Bones, Part 1: The Appendicular...

1

PowerPoint® Lecture Slides prepared by Leslie Hendon University of Alabama, Birmingham

C H A P T E R

Copyright © 2011 Pearson Education, Inc.

Part 1

8 Bones, Part 1: The Appendicular Skeleton


The Appendicular Skeleton

•  Pectoral girdle •  Attaches the upper limbs to the trunk

•  Pelvic girdle •  Attaches the lower limbs to the trunk

•  Upper and lower limbs differ in function •  Share the same structural plan


The Pectoral Girdle

•  Consists of the clavicle and the scapula •  Pectoral girdles do not quite encircle the

body completely •  Medial end of each clavicle articulates with

the manubrium and first rib •  Laterally—the ends of the clavicles join the

scapulae •  Scapulae do not join each other or the axial

skeleton


The Pectoral Girdle

•  Provides attachment for many muscles that move the upper limb

•  Girdle is very light and upper limbs are mobile •  Only clavicle articulates with the axial skeleton •  Socket of the shoulder joint (glenoid cavity) is

shallow • Good for flexibility, bad for stability


Clavicle Acromio- clavicular joint

Scapula

(a) Articulated pectoral girdle

Articulated Pectoral Girdle

Figure 8.1a

PLAY Shoulder


Clavicles

Figure 8.1b, c

Acromial (lateral) end (b) Right clavicle, superior view

Posterior

Sternal (medial) end

Anterior

Acromial end

Trapezoid line

Conoid tubercle

Anterior

Posterior

Sternal end

(c) Right clavicle, inferior view

Tuberosity for costoclavicular ligament

2


Scapulae

•  Lie on the dorsal surface of the rib cage •  Located between ribs 2–7 •  Have three borders •  Superior •  Medial (vertebral) •  Lateral (axillary)

•  Have three angles •  Lateral, superior, and inferior


Structures of the Scapula

Figure 8.2a

Acromion

Coracoid process

Suprascapular notch Superior border

Superior angle

Subscapular fossa

Medial border

Inferior angle

Glenoid cavity

Lateral border

(a) Right scapula, anterior aspect


Superior angle

Medial border

Coracoid process Suprascapular notch

Acromion

Glenoid cavity at lateral angle

Lateral border

Infraspinous fossa

Spine

(b) Right scapula, posterior aspect

Supraspinous fossa


Figure 8.2b Copyright © 2011 Pearson Education, Inc.


Figure 8.2c

Coracoid process Glenoid cavity

(c) Right scapula, lateral aspect

Infraglenoid tubercle

Supraglenoid tubercle

Supraspinous fossa

Subscapular fossa

Inferior angle

Acromion

Infraspinous fossa

Spine

Supraspinous fossa

Infraspinous fossa

Subscapular fossa

Posterior Anterior


The Upper Limb

•  30 bones form each upper limb •  Grouped into bones of the: •  Arm •  Forearm •  Hand


Arm

•  Region of the upper limb between the shoulder and elbow

•  Humerus •  The only bone of the arm •  Longest and strongest bone of the upper limb •  Articulates with the scapula at the shoulder •  Articulates with the radius and ulna at the

elbow

3


Structures of the Humerus of the Right Arm

Figure 8.3a, b

Greater tubercle

Lesser tubercle

Intertubercular sulcus

Lateral supracondylar ridge

Radial fossa

Capitulum

Head of humerus

Anatomical neck

Deltoid tuberosity

Coronoid fossa

Medial epicondyle

Trochlea (a) Anterior view

Head of humerus

Anatomical neck

Radial groove

Olecranon fossa

Medial epicondyle

Trochlea

Surgical neck

Deltoid tuberosity

Greater tubercle

Lateral epicondyle

Medial supracondylar ridge

(b) Posterior view


Structures of the Humerus of the Right Arm: the elbow

Figure 8.3c, d

Coronoid fossa

Radius

Radial tuberosity

Head of radius

Capitulum

Trochlea

(c) Anterior view at the elbow region

Humerus

Medial epicondyle

Coronoid process of ulna

Ulna Radial notch

Olecranon fossa

Ulna

Olecranon process

Medial epicondyle

(d) Posterior view of extended elbow

Humerus

Lateral epicondyle

Head

Radius

Neck


Forearm

•  Formed from the radius and ulna •  Proximal ends articulate with the humerus •  Distal ends articulate with carpals •  Radius and ulna articulate with each other at the

