OSSIFICATION

· growing end usually

· appears earlier

· fuses later

clavicle

· forms in membrane

· at 5 wks

· first bone to form

· 2 secondary centres

· one at each end

· appear in teens and fuse in twenties

scapula

· forms in membrane

· at 6 wks

· bony centre at 8 wks

· 6 secondary centres appear at puberty and fuse at 25 yrs

· 2 in acromion

· 2 in coracoid

· 1 in vertebral border

· 1 in inferior angle

humerus

· centre in shaft at 8th wk

· proximal epiphyses

· head at 1 yr

· greater tuberosity at 3 yrs

· lesser tuberosity at 5 yrs

· fuse together at 7th yr

· fuse to shaft at 20 yrs

· distal epiphyses

· CRITOE

· fuse with shaft at 18 yrs

radius

· centre in shaft at 8th wk

· distal epiphysis

· appears at 2 yrs and fuses at 20 yrs

· proximal epiphysis

· appears at 4 yrs and fuses at 12 yrs

ulna

· centre in shaft at 8th wk

· distal head appears at 6 yrs and fuses at 20 yrs

· no proximal epiphysis except olecranon

· appears at 10 yrs and fuses at 18 yrs

hand

Carpus

· all cartilagenous at birth

· each from one centre

· appear at yearly intervals

· capitate at 1 yr

· hamate, triquetral, lunate, tripezium, scaphoid, trapezoid

· pisiform at 10 yrs

Long bones

· centre in shaft in utero

· secondary centre at age 2

· base of every bone except

· metacarpals of palm (MC II-V) where centre at head

· fuse at age 20

pelvis

· develops in cartilage

· three centres near acetabulum

· ilium in 2nd mth

· ischium in 3rd mth

· pubis in 4th mth

· ischial and pubic rami fuse at age 7

· Y-shaped cartilage in floor of acetabulum

· begins to fuse at 12 yrs

· several smaller centres (ossa acetabuli)

· complete fusion at 15 yrs

· strips of cartilage appear at 15 yrs

· iliac crest

· AIIS

· pubic symphysis

· ischial tuberosity

FEMUR

· centre in shaft at 8th wk

· proximal epiphyses

· head at 1 yr

· greater trochanter at 3 yrs

· lesser trochanter at 12 yrs

· all fuse at age 18

· distal epiphysis

· appears at birth and fuses at age 20

patella

· appears at 3 yrs

· may be more than one centre

tibia

· centre in shaft at 8th week

· proximal epiphysis

· appears just after birth and fuses at age 20

· tuberosity appears at puberty

· distal epiphysis

· appears age 1 yr and fuses at 18 yrs

fibula

· centre in shaft appears at 8th week

· head appears at 4 yrs and fuses at 20 yrs

· lower end appears at 2 yrs and fuses at 18 yrs

foot

· 3 tarsal bones ossified at birth

· calcaneus at 6th mth

· talus at 7th mth

· cuboid at 9th mth (medicolegal - maturity of foetus)

· navicular in 4th yr

· cuneiforms

· medial in 3rd yr

· intermediate in 4th yr

· lateral in 1st yr

· metatarsals and phalanges

· shafts ossify in utero

· epiphyseal centres appear in 5th yr and join in 18th yr

· epiphysis of 1st MT at base and lesser MTs at head

· calcaneal apophysis

· appears in 10th yr

· joins in 18th yr

ribs

· develop in membrane

· ossify from back forwards

· segment remains unossified (costal cartilage)

· secondary centres for head and tubercle

· appear age 15 yrs

· fuse age 25 yrs