015 Pearson Education, Inc.
Occipital
bone
Figure 5.15b The fetal skull.
Parietal bone
Posterior
fontanel
Occipital
bone
Mastoid
fontanel
© 2015 Pearson Education, Inc.
Anterior fontanel
Sphenoidal
fontanel
Frontal
bone
Temporal bone
Vertebral Column (Spine)
 Vertebral column provides axial support
 Extends from skull to the pelvis
 26 single vertebral bones are separated by
intervertebral discs
 7 cervical vertebrae are in the neck
 12 thoracic vertebrae are in the chest region
 5 lumbar vertebrae are associated with the lower
back
© 2015 Pearson Education, Inc.
Vertebral Column (Spine)
 9 vertebrae fuse to form two composite bones
 Sacrum formed by the fusion of 5 vertebrae
 Coccyx (tailbone) formed by the fusion of 3 to 5
vertebrae
© 2015 Pearson Education, Inc.
Figure 5.16 The vertebral column.
Anterior
1st cervical vertebra
(atlas)
2nd cervical vertebra
(axis)
Posterior
Cervical curvature (concave)
7 vertebrae, C1 – C7
1st thoracic vertebra
Transverse process
Spinous process
Thoracic curvature (convex)
12 vertebrae, T1 – T12
Intervertebral disc
Intervertebral foramen
1st lumbar vertebra
Lumbar curvature (concave)
5 vertebrae, L1 – L5
Sacral curvature (convex)
5 fused vertebrae
Coccyx
4 fused vertebrae
© 2015 Pearson Education, Inc.
Vertebral Column (Spine)
 Primary curvatures
 Spinal curvatures of the thoracic and sacral regions
 Present from birth
 Form a C-shaped curvature as in newborns
 Secondary curvatures
 Spinal curvatures of the cervical and lumbar regions
 Develop after birth
 Form an S-shaped curvature as in adults
© 2015 Pearson Education, Inc.
Figure 5.17 The C-shaped spine typical of a newborn.
© 2015 Pearson Education, Inc.
Figure 5.18 Abnormal spinal curvatures.
(a) Scoliosis
© 2015 Pearson Education, Inc.
(b) Kyphosis
(c) Lordosis
Vertebral Column (Spine)
 Parts of a typical vertebra
 Body (centrum)
 Vertebral arch
 Pedicle
 Lamina
 Vertebral foramen
 Transverse processes
 Spinous process
 Superior and inferior articular processes
© 2015 Pearson Education, Inc.
Figure 5.19 A typical vertebra, superior view.
Posterior
Vertebral
arch
Lamina
Transverse
process
Spinous
process
Superior
articular
process
and
facet
Pedicle
Vertebral
foramen
Body
Anterior
© 2015 Pearson Education, Inc.
Figure 5.20a Regional characteristics of vertebrae.
(a) ATLAS AND AXIS
Transverse
process
Posterior
arch
Anterior arch
Superior view of atlas (C1)
Transverse
process
Spinous process
Facet on
superior
articular
process
Dens
Body
Superior view of axis (C2)
© 2015 Pearson Education, Inc.
Figure 5.20b Regional characteristics of vertebrae.
(b) TYPICAL CERVICAL VERTEBRAE
Spinous process
Vertebral
foramen
Facet on
superior
articular
process
Superior view
Superior articular
process
Spinous
process
Transverse
process
Body
Transverse
process
Facet on inferior
articular process
Right lateral view
© 2015 Pearson Education, Inc.
Figure 5.20c Regional characteristics of vertebrae.
(c) THORACIC VERTEBRAE
Spinous process
Vertebral
Transverse
foramen
process
Facet on
superior
Facet
articular
for rib
process
Body
Facet on Superior view
superior
Body
articular
process
Facet on
Costal facet
transverse
Spinous
for rib
process
process
Right lateral view
© 2015 Pearson Education, Inc.
Figure 5.20d Regional characteristics of vertebrae.
(d) LUMBAR VERTEBRAE
Spinous process
Vertebral
Transverse
foramen
process
Facet on
superior
articular
process
Body
Superior view
Superior
articular
process
Spinous
process
© 2015 Pearson Education, Inc.
Body
Facet on inferior
articular process
Right lateral view
Figure 5.21 Sacrum and coccyx, posterior view.
Sacral
canal
Ala
Superior Auricular
articular surface
process
Body
Median
sacral
crest
Sacrum
Posterior
sacral
foramina
Coccyx
© 2015 Pearson Education, Inc.