proximal and distal radioulnar joints •  The interosseous membrane

•  Interconnects radius and ulna •  In anatomical position; the radius is lateral and the ulna

is medial


Ulna and Radius

•  Ulna •  Main bone responsible for forming the elbow joint with the humerus •  Hinge joint allows forearm to bend on arm •  Distal end is separated from carpals by fibrocartilage •  Plays little to no role in hand movement

•  Radius •  Superior surface of the head of the radius articulates with the

capitulum •  Medially—the head of the radius articulates with the radial notch of the

ulna •  Contributes heavily to the wrist joint

•  Distal radius articulates with carpal bones •  When radius moves, the hand moves with it


Proximal Part of the Ulna

Figure 8.4a, b

Radial notch of the ulna

Olecranon process

Trochlear notch

Coronoid process Proximal radioulnar joint

Distal radioulnar joint

Ulnar notch of the radius Head of ulna

Styloid process of ulna

Interosseous membrane Ulna

Head Neck Radial tuberosity

Radius

Styloid process of radius

(a) Anterior view

Olecranon process

Styloid process of radius

Radius

Neck of radius

Head of radius

Ulnar notch of the radius

Head of ulna

Styloid process of ulna

Interosseous membrane Ulna

(b) Posterior view


Radius and Ulna

Figure 8.4c, 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

Head of ulna

Styloid process

Articulation for scaphoid

Articulation for lunate

Styloid process

View

4


Proximal Ends of the Radius and Ulna at the elbow

Figure 8.3c, d

Coronoid fossa

Radius

Radial tuberosity

Head of radius

Capitulum

Trochlea

(c) Anterior view at the elbow region

Humerus

Medial epicondyle

Coronoid process of ulna

Ulna Radial notch

Olecranon fossa

Ulna

Olecranon process

Medial epicondyle

(d) Posterior view of extended elbow

Humerus

Lateral epicondyle

Head

Radius

Neck


Hand

•  Includes the following bones •  Carpus—wrist •  Metacarpals—palm •  Phalanges—fingers


Carpus •  Forms the true wrist—the proximal region of the

hand •  Gliding movements occur between carpals •  Composed of eight marble-sized bones •  Carpal bones

•  Are arranged in two irregular rows •  Proximal row from lateral to medial

•  Scaphoid, lunate, triquetral, and pisiform •  Distal row from lateral to medial

•  Trapezium, trapezoid, capitate, and hamate •  A mnemonic to help remember carpals:

•  Sally left the party to take Carmen home


Bones of the Hand

Figure 8.6a, b

Trapezoid Trapezium

Scaphoid Triquetrum Lunate

Capitate Hamate

5 4 3 2 1 5 4 3 2 1

Phalanges

Metacarpals

Carpals Carpals

(a) Anterior view of right hand (b) Posterior view of right hand

Radius Ulna

Sesamoid bones Base

Shaft

Proximal Middle Distal

Head

Ulna

Triquetrum Lunate

Capitate Hamate

Pisiform

Carpals


•  Metacarpus •  Five metacarpals radiate distally from the wrist •  Metacarpals form the palm

•  Numbered 1–5, beginning with the pollex (thumb) •  Articulate proximally with the distal row of carpals •  Articulate distally with the proximal phalanges

•  Phalanges •  Numbered 1–5, beginning with the pollex (thumb) •  Except for the thumb, each finger has three phalanges

•  Proximal, middle, and distal

Copyright © 2011 Pearson Education, Inc. Figure 8.6b

5

Copyright © 2011 Pearson Education, Inc. Table 8.1


Pelvic Girdle

•  Attaches lower limbs to the spine •  Supports visceral organs •  Attaches to the axial skeleton by strong ligaments •  Acetabulum is a deep cup that holds the head of the

femur •  Lower limbs have less freedom of movement

•  Are more stable than the arm •  Consists of paired hip bones (coxal bones) •  Hip bones unite anteriorly with each other •  Articulates posteriorly with the sacrum


