Anatomy- Chp 7

appendicular skeleton

limbs + girdles that attach limbs to axial skeleton

functions of appendicular skeleton

• movement and mobility

• manipulation of environment

• weight bearing and locomotion

• protection of pelvic organs

components of appendicular skeleton

• pectoral girdle + upper limbs

• pelvic girdle + lower limbs

pectoral girdle and upper limb

• each upper limb + girdle = 32 bones

• primary function: position the hand for tasks

• pectoral girdle is highly mobile but less stable

bones of pectoral girdle

clavicle and scapula

clavicle

• S-shaped bones

• only direct bony connection between upper limb and axial skeleton

• articulates:

  • medially with manubrium (sternoclavicular joint)

  • laterally with acromion of scapula (acromioclavicular joint)

functions of clavicle

• transfers upper-limb weight to axial skeleton

• allows wide range of shoulder movement

key markings of clavicle

• conoid tubercle

• costal tuberosity

• common fracture sight

scapula

• flat, triangular bone on posterior thorax

• no direct attachment to ribs → mobility

key features of scapula

• glenoid cavity- articulates with humerus (shoulder joint)

• acromion- articulates with clavicle

• coracoid process- muscle attachment

• scapular spine

• supraspinous fossa

• infraspinous fossa

• subscapular fossa

• supraglenoid tubercle- biceps attachment

• infraglenoid tubercle- triceps attachment

humerus

articulates with scapula at shoulder

proximal features of scapula

• head

• anatomical neck

• greater tubercle

• lesser tubercle

shaft features of humerus

• deltoid tuberosity

• radial groove

distal features of humerus

• trochlear- ulna

• capitulum- radius

• medial and lateral epicondyles

• olecranon process

• coronoid fossa

ulna

• medial forearm

• olecranon

• coronoid process

radius

• lateral forearm

• rotates during pronation/supination

carpals- proximal row

lateral → medial; scaphoid, lunate, triquetrium, pisiform

carpals- distal row

lateral → medial; trapezium, trapezoid, capitate, hamate

wrist and hand

• carpals (8)

• metacarpals (5)

• phalanges (14)

  • fingers: 3 each

  • thumb: 2

pelvic girdle and lower limb

• pelvic girdle= weight-bearing, strong, stable

• transfers force from lower limbs to axial skeleton

• protects pelvic organs and fetus (in females)

• lower limb= 30 bones per side

pelvic girdle

• made of 2 hip (coxal) bones

• hip fusion complete by age 25

• sacroiliac joint, pubic symphysis

• acetabulum

• pelvis

• greater (false) pelvis, and lesser (true) pelvis

pelvis

hip bones + sacrum + coccyx

hip bone

formed by fusion of ilium, ischium, and pubis

upper limb bones

humerus, ulna, radius, carpals, metacarpals, phalanges

lower limb bones

femur, patella, tibia, fibula, tarsals, metatarsals, phalanges

femur

longest bone in body

proximal features of femur

• head

• neck

• greater trochanter

• lesser trochanter

distal femur features

medial and lateral condyles

patella

• sesamoid bone

• forms in quadriceps tendon

• improves leverage of knee extensors

tibia

• medial, weight-bearing

• tibial tuberosity

• anterior crest

• medial malleolus

fibula

• lateral, slender

• head

• lateral malleolus- ankle stability

tarsals

• talus- articulates with tibia and fibula

• calcaneus- heel, weight transfer

arches of foot phalanges

• longitudinal arch

• transverse arch

• help distribute body weight and absorb shock

skeleton can reveal..

in regards to variation; age, sex, genetic heritage, body size, muscle development, medical history

indicators of variation in skeletons

• pelvic shape

• skull features

• epiphyseal fusion

• bone density

• tooth condition

age changes of skeleton

begin in infancy, degenerative changes start at 30-40 years

developmental dysplasia of the hip (DDH)

malformed acetabulum due to poor femoral head positioning

female skeleton differences

in DDH; wider pelvis, greater knee valgus, increased ACL and stress fracture risk

prevention focus of DDH

strength, stability, balance, coordination

appendicular skeleton

• pectoral girdles- 4

• upper limbs- 60

• pelvic girdle- 2

• lower limbs- 60

pectoral girdles

• clavicle- 2

• scapula- 2

upper limbs

humerus- 2

radius- 2

ulna- 2

carpal bones- 16

metacarpals- 10

phalanges- 28

pelvic girdle

• hip bones- 2

lower limbs

• femur- 2

• patella- 2

• tibia- 2

• fibula- 2

• tarsal bones- 14

• metatarsals- 10

• phalanges- 28

sternoclavicular joint

only direct connection between pectoral girdle and axial skeleton

clavicle structures

• sternal end

• acromial end

• facet for articulation with acromion

• conoid tuberosity

• costal tuberosity

• sternal facet

scapula structures

• acromion

• lateral angle

• subscapular fossa

• lateral border

• body

• inferior angle

• superior angle

• superior border

• coracoid process

• supraglenoid tubercle

• glenoid cavity

• spine

• medial border

• supraspinous fossa

• neck

• infraspinous fossa

humerus structures

• greater tubercle

• lesser tubercle

• head

• anatomical neck

• inter-tubercular sulcus

• surgical neck

• deltoid tuberosity

• radial groove

• radial fossa

• lateral epicondyle

• capitulum

• trochlea

• coronoid fossa

• medial epicondyle

interosseous membrane

what holds radius and ulna together?

hands

• scaphoid

• lunate

• triquetrum

• pisiform

• trapezium

• trapezoid

• capitate

• hamate

• metacarpals

• proximal, middle, distal phalanges

coxal structures

• iliac crest

• intervertebral disc

• sacro-iliac joint

• ilium

• pubis

• ischium

• pubic symphysis

• iliac fossa

• sacrum

• arcuate line

• pectinil line

• superior pubic ramus

• acetabulum

• pubic tubercle

• pubic crest

• obturator foramen

• inferior pubic ramus

sacro-iliac joint

only direct connection between pelvic girdle and axial skeleton

adaptations for childbearing in female pelvis

• relatively broad, low pelvis

• ilia that project farther laterally

• less curvature on the sacrum and coccyx

• wider, more circular pelvic inlet

• enlarged pelvic outlet

• broader pubic angle

femur structures

• head

• neck

• lesser trochanter

• greater trochanter

• interochanteric line

• shaft

• patellar surface

• lateral epicondyle and condyle

• medial epicondyle and condyle

• gluteal tuberosity

• pectineal line

• linea aspera

• intertrochanteric crest

• intercondylar fossa

• popliteal surface

• adductor tubercle

• lateral and medial supracondylar ridge

interosseous mebrane

what holds tibia and fibula together?

feet

• calcaneus

• talus

• navicular

• cuboid

• lateral, intermediate, and medial cuneiform

• proximal, middle, distal phalanges