Sacral
hiatus
The Bony Thorax
 Forms a cage to protect major organs
 Consists of three parts
1. Sternum
2. Ribs
 True ribs (pairs 1–7)
 False ribs (pairs 8–12)
 Floating ribs (pairs 11–12)
3. Thoracic vertebrae
© 2015 Pearson Education, Inc.
Figure 5.22a The bony thorax (thoracic cage).
T1 vertebra
Jugular notch
Clavicular notch
Manubrium
Sternal angle
Body
Xiphisternal
joint
Xiphoid
process
True
ribs
(1–7)
False
ribs
(8–12)
L1
vertebra
(a)
© 2015 Pearson Education, Inc.
Floating
ribs (11, 12)
Intercostal
spaces
Costal cartilage
Sternum
Figure 5.22b The bony thorax (thoracic cage).
T2
T3
T4
Jugular
notch
Sternal
angle
Heart
T9
(b)
© 2015 Pearson Education, Inc.
Xiphisternal
joint
The Appendicular Skeleton
 Composed of 126 bones
 Limbs (appendages)
 Pectoral girdle
 Pelvic girdle
© 2015 Pearson Education, Inc.
Figure 5.8a The human skeleton.
Skull
Cranium
Facial bones
Clavicle
Thoracic
cage
(ribs and
sternum)
Vertebral
column
Sacrum
Scapula
Sternum
Rib
Humerus
Vertebra
Radius
Ulna
Carpals
Phalanges
Metacarpals
Femur
Patella
Tibia
Fibula
(a) Anterior view
© 2015 Pearson Education, Inc.
Tarsals
Metatarsals
Phalanges
Figure 5.8b The human skeleton.
Cranium
Bones of
pectoral
girdle
Clavicle
Scapula
Rib
Humerus
Vertebra
Radius
Ulna
Carpals
Upper
limb
Bones of
pelvic
girdle
Phalanges
Metacarpals
Femur
Lower
limb
Tibia
Fibula
(b) Posterior view
© 2015 Pearson Education, Inc.
The Pectoral (Shoulder) Girdle
 Composed of two bones that attach the upper limb
to the axial skeletal
1. Scapula
2. Clavicle
 Pectoral girdle (2)
 Light, poorly reinforced girdle
 Allows the upper limb a great deal of freedom
© 2015 Pearson Education, Inc.
Figure 5.23a Bones of the shoulder girdle.
Acromioclavicular joint
Clavicle
Scapula
(a) Articulated right shoulder (pectoral)
girdle showing the relationship to
bones of the thorax and sternum
© 2015 Pearson Education, Inc.
Figure 5.23b Bones of the shoulder girdle.
Sternal
(medial)
end
Posterior
Acromial
(lateral) end
Superior view
Acromial end
Anterior
Anterior
Sternal end
Posterior
Inferior view
(b) Right clavicle, superior and
inferior views
© 2015 Pearson Education, Inc.
Figure 5.23c Bones of the shoulder girdle.
Coracoid process
Suprascapular notch
Superior
angle
Spine
Acromion
Glenoid cavity
at lateral angle
Medial
border
Lateral border
(c) Right scapula, posterior aspect
© 2015 Pearson Education, Inc.
Figure 5.23d Bones of the shoulder girdle.
Acromion
Suprascapular notch
Superior border
Superior
angle
Coracoid
process
Glenoid
cavity
Lateral
(axillary)
border
Medial
(vertebral)
border
Inferior angle
(d) Right scapula, anterior aspect
© 2015 Pearson Education, Inc.
Bones of the Upper Limbs
 Humerus
 Forms the arm
 Single bone
 Proximal end articulation
 Head articulates with the glenoid cavity of the scapula
 Distal end articulation
 Trochlea and capitulum articulate with the bones of
the forearm
© 2015 Pearson Education, Inc.
Figure 5.24a Bones of the right arm and forearm.
Greater
tubercle
Lesser
tubercle
Head of
humerus
Anatomical
neck
Intertubercular
sulcus
Deltoid
tuberosity
(a)
© 2015 Pearson Education, Inc.
Radial
fossa
Coronoid
fossa
Medial
epicondyle
Capitulum
Trochlea
Figure 5.24b Bones of the right arm and forearm.
Head of
humerus
Anatomical
neck
Surgical
neck
Radial
groove
Deltoid
tuberosity
Medial
epicondyle
(b) Trochlea
© 2015 Pearson Education, Inc.
Olecranon
fossa
Lateral
epicondyle
Bones of the Upper Limbs
 The forearm has two bones
1. Ulna—medial bone in anatomical position
 Proximal end articulation
 Coronoid process and olecranon articulate with the
humerus
2. Radius—lateral bone in anatomical position
 Proximal end articulation
 Head articulates with the capitulum of the humerus
© 2015 Pearson Education, Inc.