Bones of the Pelvic Girdle

Figure 8.8a

PLAY Pelvis

Coxal bone (os coxae or hip bone)

llium

Sacroiliac joint

Iliac fossa

Pubis

Ischium

Sacrum

Base of sacrum

Sacral promontory

Pelvic brim Acetabulum

Pubic crest Pubic symphysis

Iliac crest

Coccyx

Pubic arch

Anterior inferior iliac spine

Anterior superior iliac spine

Pubic tubercle

(a) Pelvic girdle


The Pelvic Girdle

•  Consists of three separate bones in childhood •  Ilium, ischium, and pubis

•  Bones fuse, retain separate names to regions of the coxal bones

•  Acetabulum •  A deep hemispherical socket on lateral pelvic surface


Ilium

•  Large, flaring bone •  Forms the superior region of the coxal bone •  Site of attachment for many muscles •  Articulation with the sacrum forms sacroiliac joint


Ischium •  Forms posteroinferior region of the coxal bone •  Anteriorly—joins the pubis •  Ischial tuberosities

•  Are the strongest part of the hip bone Pubis • Forms the anterior region of the coxal bone • Lies horizontally in anatomical position • Pubic symphysis

• The two pubic bones are joined by fibrocartilage at the midline

• Pubic arch—inferior to the pubic symphysis • Angle helps distinguish male from female pelves

6


Lateral and Medial Views of the Hip Bone

Figure 8.8b, c

Ilium Ischium Pubis

Ilium Ala

Tubercle of the iliac crest

Anterior gluteal line Posterior gluteal line

Posterior superior iIiac spine

Greater sciatic notch

Posterior inferior iliac spine

Ischial body

Ischial spine

Lesser sciatic notch

Ischial tuberosity

Ischium

Ischial ramus

Inferior gluteal line

Acetabulum

Pubic body

Iliac crest



Pubis

Inferior ramus of pubis

(b) Lateral view, right hip bone

Iliac fossa

Ilium

Iliac crest



Arcuate line

Pubic tubercle

Superior ramus of pubis

Inferior ramus of pubis

Posterior superior iliac spine

Obturator foramen

Body of the ilium

Ischium

Ischial ramus

(c) Medial view, right hip bone

Auricular surface

Ischial spine

Posterior inferior iliac spine

Articular surface of pubis (at pubic symphysis)


True and False Pelves

•  Bony pelvis is divided into two regions •  False (greater) pelvis—bounded by alae of

the iliac bones •  True (lesser) pelvis—inferior to pelvic brim • Forms a bowl containing the pelvic organs


True and False Pelves

Figure 8.9b

Anterior abdominal wall False pelvis

Pelvic brim, defining pelvic inlet True

pelvis

Coccyx

Plane of pelvic outlet

Symphyseal surface

(b) True and false pelves

Plane through midpelvis


Pelvic Structures and Childbearing

•  Major differences between male and female pelves •  Female pelvis is adapted for childbearing • Pelvis is lighter, wider, and shallower than

in the male • Provides more room in the true pelvis


Female and Male Pelves

Table 8.2 (1 of 2) Copyright © 2011 Pearson Education, Inc.

Female and Male Pelves

Table 8.2 (2 of 2)

7


The Lower Limb

•  Carries the entire weight of the erect body •  Bones of lower limb are thicker and stronger

than those of upper limb •  Divided into three segments •  Thigh, leg, and foot


Thigh

•  The region of the lower limb between the hip and the knee

•  Femur—the single bone of the thigh •  Longest and strongest bone of the body •  Ball-shaped head articulates with the

acetabulum


Neck Fovea capitis Greater

trochanter

Inter- trochanteric crest

Lateral condyle Lateral epicondyle

Head

Intertrochanteric line

Lesser trochanter

Gluteal tuberosity

Linea aspera

Intercondylar fossa

Medial and lateral supracondylar lines

Medial condyle

Medial epicondyle

Adductor tubercle

Anterior view Posterior view (b) Femur (thigh bone)

Lateral epicondyle

Patellar surface

Structures of the Femur

Figure 8.10b Copyright © 2011 Pearson Education, Inc.

