Ages of ossification

Question 1

AGES of OSSIFICATION

Pelvis

Answer 1

Three centres of ossification

1: Ilium ~ 2 months fetal life
2: Ischium 3 months
3: Pubis at 4 months
4: Ischial and pubic rami 7 years
5: The ‘Y’ shaped cartilaginous physis of the three bones after puberty (15 years)

Question 2

AGES of OSSIFICATION

Femur

Answer 2

Greater trochanter 3 years
Lesser trochanter 12 years
All fuse with the shaft at about 18 years of age
Centre of the lower end unites with the shaft at about 20 years

Question 3

AGES of OSSIFICATION

Patella

Answer 3

Ossification is complete soon after puberty

Question 4

AGES of OSSIFICATION

Tibia

Answer 4

Upper epiphysis joins with the shaft at about 20 years

Secondary centre for the tuberosity about puberty

Distal epiphysis joins the shaft at about 18 years

Question 5

AGES of OSSIFICATION

Fibula

Answer 5

Proximal end fuses with the shaft at about 20 years

Distal end fuses with the shaft at about 18 years

Question 6

AGES of OSSIFICATION

Foot

Answer 6

Bones of the tarsus are ossified at birth calcaneus 6/12
Talus 7/12

Cuboid 9/12 intra-uterine life (ossification is medico-legal evidence of maturity)

Navicular 4th year

Cuneiforms:

• lateral 1st year
• medial 3rd year
• intermediate 4th years

Metatarsals - fuse at about 18 years (epiphysis of the 1st is at the base and at the head of the other toes)

Question 7

AGES of OSSIFICATION

Scapula

Answer 7

The centre at the base of the coracoid appears at about 10 years and fuses with the glenoid at
puberty

At birth the blade and spine are ossified

Question 8

Humerus

Answer 8

Upper end

1. Head in the 1st year
2. Greater tuberosity in the 3rd year
3. Lesser tuberosity in the 5th year
4. These fuse together by the 7th year and to the shaft at about 20 years

Lower end

1. Capitulum in the 2nd year (Radial head in the 4th year)
2. Medial epicondyle in the 5th year
3. Trochlea in the 12th year
4. Lateral epicondyle in the 13th year
5. Union with the shaft occurs at about 18 years

Question 9

Radius

Answer 9

Centre for the head appearing in the 4th year, which fuse with the shaft at about 18 years

Question 10

Ulna

Answer 10

The head ossifies at about 6 years and fuses with the shaft at about 20 years.

Question 11

Hand

Answer 11

Each carpal bone ossifies from one centre the largest (capitate in the first year and then one each year
until the 7th with the pisiform becoming ossified in the 10th year)

􀁸 Capitate: 1st year
􀁸 Hamate: 2nd year
􀁸 Triquetral: 3rd year
􀁸 Lunate: 4th year
􀁸 Trapezium: 5th year
􀁸 Scaphoid: 6th year
􀁸 Trapezoid: 7th year
􀁸 Pisiform: 10th year