Figure 5.24c Bones of the right arm and forearm.
Trochlear
notch
Olecranon
Head
Neck
Radial
tuberosity
Coronoid
process
Proximal
radioulnar
joint
Radius
Ulna
Interosseous
membrane
(c)
© 2015 Pearson Education, Inc.
Radial
styloid
process
Ulnar
styloid
process
Distal
radioulnar joint
Bones of the Upper Limbs
 Hand
 Carpals—wrist
 8 bones arranged in two rows of 4 bones in each
hand
 Metacarpals—palm
 5 per hand
 Phalanges—fingers and thumb
 14 phalanges in each hand
 In each finger, there are 3 bones
 In the thumb, there are only 2 bones
© 2015 Pearson Education, Inc.
Figure 5.25 Bones of the right hand, anterior view.
Distal
Phalanges
(fingers)
Middle
Proximal
Metacarpals
(palm)
Carpals
(wrist)
4
3
2
5
1
Hamate
Trapezium
Pisiform
Triquetrum
Trapezoid
Scaphoid
Capitate
Lunate
Ulna
Radius
© 2015 Pearson Education, Inc.
Bones of the Pelvic Girdle
 Formed by 2 coxal (ossa coxae) bones
 Composed of three pairs of fused bones
1. Ilium
2. Ischium
3. Pubis
 Pelvic girdle  2 coxal bones, sacrum
 Bony pelvis  2 coxal bones, sacrum, coccyx
© 2015 Pearson Education, Inc.
Bones of the Pelvic Girdle
 The total weight of the upper body rests on the
pelvis
 Pelvis protects several organs
 Reproductive organs
 Urinary bladder
 Part of the large intestine
© 2015 Pearson Education, Inc.
Figure 5.26a The bony pelvis.
Iliac crest
Sacroiliac
joint
Ilium
Coxal bone
(or hip bone)
Sacrum
Pubis
Pelvic brim
Coccyx
Ischial spine
Acetabulum
Ischium
(a)
© 2015 Pearson Education, Inc.
Pubic symphysis
Pubic arch
Figure 5.26b The bony pelvis.
Ilium
Ala
Posterior
superior
iliac spine
Posterior
inferior
iliac spine
Greater sciatic
notch
Ischial body
Iliac crest
Anterior superior
iliac spine
Anterior inferior
iliac spine
Acetabulum
Body of pubis
Ischial spine
Pubis
Ischial
tuberosity
Ischium
(b) Ischial ramus
© 2015 Pearson Education, Inc.
Inferior pubic
ramus
Obturator
foramen
Gender Differences of the Pelvis
 The female’s pelvis:
 Inlet is larger and more circular
 Pelvis as a whole is shallower, and the bones are
lighter and thinner
 Ilia flare more laterally
 Sacrum is shorter and less curved
 Ischial spines are shorter and farther apart; thus, the
outlet is larger
 Pubic arch is more rounded because the angle of the
pubic arch is greater
© 2015 Pearson Education, Inc.
Figure 5.26c The bony pelvis.
False pelvis
Inlet of
true
pelvis
Pelvic brim
Pubic arch
)
(less than 90°
False pelvis
Inlet of
true
pelvis
Pelvic brim
(c)
© 2015 Pearson Education, Inc.
Pubic arch
)
(more than 90°
Bones of the Lower Limbs
 Femur—thigh bone
 The heaviest, strongest bone in the body
 Proximal end articulation
 Head articulates with the acetabulum of the coxal
(hip) bone
 Distal end articulation
 Lateral and medial condyles articulate with the tibia in
the lower leg
© 2015 Pearson Education, Inc.
Figure 5.27a Bones of the right thigh and leg.
Neck
Head
Intertrochanteric
line
Lateral
condyle
Patellar
surface
© 2015 Pearson Education, Inc.
(a)
Lesser
trochanter
Figure 5.27b Bones of the right thigh and leg.
Greater
trochanter
Head
Lesser
trochanter
Intertrochanteric
crest
Gluteal
tuberosity
Intercondylar
fossa
Medial
condyle
(b)
© 2015 Pearson Education, Inc.
Lateral
condyle
Bones of the Lower Limbs
 The lower leg has two bones
1. Tibia—shinbone; larger and medially oriented
 Proximal end articulation
 Medial and lateral condyles articulate with the femur to
form the knee joint
2. Fibula—thin and sticklike; lateral to the tibia
 Has no role in forming the knee joint
© 2015 Pearson Education, Inc.