Patella

•  Triangular sesamoid bone •  Imbedded in the tendon that secures the

quadriceps muscles •  Protects the knee anteriorly •  Improves leverage of the thigh muscles

across the knee


Leg •  Refers to the region of the lower limb between the knee and the ankle •  Composed of the tibia and fibula

•  Tibia—more massive medial bone of the leg •  Receives weight of the body from the femur

•  Fibula—stick-like lateral bone of the leg •  Interosseous membrane

•  Connects the tibia and fibula •  Tibia articulates with femur at superior end

•  Forms the knee joint •  Tibia articulates with talus at the inferior end

•  Forms the ankle joint •  Fibula does not contribute to the knee joint

•  Stabilizes the ankle joint


Structures of the Tibia and Fibula

Figure 8.11a, b

8


Structures of the Tibia and Fibula

Figure 8.11c–e

Lateral condyle Tibial tuberosity

(c) Anterior view, proximal tibia

Lateral condyle

Fibula articulates here

Line for soleus muscle

(d) Posterior view, proximal tibia

(e) Fracture of both malleoli

Fracture sites


The Foot •  Foot is composed of

•  Tarsus, metatarsus, and the phalanges •  Important functions

•  Supports body weight •  Acts as a lever to propel body forward when walking •  Segmentation makes foot pliable and adapted to

uneven ground


Tarsus •  Makes up the posterior half of the foot •  Contains seven bones called tarsals •  Body weight is primarily borne by the talus and calcaneus •  Trochlea of the talus

•  Site of articulation with the tibia •  Other tarsals are:

•  Cuboid and navicular •  Medial, intermediate, and lateral cuneiforms

Metatarsus • Consists of five small long bones called metatarsals • Numbered 1–5 beginning with the hallux (great toe) • First metatarsal supports body weight


Phalanges of the Toes

•  14 phalanges of the toes •  Smaller and less nimble than those of the fingers •  Structure and arrangement are similar to phalanges of

fingers •  Except for the great toe, each toe has three

phalanges •  Proximal, middle, and distal


Medial cuneiform

Phalanges

Metatarsals

Tarsals

Navicular

Intermediate cuneiform

Talus

Calcaneus

(a) Superior view

Cuboid

Lateral cuneiform

Proximal Middle Distal

Trochlea of talus

5 4 3 2 1

Bones of the Foot

Figure 8.12a Copyright © 2011 Pearson Education, Inc.

Bones of the Foot

Figure 8.12b

Facet for medial malleolus

Calcaneal tuberosity (b) Medial view


Sustentaculum tali (talar shelf) Talus

Navicular

First metatarsal

Medial cuneiform

Calcaneus

9


Bones of the Foot

Figure 8.12c

PLAY Bones of the Foot

(c) Lateral view


Lateral cuneiform

Fifth metatarsal

Facet for lateral malleolus

Talus

Navicular

Cuboid Calcaneus


Arches of the Foot

•  Foot has three important arches •  Medial and lateral longitudinal arch •  Transverse arch


Medial longitudinal arch

Transverse arch

Lateral longitudinal arch

(a) Lateral aspect of right foot

Arches of the Foot

Figure 8.13a Copyright © 2011 Pearson Education, Inc.

Arches of the Foot

Figure 8.13b


Lower Limb and Pelvis

Table 8.3 Copyright © 2011 Pearson Education, Inc.

Disorders of the Appendicular Skeleton

•  Bone fractures •  Hip dysplasia •  Head of the femur slips out of acetabulum

•  Clubfoot •  Soles of the feet turn medially

10


The Appendicular Skeleton Throughout Life

•  Growth of the appendicular skeleton •  Increases height •  Changes body proportions

•  Upper/lower body ratio changes with age •  At birth, head and trunk are 1.5 times as long

as lower limbs •  Lower limbs grow faster than the trunk •  Upper/lower body ratio of 1 to 1 by age 10


Changes in Body Proportions

Figure 8.15


The Appendicular Skeleton Throughout Life

•  Few changes occur in adult skeleton until middle age, when •  Skeleton loses mass •  Osteoporosis and limb fractures become more

common

Bones, Part 1: The Appendicular...

Documents

Transcript of Bones, Part 1: The Appendicular...