Figure 5.27c Bones of the right thigh and leg.
Intercondylar
eminence
Medial
condyle
Lateral
condyle
Head
Tibial
tuberosity
Proximal
tibiofibular
joint
Interosseous
membrane
Anterior
border
Fibula
Tibia
Distal
tibiofibular
joint
Lateral
malleolus
© 2015 Pearson Education, Inc.
(c)
Medial
malleolus
Bones of the Lower Limbs
 The foot
 Tarsals—7 bones
 Two largest tarsals
 Calcaneus (heel bone)
 Talus
 Metatarsals—5 bones form the sole of
the foot
 Phalanges—14 bones form the toes
© 2015 Pearson Education, Inc.
Figure 5.28 Bones of the right foot, superior view.
Phalanges:
Distal
Middle
Proximal
Tarsals:
Medial
cuneiform
Intermediate
cuneiform
Navicular
Metatarsals
Tarsals:
Lateral
cuneiform
Cuboid
Talus
Calcaneus
© 2015 Pearson Education, Inc.
Joints
 Joints are articulations
 Two or more bones meet
 Functions of joints
 Hold bones together
 Allow for mobility
 Two ways joints are classified
 Functionally
 Structurally
© 2015 Pearson Education, Inc.
Functional Classification of Joints
 Synarthroses
 Immovable joints
 Amphiarthroses
 Slightly movable joints
 Diarthroses
 Freely movable joints
© 2015 Pearson Education, Inc.
Structural Classification of Joints
 Fibrous joints
 Generally immovable
 Cartilaginous joints
 Immovable or slightly movable
 Synovial joints
 Freely movable
© 2015 Pearson Education, Inc.
Fibrous Joints
 Bones united by fibrous tissue
 Types
 Sutures
 Immobile
 Syndesmoses
 Allow more movement than sutures but still immobile
 Example: Distal end of tibia and fibula
 Gomphosis
 Immobile
© 2015 Pearson Education, Inc.
Cartilaginous Joints
 Bones connected by fibrocartilage
 Types
 Synchrondrosis
 Immobile
 Symphysis
 Slightly movable
 Example: Pubic symphysis, intervertebral joints
© 2015 Pearson Education, Inc.
Synovial Joints
 Articulating bones are separated by a joint cavity
 Synovial fluid is found in the joint cavity
 Four distinguishing features of synovial joints
1.
2.
3.
4.
Articular cartilage
Articular capsule
Joint cavity
Reinforcing ligaments
© 2015 Pearson Education, Inc.
Synovial Joints
 Bursae—flattened fibrous sacs
 Lined with synovial membranes
 Filled with synovial fluid
 Not actually part of the joint
 Tendon sheath
 Elongated bursa that wraps around a tendon
© 2015 Pearson Education, Inc.
Synovial Joints
 Types of synovial joints based on shape:
 Plane joint
 Hinge joint
 Pivot joint
 Condylar joint
 Saddle joint
 Ball-and-socket joint
© 2015 Pearson Education, Inc.
Figure 5.31 General structure of a synovial joint.
Acromion of
scapula
Ligament
Joint cavity
containing
synovial fluid
Bursa
Ligament
Articular
(hyaline)
cartilage
Tendon
sheath
Synovial membrane
Fibrous layer of the
articular capsule
Tendon of
biceps muscle
Humerus
© 2015 Pearson Education, Inc.
Figure 5.32a Types of synovial joints.
Nonaxial
Uniaxial
Biaxial
Multiaxial
(f)
(a) Plane joint
(b)
(c)
(a)
(e)
(d)
© 2015 Pearson Education, Inc.
Figure 5.32b Types of synovial joints.
Humerus
Ulna
Nonaxial
Uniaxial
Biaxial
Multiaxial
(f)
(b)
(c)
(a)
(e)
(d)
© 2015 Pearson Education, Inc.
(b) Hinge
joint
Figure 5.32c Types of synovial joints.
Nonaxial
Uniaxial
Biaxial
Multiaxial
Ulna
Radius
(f)
(c) Pivot joint
(b)
(c)
(a)
(e)
(d)
© 2015 Pearson Education, Inc.
Figure 5.32d Types of synovial joints.
Nonaxial
Uniaxial
Biaxial
Multiaxial
(f)
(b)
(c)
(a)
(e)
(d)
© 2015 Pearson Education, Inc.
Metacarpal
Phalanx
(d) Condylar joint
Figure 5.32e Types of synovial joints.
Carpal
Metacarpal #1
Nonaxial
Uniaxial
Biaxial
Multiaxial
(f)
(e) Saddle joint
(b)
(c)
(a)
(e)
(d)
© 2015 Pearson Education, Inc.
Figure 5.32f Types of synovial joints.
Nonaxial
Uniaxial
Biaxial
Multiaxial
(f)
Head of
humerus
(b)
(c)
Scapula
(f) Ball-and-socket joint
(a)
(e)
(d)
© 2015 Pearson Education, Inc.
Inflammatory Conditions Associated
with Joints
 Bursitis—inflammation of a bursa, usually caused
by a blow or friction
 Tendonitis—inflammation of tendon sheaths
 Arthritis—inflammatory or degenerative diseases of
joints
 Over 100 different types
 The most widespread crippling disease in the United
States
 Initial symptoms: pain, stiffness, swelling of the joint
© 2015 Pearson Education, Inc.
Clinical Forms of Arthritis
 Osteoarthritis (OA)
 Most common chronic arthritis
 Probably related to normal aging processes
 Rheumatoid arthritis (RA)
 An autoimmune disease—the immune system
attacks the joints
 Symptoms begin with bilateral inflammation of
certain joints
 Often leads to deformities
© 2015 Pearson Education, Inc.
Figure 5.33 X-ray image of a hand deformed by rheumatoid arthritis.
© 2015 Pearson Education, Inc.
Clinical Forms of Arthritis
 Gouty arthritis (gout)
 Inflammation of joints is caused by a deposition of
uric acid crystals from the blood
 Can usually be controlled with diet
 More common in men
© 2015 Pearson Education, Inc.
Developmental Aspects of the Skeletal System
 Fontanels
 Allow brain growth and ease birth passage
 Present in the skull at birth
 Completely replaced with bone within 2 years after
birth
© 2015 Pearson Education, Inc.
Developmental Aspects of the Skeletal System
 Growth of cranium after birth is related to brain
growth
 Increase in size of the facial skeleton follows tooth
development and enlargement of the respiratory
passageways.
© 2015 Pearson Education, Inc.
Figure 5.34 Ossification centers in the skeleton of a 12-week-old fetus are indicated by the darker areas. Lighter regions are still fibrous or cartilaginous.
Frontal
bone
of skull
Mandible
Parietal
bone
Occipita
bone
Clavicle
Scapula
Radius
Ulna
Humerus
Femur
Tibia
Ribs
Vertebra
Hip bone
© 2015 Pearson Education, Inc.
Skeletal Changes Throughout Life
 Fetus
 Long bones are formed of hyaline cartilage
 Flat bones begin as fibrous membranes
 Flat and long bone models are converted to bone
 Birth
 Fontanels remain until around age 2
© 2015 Pearson Education, Inc.
Skeletal Changes Throughout Life
 Adolescence
 Epiphyseal plates become ossified, and long bone
growth ends
 Size of cranium in relationship to body
 2 years old—skull is larger in proportion to the body
compared to that of an adult
 8 or 9 years old—skull is near adult size and
proportion
 Between ages 6 and 11, the face grows out from the
skull
© 2015 Pearson Education, Inc.
Figure 5.35a Differences in the growth rates for some parts of the body compared to others determine body proportions.
Human newborn
(a)
© 2015 Pearson Education, Inc.
Human adult
Figure 5.35b Differences in the growth rates for some parts of the body compared to others determine body proportions.
Newborn
(b)
© 2015 Pearson Education, Inc.
2 yrs.
5 yrs.
15 yrs.
Adult
Skeletal Changes Throughout Life
 Curvatures of the spine
 Primary curvatures are present at birth and are
convex posteriorly
 Secondary curvatures are associated with a child’s
later development and are convex anteriorly
 Abnormal spinal curvatures (scoliosis and lordosis)
are often congenital
© 2015 Pearson Education, Inc.
Figure 5.18 Abnormal spinal curvatures.
(a) Scoliosis
© 2015 Pearson Education, Inc.
(b) Kyphosis
(c) Lordosis
Skeletal Changes Throughout Life
 Osteoporosis
 Bone-thinning disease afflicting
 50 percent of women over age 65
 20 percent of men over age 70
 Disease makes bones fragile, and bones can easily
fracture
 Vertebral collapse results in kyphosis (also known as
“dowager’s hump”)
 Estrogen aids in health and normal density of a
female skeleton
© 2015 Pearson Education, Inc.
Figure 5.36 Osteoporosis.
© 2015 Pearson Education, Inc.
Figure 5.37 Vertebral collapse due to osteoporosis.
Age 40
© 2015 Pearson Education, Inc.
Age 60
Age 70